02-26-10, 12:15 PM
I drove about 100 miles this morning in the snow storm we're having here to Erie, PA from Cleveland, OH. While getting off the freeway I got stuck in some snow that hadn't been plowed on the off-ramp. I shifted into reverse to back out of it and then not realizing any of the tires were still spinning in the snow, I shifted into drive! The car jerked a little bit but seemed fine all the way up until I arrived at my destination.
A couple of a hours went by and I was ready to leave, went to the car, started it and noticed the 2000rpm idle. I tried to backup, needless to say, that did NOT work! The engine stalled out so I shifted into drive, it jerked a little and I drove 100 miles back home after I checked the oil and looked underneath the hood.
The car didn't overheat and it ran good on the freeway but I did notice that it seemed to get stuck in a higher gear a couple times when slowing down.
What could this problem possibly be? Could the PCM P0741 error code be related the high idle?
02-26-10, 10:05 PM
Update your profile so we know what vehicle you're talking about. All we know is that it's a N* :)
I think the code you're getting is caused by the TCC failing, which does have an effect on your rpm. How long have you had the P0741 code?
02-26-10, 11:50 PM
I put the model and year in the subject, it's a 99 STS. I didn't have the code until this morning, I checked the codes after I drove back to Cleveland.
02-27-10, 12:14 AM
Sorry, I missed that. What that code means is that your TCC is stuck off. Was everything good until this happened? I wouldn't think what you did would ruin the transmission.
Try disconnecting the battery and resetting the entire car. That way any electrical fault will be resolved. If there's actually been damage done to the TCC, then you may need to have it looked at/replaced.
02-27-10, 08:44 PM
The car was running perfectly fine and I didn't notice anything strange until after I started my car to leave and drive back to Cleveland, that's when it I noticed it idle 2000+RPMs.
I cleared the codes, drove my car a few miles to Autozone and had them check the codes again, nothing popped up. I'm thinking the P0741 code popped up only once because of me shifting with such a high idle.
The guy at Autozone suggested it could be an "Idle Air Control Valve". I unplugged it just to see if there would be any changes, the car actually idled slower at about 1300-1400RPM. I plugged it back in and the car idles at 2000+RPM. I went ahead and unplugged it for the ride home, it actually seemed to run and idle normally in drive.
Could my problem be the Idle Air Control Valve? Unfortunately they didn't have any in stock.
02-27-10, 09:05 PM
Very well could be. High Idle is a symptom of the IACV not functioning properly. If you drove home with it unplugged, and the idle was normal, I would say you need a new IACV.
I just don't understand how doing what you described would have an effect on the IACV :hmm:
Did you try disconnecting the battery + reconnecting?
02-27-10, 09:14 PM
Maybe the valve just went bad during the 100 mile drive to Erie, but I didn't notice anything until after what I described.
I did disconnect the battery twice, once for a few minutes, didn't do anything.
02-27-10, 09:25 PM
I'm leaning towards a bad IACV. I have no idea why it would go bad, unless you have no record of the TB being cleaned.
02-27-10, 11:47 PM
Remove the IAC and clean the tip and throttlebody passages with throttlebody cleaner (has a different chemical base than choke cleaner).
A new one is big bucks.............
02-28-10, 12:29 AM
I'm going to go ahead and try cleaning it. I just put a new Idle Air Control Valve in and that didn't much good, now it's idling at 3500RPM!
02-28-10, 10:48 AM
Hmmmmmmmm.........While its "idling" at whatever rpm - disconnect the TPS and see what happens. Clean that connector, too. A faulty TPS will cause all sorts of rpm hiccups.
Check your throttle cable for kinks and binding: with engine and key OFF slowly and deliberately depress the accelerator pedal to the floor several times. Is there ANY stiffness or jerky movement ? That cable should feel smooth as velvet.