New to 914's - ignition question?

[bobswei]

I just picked up a couple project 914's. Both 2.0L's. One starts up and runs good. The other (with rebuilt engine) wont start. PO thinks it's in the dizzy but I swapped them from the running car. I also swapped the coil from the other car. I can't see a spark (when I crank with one hand and hold a mirror with the other to see in the engine compartment). I set the timing by flashing the points and that sparks seems kinda week, though it's been many years since I've done it that way. When I picked up the car from the PO, we checked spark at the coil and seemed like it faded away after a few seconds. It did "try" to start a few times.
Any ideas what to check next? I feel like it's something simple.
Thanks, Bob

[beatnavy]

Ignition troubleshooting, like all troubleshooting really, requires a methodical approach. Here's a decent methodology: Ignition Troubleshooting.

Fortunately many of the ignition components aren't terribly expensive and are worthy of general maintenance/replacement anyway. If the wires, dizzy cap, points, condenser, and plugs aren't new, consider replacing them as a good practice anyway. Then start looking at battery (is it fully charged?), dwell (are the points actually opening and closing?), grounds, and other wiring.

If you correctly "flashed" the points then you probably have most components in place. Are you getting spark at the plug when your crank the engine and ground the plug to the case? Sounds like you either need a better mirror or a helper.

[bobswei]

Thanks Beatnavy,

I just went through all the test procedures from the trouble shooting link you sent. All seemed OK except the test where you test with points open and check for voltage across the + and - terminals on the coil. I see some voltage which would indicate bad points or condenser. But they work in the other car. Hum?? All plugs and wires are new. I guess it wouldn't hurt to have new points and condenser too. I should have a result to these parts later today...
Thanks....

[bobswei]

Update: New points and condenser and still wont start. When I flashed the points, spark seemed a "little" stronger, (maybe). But yea, I need a bigger mirror. Hard to tell if there's a spark at the plug when my arms is stretched out as far as I can with a little shake in it. I'll find a helper and double check everything.....
Thanks

[bobswei]

Seems, after new points, condenser, wires that I don't have ignition issues anymore but now have fuel injection problems. I will start a new thread for that.....

[walker67]

The other (with rebuilt engine) wont start. PO thinks it's in the dizzy but I swapped them from the running car. I also swapped the coil from the other car.

[Dave at Pelican Parts]

Are you getting fuel? Does the tailpipe smell like fuel after you've been trying to start the car for a while? If carbed, do you have fuel in the float bowls? If injected, are you getting fuel out of the injectors? (You can put them in jars and crank the starter with the spark disabled to see.) Are the plugs wet with fuel when you pull them out?

How about compression? Does the starter motor sound like it's cranking unevenly? Do you have a compression tester to check with?

The engine needs spark, air, and fuel to run. Make sure those are present. If they are, then the questions are the timing of the spark, and the quantity of the fuel.

It's sometimes possible to get the distributor in 180 degrees out. (Don't ask how I know this.) It shouldn't be, because the drive tang is offset, but sometimes it can be done. Or the plug wires can be in the wrong location. If you have spark and air and fuel, this is definitely something to double-check.

--DD

[bobswei]

Update: Had it running yesterday, very rough, with a miss. Today, I found one injector not working. I swapped connections and still, the same injector not working. Can they be rebuilt or new one? I did check CPS with a vacuum meter and it holds. Plugs are wet (and black) with fuel after the first start. But will not start a second time. Just kinda stumbles a little. I think I will order a CHT sensor and an injector and try again. If I can keep it running with all 4 cylinders, I can check timing better.
Starter motor seems to crank evenly. I did check one cylinder for compression and was around 100 (cold obviously).
More updates after parts arrive. Thanks.
Dave, I think I used to autocross with you in GGR back in the late 90's. Glad to see some GGR folks from my day still around. Bob Beach

[beatnavy]

Yes, injectors can be serviced. There are several places that do it. Mr. Injector (Mr Injector - Home) is a good option, and for $17/injector (roughly) it is a good use of time and money. Just pop them in an envelope and send to him with a form (and credit card #). It's hard to effectively troubleshoot when you have a lot of components about which you're unsure, including injectors.

