Well, not necessarily wet, as with gasoline. Not sure.

I did check (and recheck) the sensor gap. About 0.013, which is within spec.

The Wintec allows me to look at the voltages from the TPS, MAP, and MAT in real time (also "engine temp," which means water in those cars. I don't use this, as oil is too slow to warm, and CHT I am told is too fast for what basically is a warmup circuit). Nothing special there, other than that they are working, and I have given the TEC reasonable values for them. I can look at injector on and off time. It dithers around some, which might mean something.

I can add a WEGO - have a bung on each side for a separate O2 device, but haven't hooked that up, because I can't see what that will tell me, other than that left side is AF something, and I assume right side will be different with a hole not firing. Maybe if leaner, would mean no gas, and richer, no spark? But what does raw gas do to the O2 reading?

The Tec3r will act as a WEGO monitor, and for street use you can even have the sensor adjust things automatically. Not a good idea for a race motor, I am told. In many ways, tuning race motors for EFI is a lot simpler, as you only really care about WOT, and don't have to adjust cell by cell.

Plus I'm PB Blasting the right side bung plug so I can get it out.

I've thought of a scope. I have an ancient rack mount one stored away. Large and heavy. And I've never used it for automotive stuff. What would I be sensing? Where would I hook it up? What would I be looking for? Inductive clamp for each spark wire? I'm thinking those old nice six or eight traces displayed were for the coil wire on a distributor system? Or did they have six or eight clamps and inputs and were separate channels?

The effect of a no spark, fuel present condition is actually lean on the wideband. Seems backwards when you first think about it.

While WOT is important for race, you can also tune part throttle to keep things running clean and not fouling while also taking out much of the cold blooded nature of the engine. May systems will incorporate an RPM/TPS cutoff where lambda compensation is deactivated to allow for safe WOT/heavy load operation. Many of these systems do not recognize specific cylinder misfire so if a hole loses spark the ecu trims all 6 to compensate. You then end up with a rough running pig rich 5cyl.

Good morning Walt,
I think a scope would be useful in determining the relationship of the injector firing and the plug firing. If your scope is dual trace, which most are, you can put one probe on the DC voltage firing the injector coil and the other probe clamped on #5 ignition lead. If your ignition probe is a high tension lead you could actually read the amount of voltage firing the plug. A clamp type probe will only show you a spike of unknown voltage, but that is still useful. The scope will give you a time relationship of the events to one another.

Does the engine run like a six cylinder with one dead cylinder or is it running just barely, sometimes sounding like a 3 cylinder, then a 5, then a 6, then ........?

When you had the timing light clamped on the ignition lead, you mentioned the light was dancing around somewhat. Do you think it was #5 erratically firing at those times?

IMHO, I really think your engine is mechanically fine, but there's a wiring/electronic gremlin in the Tec3r. Have you spoke to Richard Clewett on this matter? He is an absolute wizard on these systems.

Other than a scope, and talking with Richard Clewett, I am rapidly running out of ideas.

It mostly runs like a 5 cylinder. I can try to persuade myself that the #2, while clearly firing, maybe isn't running as well as 1,3,4 and 6. But that's based on IR gun on exhaust sometimes showing the temp a bit lower than the other four. However, because there is a hose clamp around the header about an inch below the flange at the port (holds the EGT probe in), the insulating effect of that clamp could account for this. The greatly reduced temps on #5, which also has a hose clamp and EGT probe, really tell the tale. Plus the plugs - all but #5 are, if anything, a bit sooty rich (not so much so that the tailpipes (stingers, really) for either side are sooty). All #5 shows is a slight film of oil, which seems reasonable to me given that the cylinder is pumping but not firing to burn any of that off, and not enough to prevent sparking.

Jon at Electromotive couldn't think of anything having to do with the TEC3r system itself which would cause one cylinder out of six not to fire.

James Bricken recounted a situation he encountered where there was just enough amperage or voltage or general oomph for one injector of a paired set to fire, but not the other. Simple to test: pull the plug on the good injector and see if the recalcitrant one fires. I did this. Engine slowed down to act like a 4 cylinder engine.

In case there was some hidden defect in the wiring, I pulled all the injector plugs off, but a lot of tie wraps, and put the right bank plugs on the left bank injectors, and vice versa.

Guess what - aaaargh, #5 still dead.

