Alright, While the car is running, most times when i turn on AC/Defrost. If its as soon as I start it, or press in the clutch and go into neutral, like while sitting at a light. The RPMs will drop to 400-500. When it normally just sits at 900. Now I know there is the slight draw when turning on the AC and the car corrects itself to compensate for this. But it seems like every other time I'm driving it, it does this to me. It almost dies every time, so I have to turn off the defrost. If I don't it will just sit there and fluctuate between 800 and 400rpm, sometimes it will drop to 400 and then die, and then other times it will drop to 400rpm and then go back up to 900 and act normal.. It's pissing me off, because then sometimes it won't act up at all the entire drive. Then next time I drive it, it does it again.. and I have no clue as to what would be causing this. I've replaced the IAC valve and cleaned out the port with no luck. and I'm not going to try to explain and come up with predictions to what I think it could be, i will let you guys shoot me some suggestions first.
Any help is appreciated, If I can't seem to get a good tip I guess i'm left with taking it into the dealer.
Oh btw the Fuel Pump was replaced 2 weeks ago at a shop due to it dieing on me and wouldn't start, they told me this problem was IAC and I decided after all the issues I had with them I'd do that myself.. and what do you know, they were wrong.
Edited 1 time(s). Last edited Sunday, February 21, 2010 5:37 PM
get another car, problem solved lol
Do you have the reflash that is supposed to correct this issue? It was mainly for teh automatics but I have in the past done a few 5 speeds and it fixed the issue.
map sensor maybe? tps? thats all I could think would cause that sensor wise if the iac is good.
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I have a 5 speed. I got the reflash back in 04. I was having slightly the same problem. Push clutch in, and rpm's drop. I also had the rpm's climb up to 1500 on occasion before the reflash.
i seem to remember having this problem after i put the turbo on my car tried to tune it with larger injectors and a 2.5 bar map sensor. every time id be driving with the ac on and id come to a stop in neutral it would bog down to about 400 rpm and sometimes stall out but when the ac was off it ran fine. If your running a stock tune and all I'd start with checking the ac pressure sensor and map sensor out.
there was a reflash for it? i have a similar problem...when i turn on ac, my rpm's drop a few hundred, but my acc doesn't engage...talk about weird. gotta figure out whats up with my electrical clutch circuit for my ac, but why would the rpm's drop down? what did the reflash do?
mitdr774 wrote:Do you have the reflash that is supposed to correct this issue? It was mainly for teh automatics but I have in the past done a few 5 speeds and it fixed the issue.
anymore info on this reflash clyde? I guess I'm pretty well stuck with going to the dealer then.
Mr.Choo wrote:I have a 5 speed. I got the reflash back in 04. I was having slightly the same problem. Push clutch in, and rpm's drop. I also had the rpm's climb up to 1500 on occasion before the reflash.
yep, exact problem I got. interesting, will have to call in about this reflash
Matt C wrote:i seem to remember having this problem after i put the turbo on my car tried to tune it with larger injectors and a 2.5 bar map sensor. every time id be driving with the ac on and id come to a stop in neutral it would bog down to about 400 rpm and sometimes stall out but when the ac was off it ran fine. If your running a stock tune and all I'd start with checking the ac pressure sensor and map sensor out.
Any idea on how I could test the ac pressure sensor without buying a new one first? same with MAP?
Oh and wayde.. trust me If i could afford to I would. I've already parted and sold everything and put this car back to stock.
Edited 1 time(s). Last edited Monday, February 22, 2010 4:04 AM
I dont recall when it came out (I sent a Cav. to Milford proving grounds/tech center for this issue in 03) but there was a program change in one of the many updates over the years for the J cars. Many cars (mostly auto but a few 5 speed) have been fixed by dumping in the latest program available. GM never released a fix for the 2.4 though. I have not been in a dealer since 07, so i dont know if there was ever an official update released after Aug. 07 for this issue.
I'll have to call them tomorrow as this happens to my car as well, although once in a blue moon and only in cold weather.
Both the map sensor and ac pressure sensor are 5v sensors which means both have a +5v wire, -ground wire, and the wire running pack to the computer. But if the map sensor wasn't working right your car should crank out a check engine light just from normal driving. If you want you can expose the wire on the ac pressure sensor and see what the volts being sent back to the computer are... or use hp tuners and log the ac pressure sensor to see if its working properly. If you want i can give you what the actual volts are for the AC on and off are on my car but ill have to get back to you on that.
