Maybe someone can help me with a rough idle and then stalls. OK, Let me explain what has been done to my 89 Vette, I had this same problem a month ago. I changed the Mass Air Flow Sensor and that fixed the problem. I thought that this was the same problem again. I changed the MAFS again. The car still ran ruff and then would stall - Unable to drive. The car would fall flat on its face then get up and go. While the car was parked I would hit the throttle and the would make it to 1,500 rpm's and then Bog - But not stall. I leave the house and return 3 hours later with a fuel pressure gauge. I have 40 psi, The car ran smooth. I let it get up to temp. At 179 degrees it stalled as if someone turned the key off. Prio to stalling the car was crisp and ran smooth and fuel pressure never dropped below 40 psi. The car started very easy again. I had it running for another 20 minutes and had to turn it off because it is late and I have nasty neighbors. I also looked under the dist. cap and it is clean. This all started today. I did clean the engine with engine cleaner on Monday. I took the car out to dry the engine off on the hwy. I was went up to 135mph, The car ran strong. I parked the car and it was fine. It is like the car caught the flu over night. Can anyone please give me some idea of what my next step should be. I also was tapping the new MAFS while the car was running and the idle did not change. I am sorry for being so long with this post, But just want to give all the details of what I have done and all that is going on. Thanks :confused:

 

IAC valve?

 

Thanks, I will add that to my list to check in the morning. Thanks again for the help.

 

Can you get the problem to repeat itself reliably? According to your post it sounds extremely intermittent. If you suspect the IAC, once the car is idling steady...if that's possible...disconnect the IAC and see if the problem represents itself. It should idle smoothly at a constant RPM with the IAC disconnected and no change in load...no A/C, idle in park etc.

 

This problem just started this morning. The car ran rough when driving to the store in the morning, When driving home it became worse. When I was home it was even worse to where it would surge then stall. It was very hard to get the car to idle. When the car did idle, I did hit the MAF sensor to see if there was a change in idle. This was hard since the car did not want to idle smooth for a few seconds. I did change the MAF sensor with a new one. There was no difference in the idle. I left to go get a fuel pressure gauge (I was gone for a few hours). When I came home, The car would idle fine then just stopped as if someone turned the key off. I restarted the engine and it ran smooth for 20 minutes. I dont understand why it ran better after sitting for a few hours. This is making me pull the very little hair I have out.

 

Hello all, After getting very little sleep last night thinking about what maybe wrong with the car, I started the engine this morning and had it running for about 30 minutes. The engine did not miss a beat. I then decided to take my chances by taking a ride (Hoping not to break down). I went for a ride on the hwy, Just over the speed limit :lol: He pulled all the way up, I then drove home and let it idle for about 40 minutes. When idling in front of the house it did not miss a beat. I guess what was wrong has been corrected. I guess I will never know what was wrong. I am asuming that something got wet when I cleaned the engine and from sitting over night caused something to stick or do something else. I would like to thank all the people that took time out to respond to my HELP Problem. THANKS. I will keep everybody posted if the problem decides to return. :D

 

if the problem returns you might want to check the fuel pressure regulator. Mine had a leak in the membrane and was giving too much fuel to the engine causing similar symptoms.

 

When I had the engine running when it was stalling, The fuel pressure was at 40 psi, When I cracked the throttle the pressure went up to 42psi. Thanks for the tip, I will keep my eyes on the regulator.

 

[QUOTE]This all started today. I did clean the engine with engine cleaner on Monday. I took the car out to dry the engine off on the hwy. I was went up to 135mph, The car ran strong. I parked the car and it was fine. /QUOTE]

Can't help you with your problem but I guess only NYfinest can drive 135 mph in Staten Island to dry his car off :lol:
I had problem with the TPS right after washing the engine. Poor acceleration, bog but engine never stall.
Are you working at the Landfill at all? I like to see your car in person, I'll work there this Sunday (I am with the USACE)

 

I guess the car was tripping no codes? Mine did the same thing, ended up being the MAF sensor. If it comes back look into the MAF relays behind the battery.

 

I don't have anything to read the codes from the car. That will be my next exspense. I also did not know the location of the sensors until you left the post (Thanks). Thanks for the tip. I wonder if the water played a part with the relays. Hmmmm, I guess I will never know until it happens again.

Thanks for the info.

 

I have not worked the dump, I am in a special unit that we are unable to work there. I work in The Task Force. We are a mobile response team. We respond to riots and unusal incidents and other things that may come up. We are needed to be mobile. Well in Staten Island there are only a few places to exceed the speed limit. I have luck at this one location. When will you be at the dump? I know you said the weekend but what day and what tour?

 

All you need is a paper clip and a manual, Haynes or Helms, and it will walk you through diognosing your car. It will at least get you going in the dirrection of the problem.

 

I have the Haynes book in front of me and I don't see anything about the paper clip. I do see the codes. Hmmmmmm Let me look again. Thanks for the tip.

 

I work for the US army Corps of Engineer oversee the contractor. I have my own project on weekdays near Princeton, and the boss assign me working very Sunday lately. Next Sunday maybe the last day I work there. The debris should all be sort out by then. We'll be the last to move out.

 

You guys are doing one hell of a job. That is the least I can say about the work being done. I did the paper clip test. I received a code of 54. The problem with the rough idle comes and goes. I will be racing on Sunday if it is not raining. I race for points at Raceway Park on Sundays. If it is raining on Sunday maybe I will swing by if you will be there. I would just need to know your name so I can ask for you. Thanks for everything. :D

 

I'll be the guy that wear the red shirt with White Castle. USACE trailer office no. (718) 605-2488 ask for Viet. Make sure you have your ID for the police at the front gate and at the road up the hill.

If you're driving the Vette. give me a call and I'll come down. Very bad road for Vette. to climp up the hill:)