I'm toying with putting carbs back on to see if there is some hidden mechanical issue no one has put a finger on.

If it's still waking up with carb clean/brake clean into the throat them it's certainly fuel related. I would replace that fuel injector (carry a spare or two for a race car isn't a terrible idea anyway). Make sure the injectors all match part#. Are they high impedance or low? Was the set purchased together? If low, does tec3 require resistor installation in the harness?

There are collector screens in the top of injectors where the fuel enters that may collect debris that makes it through the filter. Invert it, tap it out and check for debris. Could be blocking fuel flow.

Cycle the pump with the feed line off then injector and confirm the flow in that line is clear.


Issue is here somewhere, you'll find it.

Hi Walt,
Could you tell us a little about the crankshaft differences between the 2.8 LS and the 2.8 SS?

Have you clamped the timing light on cylinder #1 and get an idea what your initial timing is at idle?

If you're thinking of putting the carbs back on........
You could also swap ITB banks and see if the problem migrates over to Cylinder #2.

Walt,

This thread was brought to my attention. Check your ECU connector and verify that all the terminals are making a good connection. This is under TEC Tips on our web site.

Inconsistent sensor values can be caused by poor terminal connections. We have seen instances where the terminals in the gray and white connectors have been spread open, causing a poor connection to the ECU. Carefully check each terminal with a .040 diameter pin. When the pin is carefully inserted into the terminal, there must be tension on the pin. If there is no tension, carefully remove the red terminal lock on the ECU connector. This procedure is in the TEC3r manual. With the terminal lock removed, all the terminals are in clear view. Each terminal has 3 fingers that make contact with the ECU connector terminals. With a pointed object, carefully push each of the 3 fingers to the center of all the terminals. Replace the red terminal lock, making certain that each terminal is fully seated in the connector. Verify that each terminal has tension on a .040 diameter pin. Don't neglect to visually check each sensor and injector terminals as well. We have seen a number of the sensor terminals which have been damaged, causing false readings.

It says for inconsistent sensor readings but also applies to outputs such as coils and injectors.

Regards,

Richard

A 2.8 LS is 92x70.4 (Porsche's 2.8 RSR's dimensions). A SS is 95x66 - about one cc larger.

Using a timing light on a waste spark motor is a bit tricky, as you get one per rev. And my crank pulley doesn't have any convenient marks at around 14 degrees advance. I have tried different advance settings in the programming, and they do move the idle RPM around some, but have no effect on the problem child.

I've swapped connectors bank to bank. Swapping the ITB units is problematic, as they would swap ends, so the linkage wouldn't fit. I could probably figure out how to get the MAT and TPS sensor leads lengthened.

Compared to carburetors, the ITBs are (or seem to be) so simple that it is hard to see what could go wrong. There are only two internal passages - the idle air bleed, and the vacuum drilling. These are older model ITBs, with a single throttle shaft on each bank, so the butterflies all have to (and do) open together.

Richard - thank you for the suggestion. I had read (reread, actually) the tips from your helpful website to see if something suggested itself. Until I started to troubleshoot this problem, the white connector had been in place and untouched for three years now (gray one too, for that matter). I did pull the white connector to do continuity checks on the injector ground wiring, and later futzing with firmware. The fundamental theoretical problem is why the same injector driver pin which serves two injectors would only work for one. Especially since that injector has been swapped around with no change.

I'm going to pull the fuel rails and all the injectors, and inspect all the passages, and swap injectors bank for bank. I can't imagine finding a dead fly larva blocking #5 somewhere where swapping 4 and 5 previously wouldn't have revealed or dislodged, but there has to be something.

Walt,
You are correct with phased sequential or batch fire and swapping wires from side to side both ignition and fuel, would have exposed an electrical problem. Have you tried replacing the plugs. If it is specific to #5 there will be something, plugs, fuel or compression. One thing I've learned well over the years is to assume nothing. It's the simple things that will get you.

Richard

Walt & Richard,
According to Walt's info above, are the Clewett 60-1 pulley's interchangeable? Do different vintage cranks have different pulley key offsets?

