I pulled my 76 2.0 stock fuel injection engine a few months back so that I could plug up some oil leaks. Other than the leaks, the engine was running O.K. Well, as O.K. as I could tell after a couple of weeks of owning my first 914. I put the engine back in just a couple weekends ago and have slowly been trying to get her going again. For a couple of days I could only get her to spin with the starter, but I wasn't getting any fuel.....I figured out today that I hadn't connected the wiring harness to the distributor. Now that I have it connected I cranked her over and I am now firing on just the #3 cylinder. I also don't smell and raw fuel coming out of the exhaust. And when I open the throttle, she seems to power up a little bit, but not much.


major points

76 2.0L D-Jet

rebuilt/cleaned injectors from cruzin performance

new large and small injector rubber

new vacc. hoses all around

just had it tuned up before I needed to pull the engine and I didn't screw with the ignition system at all.

I hear no clicking when I move the throttle switch (thought I was supposed to hear the injectors clicking)


If there are any other bits of info that will help in the trouble shooting process please let me know.

Jim (n00b)

Jim,
Make sure there are no broken ground wires for the injectors at the junction block. The injectors fire in pairs so to have one not firing and no fuel smell probably means that you are either not getting volts, or it is clogged. You can put a noid light in the plug for the non-firing injector to see if it is volts.

Ah, a re-read your post and now see you are firing on ONLY the #3. You need to think about what they all have in common. You connected the trigger points in the dizzy and that would cause all of them not to work, as you discovered. The fact that you can have it running at all means that you have more than #3 firing, but I would start with the ground block on the engine under the air plenum.

What makes you think that #3 is the only one firing? Check the volts to all the injectors. Since they were cleaned the most likely cause is bad grounds.

I have it running on just #3 because I disconnected each spark plug from the dizy one at a time and the popping of the engine didn't change until I unplugged the wire going to the #3 cylinder... the engine died. Plus, I feel pressure coming out of both sides of the engine, but the popping coming out of the passenger side is warmer and more powerful.

Are you sure that the others are receiving adequate spark?

Fairly sure they are getting good spark. Will check again. I don't smell any raw fuel coming from the exhaust, so I am wondering about the injection.

If both sides of the FI fire together, can I swap the injector harness between the passenger side injectors and see if I get the other cylinder to fires?

The injector fire diagonally. I forget the numbering of /4 cylinders, but it is something like 1-3, 2-4. You can try swapping the plug to the next closest injector for a simple test.

The fact that you are not hearing the clicking noises when you throttle tells me that your injectors are not hooked up correctly, though. The clicks you should hear are the injectors all twitching with more throttle via the TPS.

Did you check the grounds? The white wires that attach to the junction that I described earlier?

At the rear of my harness, just to the passenger side just behind the intake, I have 6 white wire exiting the harness. the PO had them all spliced into a wire leading to the negative terminal of the battery. I cut his wire and re spliced it to see if his handy work had been loosened in the process of removing and re-installing the engine. Same cylinder runnin. No Change.

Should I ground these 6 wires to the engine instead of the negative terminal?

Dr, thanks for your help thus far. I now have to go help my Dad do some moving of stuff into storage. Please keep the suggestions coming and I will check them all out when I return in a couple hours.

Ding ding ding! Yup, those are supposed to be ground to one of the screws on the engine case top. 4 of those 6 are the grounds for the injectors, I am not sure about the other 2, but they all should be grounded to the block to start with. They originally had spade connectors on them and there would be a junction for them under one of the case through top screws.

This may not solve your problem all together, but it is a start.

Right on, if I think of anything else I'll post it. I am going to go study neurology now

Otay! I got the 6 wires connected to the male connector on the top of the engine just below the #3 intake runner. I also checked the injector wires be pulling each in turn and testing them with the engine cranking. I get voltage movement with each of them, but the front driver side wires were fluctuating at a higher voltage than the others. And still, even though I am just running on the #3 cylinder she is running stronger now that I have grounded the wires on the case.


Just thinking, #3 is the first cylinder to get fuel. If my pressuer is just low enough, would the firing of the #3 cylinder be enough of a pressure drop to give too low of a fuel pressure for the rest of the injectors?