Have you checked your vacuum hoses? If they're misrouted or if you have vacuum leaks you can get really rough running as well. I didn't see what year car you have. Here's a reference for lots of good info. Look down the page for vacuum hose layout for a 2.0 for your car: Jeff Bowlsby Tech Notebook.

Just for reference, here's a picture of a CHT on an engine without the tin. It is just to the right of the #3 spark plug. You won't see it, but you can see the wire lead coming out of a hole in the tin. It may not solve all or any of your problems, but it is a part that definitely can cause problems and a variable that can be eliminated (assumes the wiring is good on it too).

[Dave at Pelican Parts]

Bob, your name sounds familiar, but it's not connecting with anything in my head. I might recognize you if I saw you--I'd be more likely to recognize your car from then...

A few of the folks from back then are around on here; Sergio is "PCA7GGR", Winders is "winders", Mike M. is "mahler9th", and there are others that you might recognize. I've seen them on the Racing section of the forum; there are probably others around in other sections as well. I still have that light-blue 914...

Replacing the CHT can be a pain--it is somewhat buried under the engine tin, and with a steel sensor threaded into an aluminum head, it isn't hard to strip the threads. Penetrating oil can be your friend on this.

100 PSI sounds like more than enough compression to start, and if the cranking sounds even that's a good indication.

Replacing injectors is easy. There are a number of places that will do the cleaning and/or refurb, another one I've heard of around here is Witchhunter Performance. The better places will replace the screen in the inlet of the injector, they may replace the pintle cap, and they'll all flush the injector with solvent and generally document the flow and spray pattern.

Have you read through Brad Anders' D-jet Bible? Brad's '70 914 2.0L Has lots of info on what makes D-jet tick, and some troubleshooting info as well.

--DD

[bobswei]

Another update: I think, maybe the CHT may be a minor issue. I checked all vacuum hose connections, found one that needed a place to go. Then installed the air cleaner to finish the connections. No start. I started playing with timing and realized that the points plate was rotated to one side. I have the vacuum advance module disconnected so I have easy access to dizzy nut and adjustment. I rotated the plate to the other direction and the car started but still very rough. Sunday will be my next chance to work on it but will try to reconnect advance and start from there. Also, there is a red wire coming up from beneath the throttle body that's not connected to anything. Any suggestions?
Dave, I'll try and find an old photo from back in the day and scan it. Sergio was one of my first autocross instructors. The Nidels still around? Rob, Sherily, etc...) Lloyd and Patti DeMartini, Bob Cross, Richard Jung (914) etc.... I was always at the Pleasanton Fairgrounds, Candelstick, Santa Rosa airport, Crows Landing, Alameda, etc...
Thanks

[beatnavy]

Red wire under throttle body... Auxiliary Air Valve lead? Can you take a picture? Dave might know this off the top of his head. What year is your car? You can check out the electrical diagrams here: Electrical Diagrams.

Once you confirm you have vacuum hoses, ignition wiring and functioning components, and fuel items hooked up correctly (or close) you really need to check valve clearance, then dwell, and then timing. If you can't get to valves just yet, at least confirm the dwell (45-50) before attempting to fine tune the timing.

[Dave at Pelican Parts]

Sounds like you need to refurb the distributor. You shouldn't be able to just push the points plate around, it should be spring-loaded.

The red wire is most likely the one to the AAR. Non-critical; not plugging it in will mean your idle will go up for a while as the engine warms up and will come down slowly after that. There will be a single white wire (tied into the fuel pump power circuit) that plugs into it.

The Neidels are still around. I just recently saw photos of Sharon at the last Redwood autoX up at the airport, in fact. We have lost most of the local autoX sites, though. There are still very occasional events at Alameda, but almost all of the PCA events are down at the Marina Airport near Monterey. But the Santa Rosa Airport site is still going strong. (We lost it for a while, but eventually were able to get it back.)