The only thing left to do is ohm-out every pin on the connectors as Richard suggested. Makes sense; both engines were running before the Tec3r components were removed from one and applied to the other.
I may eat these words, but IT IS NOT A MECHANICAL PROBLEM. Not unless you stuffed a rag down #5's ports to protect the mechanicals. SmileWavy

A good contact cleaner might help with electrical faults.
I use Stablilant 22 on all connections (learned in the military).
It is mandatory on all connectors on aircraft....you can't afford to have an intermittant while in combat!
Bob

Richard - I replaced the plugs on the right side early on. No joy. Today I pulled the right side injectors and inspected the fuel rail. Clean as a whistle, though I ran a bristle brush through it anyway. No hard shell beetle stuck in the center hole or the like. Now the #6 injector is in the #5position when I get around to starting it again.

I don't know how to get at the filter on the injectors, nor do I have a test rig (other than the ITBs and fuel rails themselves) to check things. Doesn't look like I can easily backflush (standard Bosch pintle injectors), but I squirted brake cleaner into the inlet end, and let it flush back out just in case and because I had them out.

I discovered that the brown color of the body of these Bosch injectors is paint, and a paint my carb cleaner dissolved. But one mottled appearing injector isn't going to hurt. I sprayed their male connector prongs with a contact cleaner. Since I have the former left side (aka the working side) connectors on the right side now, I'm not sure what good spraying the female parts on the plugs is going to do, but I can try that too.

Next is pulling the right lower valve cover to see if anything is amiss in there, and to check exhaust valve spring pressures (no high hopes for any of this, given how much of it I was able to check through the intake valve cover side, though).

In addition to the "why does one side work but not the other of paired functions" conundrum, I have checked the resistance of the plug wires involved, and of the injector wires, including back to the ECU connector output pin. Nothing amiss that I could tell with my ohm meter.

But ultimately something simple is going to have to come out of hiding.

Still no joy
 

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Well, nothing amiss to be seen under the lower valve cover. That's an official Wil Ferch valve spring qualitative tester. #5 and #4 exhausts both equally stiff to the push, as one would expect. There is a bit of excess copper anti-seize on the headbolt by the #5 lower spark plug, but that's not unusual. You can see why it would be very hard for me to get the plug wires on the wrong plugs.

Any chance to start since moving the injector? I have my eye on that guy.

The cursed #5 cylinder
 

Lapkritis,
I think Walt already tried that.


Walt,
I just got over the very same problem with the turbo. There was a serious misfire/no fire on one the the cylinders. I immediately went to the plugs to check they were all properly snapped on the plug terminals. Got to #5 topside and found the plug connector loose on the plug. Tried to snap it back on to no avail. Pulled the plug off the Electromotive to inspect, nothing obvious. Pulled the plug out and found the terminal of the plug had snapped off! The rest of the plug was pulled out of the plug wire connector. I had found something wrong, but not what was causing my misfire. It's a twin-plug, so even if 5A does not fire, 5B does.
The plug 5A looked pretty fouled, so I decided to pull all the plugs. Everyone of them was carbon-fouled, badly. It must have been bad gas when I filled the tank last November and treated it with Sta-Bil. Winterized in this manner for the last 15 years and never gotten bit by it. Well, 12 new plugs and a bottle of Techron later, everything is back to normal.

Wish I could come up with something that would get you out of the dilemma your in Walt. Trying to think of something in the Tec3r that would pertain only to cylinder #5. Have you clamped on the timing light to plug wire 5A and then 5B with engine running to see if they are getting high voltage to fire the plugs?
Got get this narrowed down between fuel and ignition somehow. Hang in there. SmileWavy

I did clamp the timing light on 5A and B, and it flashed the same on them as it did on the numerous other wires I clamped it on. Because it is not a dialback, I can't really tell how spot on the firing is, or compare it with any other cylinders in terms of timing.

I suppose #2 injector electrical connector could not be swapped for #5 and vice versa?

That fact you're getting ignition to #5 kind of rules out ignition. Even if it were off, timing-wise, you would probably get some sort of backfire up thru the throttle body.

Could it be a broken lead/bad crimp on the injector or the ECU?

The brake clean response has me thinking either injector or driver.

Andrew...if you are thinking that the brake clean adds combustibles to the chamber to get the correct fuel/air ratio...I agree.
Walt...I know this is left field...is it possible that the feed to #5 injector is somehow partially plugged?
Perhaps the joint in the fuel rail is restricting the flow to that one injector.
If it's a "T" junction...maybe the tail of the "T" has slipped too far into the main rail.
Bob

What is the leakdown on #5?

