Hi everyone,

Firstly, I know this is a Z28 board but, I thought I could still get some help with my 91 RS 3.1 v6.

About a month ago I drove a short distance (less then a mile) to a store and without problem. After fifteen minutes in the store I returned my car would not fire. It would just crank and not fire. The next day when the tow truck arrived I tried to start it and it fired right up. I drove it home no problem. I have driven it since then off and on a little bit like every couple days just for short trips without problems. Maybe 15 trips with a total of 20 miles.

Then last week I drove it to a friends house around the block and then when I left I got about a half block away and the car died. The lights and radio still worked just engine died. It would just crank and not fire. I had it towed and two days later I tried to start it again for the first time and it started right up. I then drove it to my parents house about 6 miles away and made it there but, when I tried to leave it would not fire and only crank.

I did get it to start again and had it die twice while test driving around the block.

I then checked for spark which it has, I unhooked the MAF sensor and it did not help. I checked all fuses. Then I checked the fuel pump. It turns on when the key is in the on and when turned to start. I unhooked the engine side of the fuel pump and turned the key to on and fuel pumped out, it also pumped out when turned to start.

I checked the timing and it was at "18" so I figured it was time to change the chain. So I installed a new timing chain and gears with the alignment in :dot to dot: configuration. After putting it all back together I was able to start the car and I let it idle but, after about eight minutes it just died cleanly, not like a loss of fuel or anything just a clean die like all the other dies.

The car seems to start if I let it sit for a few hours and sometimes will be drivable for short distances and sometimes will just die right away.

Any help would be appreciated.

regards, Jeremy

**UPDATE** So it wants to start, it fires up but, then immediately dies, like within less then a second. I tried holding the pedal all the way down then starting but, it wont even fire that way, it seems flooded when I do that.

Also, could someone tell me the steps to check the diagnostic lights on this? Its not odbII. Can I just buy a odbI scanner somewhere or can I do that paper clip thing? I just dont know how to do it.

 

Another update. I took the plug out of the oil fill cover and cleaned off. I then started the car and it ran for a few seconds then boggled out and died. I tried it a few more times and had it boggle for about 15 seconds before eventually dieing, seemed to idle just above 10 mphs during this.

 

ok, I think I found the problem. I was going to change the oil and after loosening the oil drain bold some watery liquid came out, after further examination I determined it was antifreeze. Well I am guessing bad head seal. great...that is going to fun and expensive I am thinking.

 

New update. Ok I checked compression on the spark plugs and they all read 180 so I am no thinking blown head gasket, I replaced the plugs, they were covered in soot, running rich. After replacing the plugs the car turns on good and idles nicely but after about ten seconds the engine revs up on its own a bit then the car dies....

I am thinking the computer is getting a bad reading from a sensor and is trying to compensate with more fuel? Sound likely to anyone? I am trying to bypass the computer but have not figured out how to disconnect it, if anyone knows that would help a lot.

 

yet another update. I pulled SES codes. One was 34 - MAF or MAP sensor and I also got a 42 code.

Also when I fired the car on this morning the first time after sitting all night it started right up and idled fine for about a minute then I shut it down because I saw smoke coming from the engine. it wasn't much and was on the drivers side. I suspect it was some of the motor oil I spilled on the intake earlier. When I got out I also noticed white smoke coming from the tail pipe when it was running and a few drips of water. This leads me to suspect blown head gaskets but I checked the compression yesterday on all the cylinders and they all were at 180.

I am lost now. I replaced the rotor bug and cap, but I also am suspecting the coil part and ceramic part is bad on that distributor. The car wont fire up all the way anymore. It wants to fire but dies after the key is returned to on position. Would a bad distributor cause these symptoms?

 

If it was a bad dizzy most likely it would not pass a spark test. If there's antifreeze in your oil then your head gasket is gone. gasket won't necessarily compromise compression. usually when you lose compression it's a valvetrain issue, not head gaskets. That's just what I've seen. And head gaskets will cause those kinds of symptoms. My mom's old car did that when her head gasket blew. So I would replace that. It's really not that bad as long as you can get the heads off easily. just make sure you get every bit of the old gasket off. Good luck.

 

SupplySGT, thank you for your reply. Ya I don't think it would be too hard to replace the head gaskets, just more then I was hoping. I will check into it and let you know..Again thanks for the reply.

 

no problem. PM me if you have any problems I'll get that message faster if I'm out and about (goes straight to my blackberry)

 

little update.

I did not redo the head gaskets yet, I am not thinking they are the problem anymore. The smoke I mentioned earlier has went away. Anyway this is the current symptoms.

In the morning I can start the car right up and it will idle about 10 to 15 seconds. I am able to give it gas and it rev up nicely. Everything sounds and feels great but then after that 10 to 15 seconds it just dies. No backfiring, no sputtering just dies as if I turned the key off.

After it dies that initial idle and dies I can crank it tries to fire up but jsut wont anymore. I can wait a few hours and it will fire up again for 10 to 15 seconds and then die. I am not getting any codes.

I reset the prom in the ECM, it looked fine but I tried it anyway, no change.

I redid the pick-up coil and ignition module in the dizzy along with the rotor bug adn cap. I replaced the ignition coil too.

My spark pugs I just put in a few days ago were fouling with carbon so I put some new ones in, they are already about fouled and I just put them in last night. I notice that after pulling one after trying to fire they are wet with fuel. I am not sure if this is because the car has not warmed up and I am trying to start it cold or not.

I disconnected the O2 with no change in problems.

So with these symptoms I am kind of stumped.

I think its either...
ECM
Injectors
VAT system
or a short/grounded wire somewhere

I am leaning towards ECM or VAT because it will run after a few hours for 10 to 15 seconds then just die and wont fire up unless I wait. I wondering if the vat system is locking em out for a while or something, really odd.

regards, Jeremy

1991 Camaro RS 3.1 V6 - Stock

 

If your plugs are getting fouled that quickly I would check two things.

First check your fuel pressure... it could be too high causing the engine to run way too rich. If it is too high it sounds like your fuel pressure regulator is stuck closed and needs to be replaced or a possible problem with the vacuum line that controls it (leaking, not connected or incorrect routing)

Second, how many miles do you have on this set of fuel injectors? They could be really dirty and the fuel is not atomizing correctly or just worn out and needs to be replaced. Only replace them after you know if your fuel pressure is good.

 

sorry

 

Limitedr1, I would suggest a seperate thread on the subject as the OBDII 3.8L V6 is a completely different motor than the 91 3.1L OBDI motor. That way we can keep from hijacking the OPs thread here.