Hey fellas, new to the site but not to an engine bay. Still I've got a few problems here and I'm running out of knowledge and don't want to throw money at the situation. Here's what I've got.
85 RE motor with the multi-port fuel injection.
-Recently replaced injectors, fuel filter, fuel pump and strainer,
- re-wired the pump as there was no +12 to it
- new plug wires
Compression was as follows:
190 PSI for 1-3, 175-180 for #4
Fuel pressure was 40PSI with an experimental pump that I tried, but I put in a stock replacement pump and assume it to be in the range now.
Good blue spark at all 4 plugs. (pulled each wire and grounded against the block while trying to start)
Vacuum is 25 in HG but here's the rub.
The engine will not idle for more than 30 sec. and when it does, it's like it's got an extreme miss. Sounds like one out of the 4 is actually hitting. If you can get it to rev up it's butter smooth and will stay at 2000 or above (no tach, just by the ear of it) but as soon as you decide to let it back down it's the same old story, no idle and chug chug. To get the Vacuum number I had to rev it up and release the throttle to produce a "like idle" condition, but this may be an artificial number, feel free to weigh in on this. What running it has been doing looks to be rich, as it turned the plugs black with carbon soot.
I'm thinking timing, as I've read that these engines can have a weak timing chain set, but that you usually hear it rubbing against the timing cover and I don't hear that. Also I miked the engine and hear no tapping from the top or bottom end. The only thing is what I had to do to get the engine to make a vacuum number, and that the engine will only run on the test pump, will not fire at all on the OEM replacement. sorry about the long post and any help appreciated.
85 RE motor with the multi-port fuel injection.
-Recently replaced injectors, fuel filter, fuel pump and strainer,
- re-wired the pump as there was no +12 to it
- new plug wires
Compression was as follows:
190 PSI for 1-3, 175-180 for #4
Fuel pressure was 40PSI with an experimental pump that I tried, but I put in a stock replacement pump and assume it to be in the range now.
Good blue spark at all 4 plugs. (pulled each wire and grounded against the block while trying to start)
Vacuum is 25 in HG but here's the rub.
The engine will not idle for more than 30 sec. and when it does, it's like it's got an extreme miss. Sounds like one out of the 4 is actually hitting. If you can get it to rev up it's butter smooth and will stay at 2000 or above (no tach, just by the ear of it) but as soon as you decide to let it back down it's the same old story, no idle and chug chug. To get the Vacuum number I had to rev it up and release the throttle to produce a "like idle" condition, but this may be an artificial number, feel free to weigh in on this. What running it has been doing looks to be rich, as it turned the plugs black with carbon soot.
I'm thinking timing, as I've read that these engines can have a weak timing chain set, but that you usually hear it rubbing against the timing cover and I don't hear that. Also I miked the engine and hear no tapping from the top or bottom end. The only thing is what I had to do to get the engine to make a vacuum number, and that the engine will only run on the test pump, will not fire at all on the OEM replacement. sorry about the long post and any help appreciated.
If there's nothing clogged or sticking in the intake, then, yeah, check your timing.