--DD

[beatnavy]

I think Dave's right. Your dizzy probably also needs work. Here's a thread I used for reference to service mine. Starts about post #35. Dizzy Maintenance.

[bobswei]

Here's a photo of the red wire and also a plug that I don't know, what plugs into it (circled in red).
Hum, the dizzy came out of the running car (1975) but I'm sure this one is not spring loaded. This car is a 1974 I'm trying to get running but dizzy's look identical. Today, I'll remove the dizzy and go through it. If I start on the things I know are wrong, the rest may be simple. I hope...
Thanks for the helpful links and direction. Updates to come soon.....



Here's a video of me at the Santa Rosa airport. I haven't found any old pix yet. The second half of the 90's, I built a race car, (and it started without all this trouble) and got into the time trials. I seem to be able to get 911's to start.
https://www.youtube.com/watch?v=0TQjyhWVA0c

[beatnavy]

Ja, the red wire is going to the AAR. As Dave said, it's not critical at this point based on where you are in tuning/troubleshooting. It's used to help assist warm-up and the upshot is your idle may be higher for a little longer during warm-up process. The part you circled in red is the Air Intake Temperature Sensor (T1 sensor, I believe). It adjusts fuel mixture for ambient air temperature. As Anders says on his D-Jet website, it has a minor impact on fuel mixture. It's not nearly as critical as CHT and MPS, but it's another one of those things that you should address eventually.

Nice video!

[bobswei]

OK, so I can put loose ends (wires) on the back burner for now. Today, took the dizzy out, cleaned, lubed the cam and put back together. Nice to have your link to show how it should look (which mine did). The points plate spring is actually from the vacuum advance diaphragm so that is back on. Re-installed, set timing and nothing. Decided to revisit the fuel injectors and now, non are squirting. I know the fuel tank was low so I added about a gallon and I can feel the fuel lines vibrating with fuel flowing but injectors aren't doing anything. I believe the lower set of points in the dizzy provide the pulse for the injectors? So, I will reject them on my next chance...
Thanks for the input..... Bob

[Dave at Pelican Parts]

Make sure the fuel pump is pumping. You should hear it go "buzz" for about 1.5 seconds when you turn the key from "off" to "on". If the wire that should plug into the AAR wire is shorting to ground, it will pop the fuse on the fuel pump power circuit. (That's one of the two on the relay board.) That wire is a single white wire that comes out of the ignition harness.

--DD

[beatnavy]

Yes, the electrical plug with three leads attached to the back of the dizzy is for the points. If that's not plugged the injectors won't fire. You can test with an injector removed from it's position (but still connected to a fuel line). Insert the business end of it in a glass jar and turn the ignition on. As Dave says, the fuel pump should prime for 1.5 seconds. Then crank the car for a couple of seconds to see if you get any fuel firing into the jar. If not, it's probably one of the following: pump not working, fuel pump activation circuit problem (relay, fuse, etc.), clogged filter, bad or disconnected points, injectors leads not plugged in, etc.

How are your grounds? There should be a three spade connector on the top of the engine, at the back near the flywheel. That's a multiple point ground. Make sure those leads are very clean and well connected.

[bobswei]

I know the fuel pump is working but it stays on the entire time the ignition is on. No 1.5 seconds, then off. Fuel is getting to the injector because I pulled a fuel line off and gas pours out. I've already gone through the cranking with injectors in a container. All dry.
I unplugged the lead (3 wires) going to the dizzy trigger points and one wire has power (tester lights, photo).



I put that same connector on one of the injector leads (tried both wires) and turned the tire while in 5th gear and it didn't light. Not a good test? Or, maybe the black box on the side of the throttle body with the harness plugged into it?
I will check grounds tomorrow but the "look" ok. Battery needs a charge tonight.
Thanks for hangin in......