6G Celicas Forums

Hey all,

Hate to say this but I had not started/ran my car for 6+months. So I decided to get her started and do some maintenance. Before I started her I changed the oil and filter. Had to jump her to get here started, but after that all was fine (battery practically brand new). It has a very small amount of fuel left but did not fill her up with new fuel yet.

Ok, so here is what I noticed. Driving experience was great aside from the brake pad noise. She did not sputter nor was there a hesitation in acceleration (1.8L so I don't expect much). One thing that I that took me off guard was when I stoppped (still in drive) her idle was so soft/quiet that I tought the engine was about to die. 3Years Back: I got my timing belt changed and I noticed afterwards that it had a slight vibration when stopped / in park, but it never really phased me. Vibration can be "seen" through the steering wheel. Back to the Present: So I just chalked up the restart experience to me not being use to my 1.8L. So I got out left her running / in park, thats when I noticed I could see vibration (moderate shaking) on my trunk lid. Traced it back to the exhaust which then I traced back to the engine... which makes sense.

Long story short: The idle is so low that it is causing an engine vibration. Its like it has found harmony between idle and nearly koncking out. Right now she is idling at ~500-600 rpm.

Fuel filter has been replaced before (~3yrs ago) and PCV valve. As far as I know my throttle adjucstment has never been tampered with. After all this brain storming I regapped/cleaning up my spark plugs... made a very slight difference.

My biggest worry is ?maybe? my timing belt job was done improperly. Again I think she has HAD this problem ever since that time belt job... I think. But everyone tells me its not that (not sure why it can't be that). My distributer and and plug wire have never been replaced. I wish I can see a change in RPMs due to the a/c compressor but my a/c has been out of service for awhile now. Engine mounts need replacing?

I would like to know what I can do myself before I take it to a mechanic. Would like to here someone's diagnosis on this?

THANKS

-Vic

PS: Glad to be back on the 6GC board!

This post has been edited by UTSlickVic: Sep 7, 2010 - 4:41 PM

I don't know the answer, but I also have that problem with my ST.

You can adjust the idle at the throttle body, there are 2 bolts, just adjust them and it physically moves the throttle cable,this will allow you to raise the idle. The shuddering may be because of the low idle. Adjust the bolts and get it idling around 700-900 and then see if its still shuttering. Is it misfiring?If so id tune it up,(oil,plugs,caps,wires,ect) If its NOT misfiring then id take a look at eh motor mounts, as rubber degrades after time..

Yep I think the low idle is causing the vibration. I agree with you about the replacement of anything that can cause a misfires. I guess I will replace the plugs/plug wires and distributor before I adjust anything. To tell you the truth I don't want to mess with the throttle body wire.... yet. I guess I feel like it has nver been mess3ed with beofre, why should I start now. I will get my mechanic to replace the engine mounts, but after that, if nothing has changed then I will start to worry.

Wonder how difficult it is to replace the distrubutor cap?... new territory for me.

Thanks for your advice. Any others?

Adjusting the throttle cable is VERY simple, and you cant really screw anything up that you cant undo in a matter of seconds, the bolts are 12 or 14 mm i believe..You just turn them with a wrench and you will hear the idle either increase or decrease. Then you tighten the bolts up just snug, go look at what your idling at on your tachometer and adjust.Then when you have your preferred idle you tighten the bolts down

Mine idles at 500 as well, but that was after me screwing with the throttle cable, and being to lazy to return it...I was just happy I fixed the stuttering issues =P

^^thats way to low....That equals not enough oil circulation which in turn puts unnecessary wear on the parts and eats your piston rings

mine idles at 1000k for some reason, smooth(intill i put it into drive) doesnt sound like its idling high or anything but my friend has an st with a 5 speed and it idles with the clutch in at like 5 or 600. i was told before i bought my celica that alot of celicas have these problemes( i personally have no clue)

The 7afe should idle at 700-1100..Anything higher or lower causes unneeded wear on the engine

This post has been edited by SupraKid: Sep 7, 2010 - 6:52 PM

Yea I agree it is, but I don't have long term goals on this engine. Much less the desire to fix any future failures.

Yea its a simple fix, but eatting my rings up..well it is a 7afe with 155k+ on it...those rings are long worn. You can ask the white smoke when I start her up everyone morning. Runs like a champ, and it will continue, until I swap the beginning of next year.

But for the ones that do wish to keep your engine in prime condition..yea, I would fix it.

mine did that the other week it was idling really low i thought it was about to die, but i thought well hey its 100 degrees here so it could be that. and my engine shakes, first thing i assumed was the engine mounts, so i'll try the throttle body cable and let you know

Well I filled her up with premium and poured in some VV fuel injector cleaner. I've been driving her as much as I can and it has made a slight difference. In Drive/Park stopped she is idling @ 600 RPM exactly.

SupraKid is the 700 - 1100 RPM band a factual range? If not, I'm contiplating calling toyota and asking if they know what is the ideal idle range for a 94-99 Celica ST.

I will say this the vibration seems almost non-existant now (at least while stopped/in drive). She is VERY SMOOTH while driving and at a stop light. I was thinking this is as close to an electric car feeling as I can get (I speculate)