long rev problem

midgetchaser

Registered User
i have a 90 auto and when ever i step on the gas (doesnt matter what gear its in park, drive, netural) the rpms go straight up like normal but the engine takes its sweet time winding down. it revs way longer than any other sc ive ever seen. ive been trying to fix this problem for a long time but i cant figure it out. ive replaced the IAC many times, TPS, cam sensor. Could this be a tuning problem? i know other ppl have this problem has anyone ever figured it out.
 
Just a thought....

Could the throttle linkage be hanging up a little? Check to see if the return spring and lever will move freely. Also check to see if the TV cable (AOD throttle valve) linkage is binding. A good cleaning and some WD-40 might fix the problem.
 
was it disconnected or something? i checked mine and its there securly attached. all of my vacuum lines are where they should be.
 
oh heres a new problem that u guys can scratch your head to. along wiht the long rev issue the car stalls after comming to a stop. it drives fine and sound except for when i am decelerating almost to a stop the car's rpms surge and it eventually stalls this happens almost every time i stop. i had a new Art and Carr tranny just put in wiht a 2300-2500 stall, and the engine was rebuilt about 3,000k ago. does anyone have any ideas?
 
we need to pool our resources
my car did the same exact thing run fine but would die
and it had a high idle that id have to tap the gas for it to come back down to normal


anyone have suggestions?
 
replaced the ignition coil pack that didnt help anything. and checked plugs and wires. still have the problems and a lot of new parts.
 
You might want to research the tps (throttle position sensor) or IAC. It should kick in before the idle drops out. Are you running stock throttle body or aftermarket?
 
stock tb. thats whut i thought, with the tps it would regulate and fix that but i bought a new one last week and no difference. and ive replaced the IAC twice in the last year. thinking that was the problem. i tried to pull codes too but all i got was a 15 read only test fail or something. idk whut that means
 
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I had this same problem on a 93 we had and I replaced just about the whole car but I almost sure that it had something to do with the ECM. Not that it was bad but its values were a little messed up but this car ran at the track with a stock rebuild on the motor and trans, new exhaust mostly from tbird88 and some porting with a cold air intake a 14.4. To bad we never got rid of the hanging rpm`s before idle. If your motor is dieing out sometimes you might have a problem somewhare else. Maybe cam sensor? Don`t you just wish that someone would chime in here and say - yep change this and that will fix it but these cars are not that easy. I was raped 8 times and finaly learned my lesson:eek:
 
After you have replaced parts or worked on the engine it requires to relearn idle.
Disconnect the battery for ½ hour, reconnect, start it up and let it idle for 10-15 min.
If that’s not it, I bet you have a vacuum leak somewhere. Try pressurising the system to 12-15 psi and listen /feel for leaks.
 
the first thing i thought was vacuum leak but i tested it and i have none. cam sensor was changed that had no effect. lately when i have been driving the car if im commin to a stop and it trys to stall i can put it in netrual and the surging rev will stop and it will recover. when i first got it back from the trans shop shifting into netrual would do nothing.
 
me too

mines do that too! I thought that is the way it was with a sc (my 1st) its like a normal car you step on the gas VOOM VOOM, but on this its like VOOOOOOOM VOOOOOOM
 
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