How are you doing on this Walt?

Yes, I'm curious too.

Hope you and your family are doing ok and the Colorado fires are no where near you.

I've been off in Michigan at Parade, then visiting family along the way home.

Leakdown on #4 was 4%, and on #5 3.75%, all in both cases through the rings. Don't place much reliance on those absolute leakdown numbers - the two gauges don't quite zero the same to start with, etc. But nothing obvious there.

To add another test to the injector wiring, I swapped the right side wiring and plugs to the left side and vice versa. No joy.

Since the #5 is the middle injector, the end fittings on the fuel rail can't affect it in any obvious mechanical way. I pulled the rail and end fittings for inspection and a bristle brush, though there was nothing in there for it to brush. Each fuel rail is fed from its front end, and at its rear end each goes over to the fuel pressure regulator and return line. If this were an entirely new setup, especially if the fuel rails were at all asymmetric side to side, I'd wonder if there is some kind of standing wave action going on, but neither are the case and I don't think anything like that could happen anyway.

I've been thinking about what is different here, other than the fact that I rebuilt the motor without making any changes to its features.

One thing which is different is that the ITBs were attached to the motor which blew up the #6 piston. This sent oil and aluminum bits all over, including up the intake, out the intake stack into the air filter, and some aluminum and oil from all this made its way into the #5. This meant the #5 as well as the #6 ITB were a bit oily. So I'm going to swab the #5 (though I think I did this before reattaching the ITBs, and besides it didn't affect the #6). There really isn't any where in the ITB for debris to hide, much less cause trouble with lighting the fire.

We'll see if this, plus swapping yet another injector into #5 position, do any good.

I did not have time to read the whole thread so perhaps this has already been stated...

This is cable leading to #6. Assumption is it chaffed on the air filter box above it. This cut fuel off to 6. #5 is in same area so same could happen.

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Karl - thank you for pondering my plight.

I think your picture shows the cabling for the injectors on a 3.2 stock motor? I have aftermarket EFI on a race motor, with very little stock about it.

As it happens, I have checked (and rechecked) the injector wiring, and even swapped it side for side, and the wiring is good. And when tested the injector in the #5 position squirts fuel.

Which is what makes this so frustrating.

Swapping around injectors yet another time made no difference.

Yesterday I repeated, at greater length, the effect of squirting brake cleaner into the #5 intake. It caused that cylinder to fire for a while - doing it enough caused the EGT for that cylinder to rise to where it should be compared with the one for #2. But the effect of this wears off quickly, and firing stops.

I had pondered whether it was possible for a head to lack a battery ground connection. In addition to the many physical reasons why grounding the case must ground the heads, this pretty much proves that the plugs are firing.

I pulled the ITBs off the manifold, and squirted each injector on the right side into a pan. I didn't have something really suitable for gathering the squirted gasoline and measuring it, but it looked like all sprayed a roughly identical amount, as they should. I could see the gasoline spray out of #5. At cranking speed not much fuel is sprayed anyway, but it is there.

I also squirted carb cleaner through the only relevant orifice on the #5 ITB - the idle air bleed passage. It wasn't blocked (didn't think even if it was that would matter, but grasping at straws).

I rechecked the compression on #5. Previously, with a friend's tester, got 130 psi. With mine, and the engine pretty warm and the butterflies all propped wide open on that side, got 145 psi. I don't think that is high enough to prevent the plugs from sparking, or otherwise affect combustion.

With the engine idling nicely on five cylinders, I pulled each injector plug in sequence. For each cylinder except #5, the engine slowed a bit and ran a bit less smoothly (as one would expect).

So still no closer to figuring this out than before.

Got spark, got fuel, injectors fire, nothing wrong with plugs or wires. Hard to find it is something in the ECU or programming, because that is hard wired to ground (which energizes the injectors, which have 12V positive applied to them all the time when the ECU has power) the 2 and 5 with a single grounding transistor or other electronic switch. If wiring was bad, switching the 2 and 5 injector leads would have moved the problem, but it didn't. If the ECU or software had a problem, both 2 and 5 should have the same problem with fuel getting in to be lit off by the spark. But they don't.

Sending the ECU off to Electromotive for testing seems in the cards even if the most likely result of that is a statement that it is working fine.

