95 Z28 Starts but wont stay running
09-22-2010, 08:54 PM
#1
95 Z28 Starts but wont stay running Didn't get a lot from searching which kinda surprised me.
So im working on my friends z28 in attempt to get it to run. He is in the marines and away from the car and im his only source to get it running.
Late last year he replaced plug/wires, and the fuel filter.
He came back and was gonna take the car back with him but wound up stuck at a gas station his first day back with a car that wont start. No biggie we replaced the starter and walaa. Then we did some little maintenance stuff like change the oil, coolant, etc.
We go to leave and the car won't stay running. He drove the car literally 15 minutes before it stopped running. Start but no run.
I noticed the fuel pump was barely working so we went and got that and it helped enough that you can keep it running if you peddle it, but still wont stay running on its own. Kinda backfired a little too.
So then I changed the MAF. It was able to stay running by itself but at ~500 RPM's which is way low. It only did this once. I gave it a little gas to see if it would rev up and idle at the correct speed. Nope died. Backfiring pretty much stopped unless you revved it to like 3 or 4 grand.
I'm gonna clean the TPS tomorrow and see if it helps any.
Any other thoughts of what it could be? Please don't tell me opti!
EDIT: Car is an Auto that's bone stock and there's no check engine light on.
So im working on my friends z28 in attempt to get it to run. He is in the marines and away from the car and im his only source to get it running.
Late last year he replaced plug/wires, and the fuel filter.
He came back and was gonna take the car back with him but wound up stuck at a gas station his first day back with a car that wont start. No biggie we replaced the starter and walaa. Then we did some little maintenance stuff like change the oil, coolant, etc.
We go to leave and the car won't stay running. He drove the car literally 15 minutes before it stopped running. Start but no run.
I noticed the fuel pump was barely working so we went and got that and it helped enough that you can keep it running if you peddle it, but still wont stay running on its own. Kinda backfired a little too.
So then I changed the MAF. It was able to stay running by itself but at ~500 RPM's which is way low. It only did this once. I gave it a little gas to see if it would rev up and idle at the correct speed. Nope died. Backfiring pretty much stopped unless you revved it to like 3 or 4 grand.
I'm gonna clean the TPS tomorrow and see if it helps any.
Any other thoughts of what it could be? Please don't tell me opti!
EDIT: Car is an Auto that's bone stock and there's no check engine light on.
Last edited by 4THGENCAMAROFAN; 09-22-2010 at 09:55 PM.
09-23-2010, 07:16 PM
#3
Already tested pressure previously. Has 40 psi after priming and then drops to 35 and maintains that. Is that normal.
ICM tested good.
Plug placement should be fine because it was running just fine about 15 minutes before.
ICM tested good.
Plug placement should be fine because it was running just fine about 15 minutes before.
09-23-2010, 07:51 PM
#4
TECH Fanatic
Maybe post a video if possible of how it acts and we can determine it a little easier. Good Luck!
09-23-2010, 08:51 PM
#7
On The Tree
Join Date: Jun 2007
Location: Bristol, TN/Knoxville, TN/Mooresville, NC/Phoenix, AZ
Posts: 191
Likes: 0
Received 0 Likes
on
0 Posts
Sounds like a symptom of plugged exhaust, could be something else easily though.
Fuel pressure spec from haynes manual:
key on, engine off - 43-47psi
key on, engine running - should drop 3-10psi
If you think it's ignition then all that's left beside the opti is ohm'ing the ignition coil, and going through the ignition coil wiring and opti wiring. Procedures for that are on Shbox's website or in a Haynes manual.
Fuel pressure spec from haynes manual:
key on, engine off - 43-47psi
key on, engine running - should drop 3-10psi
If you think it's ignition then all that's left beside the opti is ohm'ing the ignition coil, and going through the ignition coil wiring and opti wiring. Procedures for that are on Shbox's website or in a Haynes manual.
Trending Topics
09-29-2010, 09:19 PM
#8
Sounds like a symptom of plugged exhaust, could be something else easily though.
Fuel pressure spec from haynes manual:
key on, engine off - 43-47psi
key on, engine running - should drop 3-10psi
If you think it's ignition then all that's left beside the opti is ohm'ing the ignition coil, and going through the ignition coil wiring and opti wiring. Procedures for that are on Shbox's website or in a Haynes manual.
Fuel pressure spec from haynes manual:
key on, engine off - 43-47psi
key on, engine running - should drop 3-10psi
If you think it's ignition then all that's left beside the opti is ohm'ing the ignition coil, and going through the ignition coil wiring and opti wiring. Procedures for that are on Shbox's website or in a Haynes manual.
10-06-2010, 04:07 PM
#9
UPDATE:
Ok just out of curiousity I went out to the car and tried starting it with the MAF disconnected..it ran FINE....absolutely perfect!!
So I reconnected the MAF...died
Disconnected the MAF again...ran FINE again!!
What does this mean? Bad MAF? I just put a new one in but I guess it's possible.
Ok just out of curiousity I went out to the car and tried starting it with the MAF disconnected..it ran FINE....absolutely perfect!!
So I reconnected the MAF...died
Disconnected the MAF again...ran FINE again!!
What does this mean? Bad MAF? I just put a new one in but I guess it's possible.
10-12-2010, 05:33 PM
#11
Ok I decided not to get it since i'd rather have a 6 speed. So i'll probally just do an LS1 or LT1 swap into my RS.
However, he will be back in EARLY November and I would like to get it running by then that way where not trying to figure out whats wrong with it at the last minute so he can drive it back.
However, he will be back in EARLY November and I would like to get it running by then that way where not trying to figure out whats wrong with it at the last minute so he can drive it back.
10-14-2010, 10:49 AM
#13
It's obd1.5, meaning it has the obdI software but obd II connections. I beleive this is how it is from the seaching and reading ive done throught a couple of forums and what not.
10-14-2010, 11:02 AM
#14
Launching!
iTrader: (2)
Join Date: Jul 2010
Location: Ann Arbor, MI
Posts: 210
Likes: 0
Received 0 Likes
on
0 Posts
well, i could be wrong, and I'm not saying I'm not. But, I was at the shop I used to work in and they had an obdII scanner, and I had to use an adapter to plug into my car. I was told it was because it was an OBDI port on my car. As stated in other posts, I'm fairly new to this stuff, so i could be completely wrong.
10-14-2010, 10:19 PM
#15
Ok so we took the car for a drive(he came back early) and under 2000 rpms it would run fine with the maf disconnected, but if you tried to get on it it would just sputter and slowly accelerate. With it in park and not under load it revved up to 4000rpms just fine.
We also changed the MAF again to see if it would help but the same symptoms are present.
We also changed the MAF again to see if it would help but the same symptoms are present.
10-14-2010, 10:22 PM
#16
well, i could be wrong, and I'm not saying I'm not. But, I was at the shop I used to work in and they had an obdII scanner, and I had to use an adapter to plug into my car. I was told it was because it was an OBDI port on my car. As stated in other posts, I'm fairly new to this stuff, so i could be completely wrong.