That question made my head hurt Nope. You should be firing 2 at a time. You may need to check and clean your FI points connector at the dizzy to make sure you are getting good contact to all of your injectors. Check your fuel pressure. If this is off the rest of your efforts will be in vane (vein?).

Since your injector leads are getting voltage, you can easily test to see if your injectors are actually spritzing fuel. A 10mm socket will free the injectors and then just spray them into a cup. No spray + yes power = injector bad or fuel pressure bad. Of course, it would be loads easier to just check your fuel pressure at the rail with a cheap gauge from your FLAPS.

Before I get ahead of my self, is the pressure regulator in correctly? Are your hoses routed correctly? I gotta ask.

OK DrE, thanks for the prescription. I will check the fuel pressure tomorrow as well as seeing if the injectors are squirting.

I will also check the fuel line routing. From memory, comes from pump to the passenger fuel rail then over to the driver side fuel rail then to the pressure regulator, and then back to the tank. Thats how I intended to route the lines. I hope that is right.


Jim

Yup, that sounds right to me. Just check direction of the regulator as well. Here is a link to a diagram on Pelican that Dave Darling did:
http://www.pelicanparts.com/914/technical_...4_20FI_diag.htm

OK, I just finished checking the injectors. I pulled the driver side pair and turned the car over and no fuel spraying. Then I connected my El Cheepo fuel gauge and got a reading of 26 psi.

While I wait for any replies/suggestions, I am going to move things around and see if the wires from the #3 cylinder will fire any of the other injectors.

Jim

Back from my little test. I ran a couple wires across the engine bay from the #3 injection wires and connected them to the injectors on the drivers side (which are pulled out of the intake at the moment.) I turned the engine over a couple times, but neither of the injectors fired.


Any one have a webber setup they would rent to me for a couple months until I can get this wiring FI system worked out??

26 is too low. It should be 29psi and it should hold that setting when the injectors are firing (not drop off). Start there.

So, you said (1) you are getting voltage pulses to the injectors, (2) and you are getting fuel to them I assume.

It sounds like your injectors if they do not open with the pressure increase.

Actually, they should dribble even at the low psi. I am thinking CIS injectors (duh).

Should I soak the injectors in anything to loosen any thing that has gotten stuck while I have been putting things back together? Or, should I try pulsing them with a stronger pulse to free them up?

You can just send them out to be cleaned and tested. Don't apply 12v to them!!

I test them using by pulling em one at a time and sticking the injector into a glass jar to see if it sprays right. I pull the + wire off the coil so there is no spark to ignite the gas spray.
Using a remote starter button I watch the injector inside the glass jar...

If you aren't having any injectors firing check the trigger points inside the dizzy and the connector to it.

as noted its usually a grounds issue for injector not firing.

I suggest that you pull all four of the injectors and put them into similar size glass jars. Crank the engine for 10 - 15 seconds. Check the amount of glass in each jar. The amounts should be within 10% of each other. I use small Mason "canning" jars because they are very sturdy, and I tape them to various components on the engine to keep them from moving. Be sure to have a fire extinguisher handy, since you will be pumping raw gas into open containers on top of your engine.

If one (or more) of the injectors are clogged, you should have them commercially cleaned. I seem to recall that there is a small screen filter inside of the injector. If its clogged by rust, no standard solvent will clean it. The injector place will also be able to tell you if the windings inside the injector meets spec. If your windings are failing, you need to find replacement injectors.

I'm assuming that you have verified the electrical continuity of the injectors back to ground at the back of the engine and the energizing wiring from the ECU, as the evil Doctor suggested. The injectors wires are pins 3 thru 6 in the ECU plug.

Had the injectors serviced by Cruzin a few months back. They were kept in the plastic they were shipped in until I got around to installing them.

I did pull the Driver side injectors and I am not getting even a single drop out of either injector.

I will check the wiring continuity this weekend. I am also going to see if any of the injectors fire when hooked up to my know firing cylinder (#3)

With this long T-Day weekend, I hope to get all of this worked out.

Make double sure you have the gas lines hooked up correctly. Check that diagram on the pelican site closely. If you have the pressure relief valve in the wrong part of the hose lay out, you won't get the propper pressure to all injectors.
Good luck,
Tom

Tom reminded me of the fuel line issue. I forgot (probably because I don't want to admit that I did this), but I once connected the lines to the pressure regulator backwards. The motor would sputter on starting some times; and it would run great for a few seconds when manually primed, but shut down quick.

