Help with '75 914 Fuel Inj

cjdeck · 06-13-2010, 09:09 AM

Hoping you guys can help me, I did a clutch on a '65 912 w/ a '75 FI 914 motor (1.8 or 2.0L). Motor was out on a stand and some degreasing and painting went on. Motor is now back in all hooked up but will only run on starter fluid. I was very meticulous with every wire and hose hook up, so I'm 99% sure it all got reconnected. Have fuel at the pressure regulator. It would seem that the ignition is OK as it will run starter fluid. I'm thinking the injectors are not getting fired by the module?? Could water during the cleaning process compromise any thing obvious??

Any thoughts, please let me know.
THANKS ! ! !
Chris

racer · 03:17 PM

well.. iirc, the '75 1.8 used an L-Jet FI system and the 2.0 used a D-jet system. I neverl learned the L-jet system, but it IS different than the D-Jet.. so knowing which you have should help diagnosis.

As I guess, I am thinking electrical.. FI trigger points perhaps? Bad ground somewhere?

cjdeck · 06-14-2010, 08:19 PM

Honestly I don't know which type it is. I found some info on line that has value but nothing hard and fast on exactly it's from. I was told it's a '75, thats it. Thanks for the ideas. I'll look into the grounds. Where are the mentioned FI trigger(s)? You're not talking about the distributor points, are you? I pinned out the 24 pin ECU connector and it all checked out good.

Thanks again,
Chris

Dave at Pelican Parts · Dave at Pelican Parts's Garage

D-jet has a silver hand-grenade looking thing on the right side of the engine bay. It has one hose and a bundle of four wires going to it. The 2.0 liter version has a throttle body that is up and down and sits on top of the manifold.

L-jet has an air flow meter over on the left side of the engine bay attached to the square air cleaner housing. The AFM has a quarter-circle "bump out" on the side of it, and a bundle of four or five wires that plug into it.

The VIN of a 75 model year 914 would start off "47529..."

--DD

cjdeck · 06-15-2010, 04:04 AM

It's likely a D-Jet then. The "hand grenade" is mounted on the left side in this '65 912, but other than that the description is accurate. The throttle body is in the front of the engine just toward the right side, laying flat and in line with the intake manifold (vertical butterfly plate & pivot shaft).

Thanks DD ! ! ! Any ideas why it would ONLY run on starting fluid? Fuel pressure is steady at 30 psi when firing on starting fluid. Is it time to check injector flow?

Thanks again,
Chris

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Sorry, I spaced on the 912 mention.

If the throttle body is laying flat, the intake is from a 1.8 or a 2.0; but the "hand grenade" MPS (double-check, one vacuum hose from the manifold, one four-wire plug) says it's D-jet.

If the MPS is not plugged in, the injectors won't open. If the trigger points at the base of the distributor are not plugged in, the injectors also won't open.

There are other possible causes, but those are biggies.

--DD

cjdeck · 06-16-2010, 05:35 AM

Appreciate the feedback and info. I'm struggling here. What I know is:
- The fuel presure is spot on at 30psi.
- The ECU connector pins out with flying colors suggesting all sensors and wires are "good"
- A noid test light on the injector harness blinks, confirming the ECU is firing the injectors.
- Gas does come out of the injectors but I'm not certain on flow.
- The engine runs on starting fluid ! ! !

The big question I have is: If the engine run os starting fluid is the ignition good?

cjdeck · 06-17-2010, 03:29 PM

It's alive. I finally eliminated enough stuff that the only thing left was fuel quality and supply. The car is running.

Originally I avoided a lot of areas like fuel quality thinking that an engine drop out and replacement shouldn't affect certain things. Anyway, I pulled the fuel supply and return system apart, cleaning from the tank supply hose to the injectors. Then flushed the supply line out w/ compressed air in the filler neck. Then rebuilt w/ clean parts. Ran the pump, draining the end of the fuel rail into a catch pan. Rust colored at first then clear. Buttoned it up and it fired after a little coaxing. Runs a little rough but I think I can tidy that up. The owner will have to decide what he wants to do about the rusty tank. Thanks again for the help. E-mail me w/ questions in the future as I've learned a lot about this motor and FI system.

Chris

CWDECK@verizon.net