I need help bad! 3.3 won't run at all.
 

I have a 1972 RS clone that I just replaced a 1986 Carrera engine with a 1987 3.3 Turbo engine. I was told that the 3.3 ran fine when removed. The engine had been sitting for quite some time before I got it so I did a leakdown and compression test on it. The numbers came back fine.

Dilemma: I am able to force the engine to run, but can’t get it to run on its own. If I press down slightly on the air flow sensor plate and open it up about 1/8 inch, the engine will start and idle fine as long as I keep the plate slightly opened. I have the fuel pump wired through a relay triggered directly off the ignition switch, so it is not affected by sensor plate position. The idle is at around 1500 rpm, dependent on how far I hold down the plate.

If I apply throttle, I have to manually open the sensor plate wider to keep up with the air intake. The engine will not move the sensor plate with its vacuum. The sensor plate is not bound up at all. It moves quite freely. It is tougher to move it when the fuel pressure is applied. The engine will rev to redline if I apply correct amounts of throttle and fuel “by hand”.

The vacuum that should open the sensor plate is virtually nonexistent. I went through the entire intake system to find vacuum leaks, and addressed them, but I still am losing all vacuum. I spray starting fluid at all of the potential leak prone areas, and there are no more apparent leaks.

I have the AAV bypassed and plugged at both ends.

I am of the opinion that I am still bringing in unmetered air from somewhere, but can’t for the life of me figure out where else it could be coming from.

Any ideas on where else to look? I’m pulling my hair out here!

Drew
wolf300tt at hotmail dot com
http://forums.pelicanparts.com/uploa...1270833191.jpg

Sounds like you Control Pressure is too high... It should be around 2 BAR when cold and 3.5 BAR when warm. It's controlled by the WUR.

If you have a CIS pressure gauge set, you need to verify your fuel pressures.

Remember, that the system pressure should be about 6-6.5 BAR [if you have 2 pumps].

** What's holding that "see-saw" down is the Control Pressure [CP]. On one side, you have vacuum pulling it down and on the other side is the CP pushing against the vacuum. It the CP is too high, then the vacuum will not be enough to pull the metering plate down.

Good luck...

I would agree with Mooney's input. But with your comment about engine vacuum being virtually nonexistant (is this presumption, or can you not feel any air being drawn down through the metering plate?). If no air, then read on:

The metering plate is the first place the intake air passes through, so it must deflect the plate unless the plate is stuck (which you say is not the case) or system fuel pressure is way too high.

Here are some exploratory questions that may seem condensending, but we need to know for sure (in answering, it's ok to say "well....DUH!!):
- Do you have a turbocharger hooked up (and all associated plumbing)? All the way from the rubber elbow connected to the metering plate housing, which in turn connects to the boost recirculation manifold "T" coupler, then on to the pipe and rubber couplers leading down to the turbo intake. The engine vacuum uses the turo and plumbing as the pathway to the metering plate housing.
- You do have the intercooler attached? If not, then all the air will be drawn directly through the throttle body instead of through the metering plate.
- Are both end caps present on the boost recirculation valve (the piston valve), and is the large (1/2" or so diam.) vacuum hose that attaches to the top cap of the recirc. valve hooked up? It's other end goes straight to the intake manifold post-throttle body, and if it was off you would suck all your needed engine air through that hole instead of across the metering plate.

You've gotta be sucking huge air somewhere. If that's not it, then it has to be your metering plate is not moving as freely as stated. Hang in there, the solution is just around the corner!

If the engine has been sitting for "quite some time" the CIS and WUR are probably all gummed up. With the engine off does the metering plate hang down in the bowl and move freely, is the fuel regulator gummed up, is the control plunger stuck in place?

Cole

Hope you get it worked out soon. Beautiful car BTW!

I like a long-hood turbo outlaw...that's sweet.