At that point, I'll have to try the "back to carbs" approach to see if something mechanical neither I nor anyone else has suspected is causing this problem.

Walt, the injector must be dropping out once the engine is no longer cranking. The carb or brake cleaner is simply supplementing the fuel supply missing from the injector. Is there a two step limiter setting that was accidentally enabled? I've seen that before...

Idea way out in left field...
Is it possible that one of the cam lobes for #5 (probably the intake) is damaged?
Along that same line...what if the valve were sticking...not likely seeing the compression is good.
But if the lobe were worn...you could have this effect.
The reason I ask...I had a cam tear off a lobe in less than 10 minutes of running time once...it "doorknobbed" very nicely.
Bob

If it runs close to normal while you are spraying brake cleaner into it then ignition and compression are fine. Somehow that cylinder isn't getting fuel.

Pete

Fuel certainly seems at the heart of it.

I've looked at those cam lobes. Intake moves the rocker up and down like it should. Ditto exhaust.

I'll check my rev limiter settings, as there are several options. And to make sure I'm not on some kind of staged (one squirting for low RPM, and another chiming in for higher RPM) setting. However, with the injectors twined - each fires once per revolution, I'd need to be on a sequential injection setting to have one thing happen with 2, and another with 5. There is provision for individual cylinder trims, but that's only for sequential injection, which calls for a cam sensor, and I don't have one or use those features, so I don't know how it would know how to deal with just one cylinder. Plus for sequential you have to wire up the injectors differently, using three extra outputs (which are currently unused) from the ECU.

Keep those notions coming. Getting a cylinder to fire has been around for 120 or so years.

Walt...are these the same cams as before rebuild?
Also...#5 is the last cylinder to fire...is there some reason that the charge might dissipate before the plug gets around to sparking?
If the injectors all squirt at the beginning of the cycle (#1) then #5 might have less of a charge by the time the plug fires.
I remember trying to tune the Can-Am engines way back...and the stack lengths were a nightmare to get right...had everything to do with
charge "float" in the stacks...if you got them wrong...one or more cylinders would run lean.
Grasping at straws here.
Bob

How is the fuel pressure?

Intriguing. While there are many on here with more knowledge than me I was wondering if this may be a bad injector only when hot, kinda like starter heat soak. It is a coil actuated device, and resistance increases with heat...

I believe Walt has swapped the #2 with #5 to eliminate that.
Bob

what about borrowing a set of carbs?

Forgive the questions if they are not helpful, I don't have much experience with electronic injectors. How does the injector get it's ground? I know you checked the cylinder ground for the spark but what about the injector ground. Does it have a wire or ground to the rail? Maybe it loses it's ground when the engine is running somehow.

-Andy

They all get constant 12v from the key on circuit and the ecu switches the ground on and off to open the injector.

Same cams. This was a quickie rebuild - bearings, valve job, reset spring heights due to valve job (actually, I didn't measure spring heights on teardown), new cylinder base washers just because old ones looked a bit too crushed for my taste, and put back together.

I rerouted the right side injector wiring farther away from the plug wires, but that didn't help. I used actual starting fluid (ether?) when running it. Squirting it into the working intakes caused the idling ending to slow a bit! But into #5, same old thing - engine picked up, EGT picked up, my hand behind the exhaust felt more even pulses. Then back to no fire in #5. The #5 exhaust runner was hotter the farther away from the port it got! That has to be due to it getting next to the other runners, and picking up heat from them.

#5 has failed to fire when it had the #5, the #4, and the #6 injector in it. And #4 and 6 have worked fine no matter which injector is installed.

Redid leakdowns and compressions on the right bank. All were very close to each other. And I keep checking exhaust runner temperatures on the left bank, especially #2, just to confirm that that side is working right.

I have a set of Weber 46s. I can plug those in while the ECU is off to Electromotive for them to see if the ground which serves both 2 and 5 can somehow make 5 go bad without affecting 2.

But first I'm going to see if I can run alternate wires from the ECU injector output for 2/5 to the #5 injector without cutting any wires. And from the common positive to #5. Since swapping the loom didn't change anything, I don't hold out much hope.

Walt,

Are you sure the #5 injector is firing? You can use a noid light to test. Or if your ecu has the ablility (may good ones do) to see if the injector fires? You should hear it, or hear a change if you pull the connector during the test. Or use a stethescope. You can even use a 9v battery and a spare injector connector to test the actual injector while still connected to your fuel supply.

