I've been driving my 92 Sc for some time now with everything working normally power and accelration quite fine. The other day i noticed that at idle it would bogg down and jump up. I thought instantly, " vaccumm leak" changed out some hoses and it idled better but still would do it. I didnt think to look for codes because there was no cel on yet I tried anyways with a continuous blink, I took to be normal if there's no codes on. I took her for a spin and during first and second gear it would do it while driving. Imagine a vaccumm leak idle while driving then it picks back up and does it again untill im over 45% throttle. Im fresh out of ideals henceforth it does it while driving as well. And I might add its bad during start off even on throttle , goes to 300-500 rpms then drives fine. any suggestions would help not wanted to replace everything if not needed.

 

Does anyone have any ideals at all, any help would be appreciated

 

Could be a lot of things but check your IACV and TPS.

 

That's actually what i started with and replaced that entire throttle body twice now. Thanks for the feedback though.

 

the tps sensor has to be adjusted...i'd start there

 

I attempted to adjust it but efforts seemed to have failed henceforth it did the same thing. I will relook at it,it couldn't hurt thanks.

 

Did you do a resistance check as well on the tps and iacv?

Is your car a sc300 or 400?

Wouldn't be a bad idea to do a throttle body cleaning as well if it's never been done.

 

its 1 of two things, If it happens at idle when its cold or when you turn the wheels its your IAC either out of spec or needing to be cleaned.

if the stutter only happens under load then its your tps

ive had both problems....

also why did you replace the whole tb assembly? seems pointless when you could just unscrew 4 screws and have both the IAC and TPS off in minutes

 

@V8drummer: I did check the resistnace on the tps, which after reading today via internet I adjusted it wrong. To be honst i didn't think to check resistance on the IAC I grabbed one from a junkyard that was running figured it'll be a quick fix. I have a 92 300 I'll have pics up soon as I get the right angle. and I also tried that as the first step (tb cleaning) thats what lead me to purchase another.

@SJ408: I thought It would have been an open and close case basically, the throttle body was 100, that hurt later. And it actually does both whether warmed at OT or cold. So i will most definitely take another look at this which thanks to both of you I have a better perspective on.

 

Might be time to look at the small stuff. Hows your air filter? Plugs, wires etc?

 

Next step i did a change not to long ago, Im waiting untill i have a true few hours to devote to it and go from there. I'll be posting my findings once everythings cleared which will hopefully be soon