Your unmetered air hunch could very well be correct. What year 930 engine are you dealing with here? I'm not familiar with the later models, but earlier models like '78-'79 had an EGR system that plumbed directly into the manifold way in the back behind everything and sort of underneath the CIS airflow meter housing. Often times the EGR system is removed and the hole in the manifold is "plugged" with something. A shop did this to my car, and their crappy plug job failed and my car would not run at all due to the massive intake leak. By massive, were talking a hole about the size of a dime in the manifold. Like you, I could make the car run by manipulating that metering plate by hand. This spot is hard to inspect with the engine in the car but with mirrors and groping around its possible to check. Its a less obvious spot where you may have an intake leak.

Best picture I have of where this spot is (see circled area):

http://forums.pelicanparts.com/uploa...1270842290.jpg

Well I tested the control pressure I think. I borrowed a pic from HFR_Racer. I hooked up my fuel pressure gage as shown in HFR's pic. According to my gage, I am at 105 pounds of pressure (7.25bars)!
Unregulated fuel pressure from the pump pins my gage at over 110 pounds (7.5bars plus). I am using a Bosch 984 if memory serves. (It is a big pump we used to use with our outboard boat motors.)
Using the built in regulator I see 105-110 pounds. So that is not working right if I am supposed to see 87-94 pounds (6-6.5 bars).

Am I connected correctly to measure control pressure?
http://forums.pelicanparts.com/uploa...1270842877.jpg

We're not seeing your complete pressure gauge set up in that photo. It appears to me that you are hooked up in the right place, but... The CIS tester gauge I have has a valve. In one position it measures system pressure, and in the other it measures control pressure.

The values you've given sound like system pressure...if system pressure = control pressure, then you've found your problem.

redo
 

Here is what I see if I close the valve. there is no pressure coming from the port labeled 0 psi, and 105 psi coming from the fuel head.http://forums.pelicanparts.com/uploa...1270845165.jpg

Jacob,
It is a 1987 3.3 BTW.

Thanks for jumping in.

Drew

valve closed = system pressure...open should be control pressure. If they are the same, that suggests the WUR is fuched.

Full disclosure: Your '87 has some additional plumbing btw the WUR and fuel head that I think is related to the lambda control. My '79 doesn't have any of that so I'm pretty much clueless as to how that might change the technique to check fuel pressure (if at all).

Are you running the lambda control computer from the 1987?

In your pic, right below the fuel head is the red lambda control valve. It doesn't look like anything is plugged to it.

Even on cars that have lambda control, but with unplugged O2 sensors, the lambda valve runs around 50% duty cycle, if you have nothing driving it, you're AFR is going to be way off.

You could change to an early non-lambda fuel head, or have yours modified to omit the valve and get the AFR's corrected.

Something else to add, running one pump, with that high of a fuel pressure, is usually not efficient and may not provide the fuel you need, no matter how big it is. Single pump flow rates tend to drop drastically at about 5 - 6 bar, thats why Porsche used two pumps on 930's. I'll have to check my book when I get home, but the later models run about 7.4 bar system pressure.

Even the 'big 044' drops flow and draws more amps when the pressure is high:

http://www.lucasinjection.com/580%20254%20044%20flow%20chart.jpg

Have my engine out, so took a picture of the EGR hole jwasbury has circeled out
This hole should be blocked

http://img706.imageshack.us/img706/60/img2706f.jpg

[QUOTE=WinRice;5286307]Are you running the lambda control computer from the 1987? In your pic, right below the fuel head is the red lambda control valve. It doesn't look like anything is plugged to it.[QUOTE]

Looks like the frequency valve as part of an Andial enrichment system, from where/how it's installed.

[QUOTE=mark houghton;5286354][QUOTE=WinRice;5286307]Are you running the lambda control computer from the 1987? In your pic, right below the fuel head is the red lambda control valve. It doesn't look like anything is plugged to it. Yep, I think you're right, it has the stacked banjo fittings. That's what I get for browsing at work.:D

Either way, if that's a stock 1987 head, it has or had lambda, hopefully it was removed and retuned properly.

I read again and realize that the photo is not of your car. '87 did have lambda from the factory though.

Abnormal
 

I guess the inside of a wur is not supposed to look like this.http://forums.pelicanparts.com/uploa...1270851912.jpg

Anybody have a spare lying around?

Ouch! That is nasty looking!