Alright, well I just got my car back from 2 months of non sense. My plugs, coil, opti, waterpump all messed up. Well, I got my car back two weeks ago and it ran great, better than before. Got it dynoed yesterday and it put down good numbers, numbers that wouldnt hint that it was messed up.

Anyway. Today, took the girlfriend to the movies and when we were leaving it took four cranks to get her goin. Turned it off and this time it took two times to turn over. I hit it down and it ran pretty strong, raced a fellow z28 and ran strong.

We got home and I turned it off and started it, almost stalled out. Went inside for 45 minutes and then left my girlfriend's house. Started up no problem. My girlfriend followed me home and she said there was some dark smoke coming out of my right exhaust pipe. I guess I will list some symptoms.

1. Several cranks to turn over and start
2. Dark smoke (didnt see it, but girlfriend did)
3. Low rumble and vibrating at low rpms, could just be paranoia


Remember, car was just fixed and ran strong yesterday.

 

Other than cranking issues.... how was the idle once it got started?

 

The first time I noticed it went up to about 1300 rpm. Then went back to right under 1000 rpm. I checked it the last time I started it tonight and it was where it should have been.

 

sounds like an intermittant concern. I'm wondering if the coil wire is fully seated. That would explain the intermittant crank-no starts.

But with one bank on one side running rich (your girlfriend said black smoke on one side) then I'd be looking at more localized ignition issues. If it persists, pull the plugs on that bank and look for any fouling on the tips.

Good luck.

 

Thanks, I wasnt sure if it was the sparks. I hope it is something small, I just through a 1000 dollars worth of repairs at it. Anyone else have any ideas?

 

Well, dont these cars have y pipes? Which means that you couldnt determine whether one bank was running improperly by which tail pipe some bad exhaust came out of?

Which model do you have?

I am not trying to sound like I know anything about these cars, I am a mustang guy that just bought his first 1995 Z28.

Black smoke generally means rich condition..check to make sure you are getting spark and not too much fuel. Check to make sure you have no exhaust leaks before the O2 sensors. Check to make sure you have no vacuum leaks.

But I am willing to bet that there is one signle problem. I am going to guess there is an igntion issue.

Ignition problems could cause it not to start and cause it to run rich.

Again forgive me if I am sounding like I am a know it all....I am just trying to help. If I am wrong in any sense about something, let me know. I just got my first Chevy about 3 days ago and already am having TONS of problems and trying to work them out.

I am having overheating and some incredible oil problems. ;P

Good luck and what kind of numbers are you puting down. I am looking to find a way to make some good numbers with this LT1. I have heard that it can be done but as of yet, I am still trying to figure out what parts are worth while and what are not for these chebbies.

 

Yeah, I guess I should say its a 94 z28. Only mods are in sig.

 

1994 and 1995 had the pipe to one side then split into two. That is odd that you would only have smoke on one side. 1996 and later had dual exhaust.

 

I'd look at your injectors as far as the hard starts. Maybe one or a couple are leaking badly. Also possibly the O2's. But a stuck injector would flood a cylinder and cause a hard start where O2's I thought only kicked in after the engine warmed up.Also would cause the rich conditoin you talked about.

Also no 4th gen camaro/firebird came with "dual" exhaust. All came with catback systems with two exhaust tips but no pipe per bank.

 

I dont have stock exhaust, I am running an off road pipe. The smoke usually came out at a stop sign when I would first start going.

 

might want to research this before posting. No Fourth gen F-body came with dual exhaust, the 96+ had dual catalytic converters in the Y-pipe, but still they joined into a single pipe just like the 93-95.

 

I appologize. I do own a 1995 Z28 1LE and it has the y-pipe that went into a single pipe and split into two at the muffler

However, I got into a heated discussion with a guy on here who had a 1996 and his friend had a 1995. He essentially swore at me that I called him a liar that there were no true duals. But he was so sure of himself that when he dropped his pipes and did an install that they were true duals. Go figure. I'll take your word for it.

Correction noted.