Like Tom says: be sure to check the fuel line hookups.

OK! Some progress has been made in the diagnostic process. I switched the injectors around to other cylinders on the engine. The injector that was in my #3 cylinder is now in the #1 cylinder and now I am (when it does run) just running on the #1 cylinder. I know this because as I go around the running engine pulling the injector wires the engine keeps sputtering on except for when I pull the wires on the #1 cylinder at which point the engine dies. So I guess this points to my injectors being stuck. I just sent them out for cleaning and servicing from Cruzin Performance. And I kept them bagged until I was ready to install them. They did sit in their bags for a few months because I was moving into a new house, but I don't know why that would have caused a problem.

ANY ANY ANY thing else that I should do/try to test the injectors individually, please let me know. I am at the thread bare end of my sanity. I heard about the guy that used a shot gun to remove a stubborn lug nut. I am about ready to see if his technique will work to fix my FI system.

sounds like a set of known good injectors would be useful for trouble shooting. Cruzin is really good with their service - you probably got back some numbers before and after cleaning - did they indicate there was a significant problem before cleaning? I'm wondering if you have fuel filter problems that is letting crap through that has reclogged your newly cleaned injectors. Perhaps take an injector and hook it up to a couple of D cells - listen for the click. You should be able to easily blow through them with the solenoid open. Don't leave the power applied too long.

Cruzin's report said that one injector was flowing much lower than the other 3. (and I did have one cylinder running leaner than the others) and after their servicing the flow rates were much closer. I will try a couple Ds and see what I hear. If I don't hear anything should I up the voltage to get them unstuck?

I've heard a lot of people say not to use 12 although I'm pretty sure that is what everything runs at more or less. Never the less you want to keep the voltage as low as possible. To tell the truth I used a 6 volt lantern battery and 'got away' with it. I wouldn't really suspect the solenoid is stuck - more likely the pintle or the little filter inside the injector. You are not so much listening for the click - true test is whether you can blow through it.

Well everyone, I have to first of all say thanks for all of your input. When I started this process, I never expected the result to be three bad injectors. With all of the wiring problems I have encountered when working with older systems I figured I just had a bad ground or improperly connected set of wires.

I have been soaking the three bad injectors in cleaner for most of the day now and have tested all four with my compressor and an old 9v battery. the good injector clicks strong and sprays well (at least from my eyeball view) and the other three make no sound at all. Boy on the positive side I din't encounter any leaking.

So, as of now, I am in the market for a set of injectors. I am looking into stock replacement injectors, but am also considering some other newer alternatives like the injectors from a MB 450SE, that I heard one of our other board members has had some early success with. Any other new alternative suggestions are appreciated.


Again, Thanks!
Jim

That sucks considering you had them cleaned I have used ones if you are interested. Cheap and easy

That is most bizzarre. You have to ask the question why they failed and is that condition still present? First thing I would be doing is checking the impedence to see if it is an electrical failure. If they are all the same then I would have a look at fuel delivery to see if there is a bunch of crap floating around in your lines. Not sure how to check for crap but I would somehow want to be sure this was just plain dumb luck before I put another set in.

Dr Evil and I PMed a little about getting me some used injectors from his stash. After things seemed settled with our plan, I went out to my garage and decided that since I had replacements lined up I didn't have anything to loose if I damaged the little buggers. I pulled one out of the injector cleaner that I had it soaking in and, using the hose end like a whip, I beat it against the wooden edge of my workbench. Applied some air pressure and after a couple shots of electrons, it sprayed. I followed suit on the other two who were a little more reluctant to see things my way but eventually they came around to see the light. I don't know how they got stuck or what could have gummed them up after being cleaned, but I am happy that I can move forward now.

swl, I have purged my lines and I have inspected the screens, and found no gunk of any size. Your advise on the pressure flowing through the injectors, and the approx. voltage I should use was a helpful starting place.

Dr.Evil, thanks for all of your help in many ways, and I hope I will be able to return the favor someday for all of you here that lend a hand to others.

Jim