atsronnyats

why in the world would this happen? my idle sucks ok fine for a n/a 88 vert...normal. what i dont tend to think in my opinion to be normal is when i depress the clutch or for the layman press the clutch in (to the floor) why would the car run better pls give me your insight if you have any on that.... to futher explain the car will start rev a lil above 3k rpm then fall suddlely (most times) on its why down though around 2200-1700 (it varies) rpm it will begin to studder not idle bad, rather stutter as if it "wasnt run on all cylinders" i know its a rotory that is my only way with words to make you better understand the literal "stutter" it will do this in a up a down pattern up - down up- down the rpm that is, is rising and falling and varies about 200 300 rpms and usually when it does this it is rising from 1100 rpm. this does not seam to be a symptom of cold nature and/or operating temp. the rev down shakes the car (as it is slower than the rev up) what puzzles me is the fact that it stops if i depress the clutch. now i dont think this to be a matter of the actual disc catching any grip and giving me that shaking b/c the rev up is smooth, no this is something different so i ask you what the **** is going on here pls your thoughts are welcome................anythoughts!

NJGreenBudd

iTrader: (1)

any time your idle hangs around 1,100 rpms the ecu advances the timing and you get that cyclical bouncing idle.

Check this out, this is from my old thread when i had a crappy idle:

Originally Posted by scrip7-

Ok. I duplicated the hunting idle on a '88 TII that I have at work. I manually held the throttle at 1100-1200 rpm and watched the timing. It advanced 6 degrees from base timing and back and forth until I released the throttle. So basically, anything holding the idle that high will cause the bouncing, whether it be thermowax, vacuum leak, tight cable, dashpot, BAC screw, or whatever. It doesn't have to be strictly a bad tps as so many on here have suggested.

Bottom line is: The idle speed must be kept at or under 1000 rpm with the tps set correctly to prevent the bouncy idle. So, in my opinion, when other people have a bouncy idle complaint, the diagnostics should start with:

(1) A visual inspection of the throttle lever to insure that it contacts the stop screw (by using a mirror and flashlight or temporary removal of the intercooler)

(2) If a gap is found between the throttle lever and stop screw, inspect thermowax and fast idle cam position adjustment, dashpot function and adjustment, and throttle cable slack.

(3) With the throttle lever against the stop screw, perform vacuum leak test using the propane method or compressed air method and make associated repairs.

(4) Set timing to spec with engine below 1000 rpm.

(5) Adjust A/F mixture screw (if equipped) to obtain smoothest idle

(6) Adjust BAC screw (if equipped) to obtain 750 rpm idle (or your preferred speed at 1000 rpm or less) and re-adjust A/F mixture screw if required.

(7) Adjust TPS per FSM and re-adjust idle speed if necessary.


It's from this thread:
VIDEO - Still crappy idle, no response to idle adjustment??