If it is gettig fuel and not firing you should see a pretty wet plug. If you pull a plug after running it and it is dry, then you are not getting fuel. With a stethescope and the motor running you should be able to tell if the injector is firing. If it is, pull it and run the engine with that injector spraying (or not) into a cup. I would not waste time putting carbs on as a test. Have you tried plugging the injector connector for the other cylinder that fires at the same time a #5 onto the #5 injector to see if the problem switches banks??

This should be straight forward if the injector is known to be good.

If you are sure you have spark (at the correct time) and have compression that really only leaves fuel......

I suspect that wiring or ECU is to blame assuming your injector and fuel supply is good....

Walt...my reasoning...
You have swapped the injector and found out in is NOT the injector itself.
You have swapped #2 with #5 wiring...same result...no change.
To my brain...that just leaves fuel delivery to the injector....or...something in the cylinder itself.
You have checked cam action...compression...and numbers look OK.
It has to be the fuel to the injector....is it possible to rig a different fuel manifold (temporary) ?
If you eliminate all the possibles...the last (and probably crazy one) is going to be the problem.
Bob

I couldn't figure out how you get a post to appear in italics, so I'll wing it. Jeff Alton asks:

*Are you sure the #5 injector is firing? You can use a noid light to test. Or if your ecu has the ablility (may good ones do) to see if the injector fires? You should hear it, or hear a change if you pull the connector during the test. Or use a stethoscope. You can even use a 9v battery and a spare injector connector to test the actual injector while still connected to your fuel supply.

--USED A NOID - bought a 12V led, which I believe is all NOID is? Flashed. First time I had the issue I used the stethoscope (actually, borrowed a friend's piece of small tubing, as I was at his house trying to get it going out in the country) to listen to all injectors. All clicked. Pulling the #5 connector makes no change in engine running. I have a spare connector, but why wouldn't I just use 12V? However, this sounds good and I'll do it. Timing of the injection pulses (one of which comes 180 cam degrees out of phase with the other anyway) shouldn't be critical, at least at idle. No worse than me spraying starter fluid in.

*If it is getting fuel and not firing you should see a pretty wet plug. If you pull a plug after running it and it is dry, then you are not getting fuel. With a stethoscope and the motor running you should be able to tell if the injector is firing. If it is, pull it and run the engine with that injector spraying (or not) into a cup. I would not waste time putting carbs on as a test. Have you tried plugging the injector connector for the other cylinder that fires at the same time a #5 onto the #5 injector to see if the problem switches banks??

--PLUG IS DRY. I can't pull injector and make it spray, as it requires the fuel rail, and something to hold it in the rail. However, I have opened the butterflies and spun the motor with no ignition - injector seems to spray. All three I have tried, which work on the other cylinders. I had carefully checked the wiring for continuity, and finally swapped the looms over from one side to the other - just called for snipping a few zip ties. Made zero difference! To deal with the need for fuel rail to test injectors, I just removed the entire throttle body assembly from the manifolds, and had them squirt into pans. Seemed about equal.

*This should be straight forward if the injector is known to be good.

--AGREED, but it doesn't seem to be.

*If you are sure you have spark (at the correct time) and have compression that really only leaves fuel......

--AGREED, but spark for #2 is spark for #5 in a waste spark DFU. 2 works, so timing for 5 must be OK. I've swapped terminals, and tried other plug wires without success. And putting a timing light clamp on the #5 wires shows flashes when engine running (on the other 5), just as it does for the other holes. Plus the fact that the hole fires when I spray a combustible fluid in says spark is at least sparking.

*I suspect that wiring or ECU is to blame assuming your injector and fuel supply is good....

--REASONABLE SUSPICIONS, but why would the ECU fire (by grounding) the #2 but not the #5, which uses the same ground - separate supply wires from a panel external to the ECU to each injector, but the ground wires are connected for each pair - come together in the middle - and a single wire goes to the ECU, which dictates when and for how long it is grounded. If one of the two wires from the injector plug were bad, swapping sides should have made a difference. But it doesn't. James Bricken suggested I pull the 2 to see if the 5 would then fire (he'd run across something like that), but that didn't work either. Which is why I am thinking of carbs.