J-Body Automobiles Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
37 Posts
Discussion Starter · #1 ·
I need to know where to start. Starts but stops immediately. Fuel pressure 45 before key turn then 35. Fuel filter and pump don't have met before thousand miles on them. Check vacuum best I could. Car has always had idling and some acceleration problems I could never track down. I just need to be pointed in some Direction.
 

·
Premium Member
1988 Z24 Coupe 5spd, 1988 Wagon w/94 Auto Drivetrain, 1992 Z24 Convertible Auto, 1994 Z24 Coupe 5spd
Joined
·
2,678 Posts
A bad MAP sensor can cause the symptoms you described. But I think it would have thrown a code.
 

·
Registered
Joined
·
37 Posts
Discussion Starter · #3 ·
Let me not be lazy "fed up". Car has been problem Matic since day 1. High idle sometimes, sometimes just pouring fuel through it and other times running fine.
After purchased I replaced...
TBS
CPS
Fuel pump, filter, pressure regulator
Injectors have been gone through three or more times. Finding bad ones every time. Last time installed complete reman of 6.
DIS and coils have been changed multiple times with known good ones.
Alternator (take note thick power wire looked like it had been hot at some point and I repair connector)
IAC and MAP swapped off my 87 just to try
Computer swapped between both cars. It runs but no changes. I don't even know if that's a capable swap as 87 has mass air flow sensor and 89 doesn't. Numbers match
Car had new stainless steel exhaust front to back and O2 sensor when purchased

NOW what I tried yesterday
Swapped IAC & MAP again
Tested fuel pressure
New fuel pump relay
Car did start running worse right before it died when I had the stereo turned up. I seen that in the past but thought I was crazy. Head unit was terminated with a connector plug (did not cut factory connector). The only thing on that plug is the dash speakers, memory, power and ground. Rear speakers, subwoofers and amp separate. Very confident in my wiring on that but may have affected it. Smell electrical smell as well. Had been when stereo was up but thought it was just new components getting hot. Almost thinking I need to tear the dash out the car and check all the wiring to the car itself! Keep in mind this has been a fight for 4 years now. Car has 110000 miles. My 87 I hav always been able to repair for 20+ years now. I'm missing something!!! Bad wiring?
 

·
Premium Member
1988 Z24 Coupe 5spd, 1988 Wagon w/94 Auto Drivetrain, 1992 Z24 Convertible Auto, 1994 Z24 Coupe 5spd
Joined
·
2,678 Posts
Sounds like you have already covered nearly everything.

va_subdivisions said:
Check vacuum best I could. Car has always had idling and some acceleration problems I could never track down.
How did you check it for vacuum leak? I like to use smoke, it never fails. Cheap air pump, cheap cigar, a bit of tubing, a rag to stick in throttle body and there you go. Works like a charm.
 

·
Registered
Joined
·
37 Posts
Discussion Starter · #6 ·
Retested with cigar and air bed pump. Have a little bit out of the top of the throttle body were the four lines connect. Also out of the air filter. Can we be honest would that really not make the car run at all. I will fix that as soon as I can find one of them rubber pieces. Guess I forgot to mention I redid the vacuum also when I purchased the car. If anybody has a part number for that 4 connection rubber vacuum piece I would greatly appreciate it. I'm pretty sure the one that's on the car I found the best one I could at the junkyard.
 

·
Registered
Joined
·
2,424 Posts
Can you post a video of it starting and stalling on YouTube? I'd drive down there and diagnose it but I don't think you want to pay for me to drive 300 miles lol.
 

·
Registered
Joined
·
37 Posts
Discussion Starter · #9 ·
This is NOT how it was acting!! Was only running 2 to 3 sec. The time between restarts I am waiting for fuel pump to stop. Seems like longer than it should be. I'm also not touching the gas. Sounds like some small backfire a few times.

 

·
Registered
Joined
·
37 Posts
Discussion Starter · #11 ·
Funny I was looking at throttle body's last night. I had remembered a post like that one. May have even been the same one. Will a 3.1 body work on my 2.8? Looks the same but I know that means nothing. I THINK I had swapped that at one point too from my 87. Not sure but that's been in the back of my mind. What about intake or head gaskets?
 

·
Premium Member
1988 Z24 Coupe 5spd, 1988 Wagon w/94 Auto Drivetrain, 1992 Z24 Convertible Auto, 1994 Z24 Coupe 5spd
Joined
·
2,678 Posts
Yeah, it should work fine. You'll need to do an idle relearn , of course, but I don't think there will be an problems. The set screw is supposed to be set at the factory and then plugged. So, it may be off slightly, but the ECM should work it out. It is worth trying, just to see how it runs with it.
 

·
Registered
Joined
·
37 Posts
Discussion Starter · #14 ·
I got it!! Injector tested at 3.8 ohms. Checked it 3 times. Had one of the old one's I kept that was good. That's the forth time I have had to mess with injectors. When I got the car there was 3 different brand of injectors all mixed up. I'm going to try and find a reasonably priced NEW set. Also going to get new MAP and try and find a better vacuum set. I may be able to get a low mileage Body but it's off a 3.1. That's why I was asking. Would that be OK or should I find one for a 2.8? Anyway THANKS!!! I was about to get a 5 gallon gas can and a match.
 

·
Premium Member
1988 Z24 Coupe 5spd, 1988 Wagon w/94 Auto Drivetrain, 1992 Z24 Convertible Auto, 1994 Z24 Coupe 5spd
Joined
·
2,678 Posts
Fantastic! Glad you found the problem.
Be careful buying injectors. Some are being sold as one thing, but come as something else. I ended up buying a set through Summit that was shipped from one of Standards facilities. $230 or so for the set. Those are the real thing. The part number for the set is FJ105RP6. These are pintle type.

You can get cheaper ones. There are Disc types for less. Standard even makes a set of them, the FJ105T. They class it as a budget line, hence the 'T'.

Here is a good video of the two types of injectors for a 2.8L running side by side.

I don't think you'll have any problem using the 3.1 TB either.

The gas and match are only a last ditch effort :wink:
 

·
Registered
Joined
·
46 Posts
I couldnt help but giggle when I read this thread. Have an 89 vert too. Had issues replaced just about everything, still not right. CHeck out my posts. Just got a new prom today, going to try it out. If it runs, selling as is, spent at least 2G. I LOVE THIS CAR but Im fed da f up

GL with yours :)
 
1 - 16 of 16 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top