ae92 hesitate/misfire

[wbs3375]

hi, i'm from malaysia.

i own a 2hand corolla 89 ae 92 16valve - carb - right hand drive. I own it about 4years.

1. two months ago my engine is overheat.Caused by a/c fan and leak cap. After changed oil/filter its run fine for about one month, then the headache began.

2. the rpm is not stable, bodyshaking at low speed.Engine hesitates regularly. I changed plug and plug cable. Then its run fine for a week.

3. then the clutch pad worn after 4 years- Changed 1 set. Then it develop misfire/hesitates irregularly, sp during third gear. The mechanic dont know the cause of hesitation.

4. Changed distributor cap from chop shop . Test drive it. Still there.

5. Other mechanic changed a small rubber hose between air filter. He open/closed the carb with his hand while revving...The hesitation gone. The car is running fine.. for about a week.

6. Now the hesitation/misfirecomes back, but on a milder note. Other than that, the left drive shaft is clicking when turning (using non-original parts a year ago)

Is there a possible link of hesitation with the drive shaft or carburettor or else ? The mechanic suggest changed of carb. Thank you all.

[wbs3375]

HESITATION - THE STORY
yeap, thank you SEANBY for info.
in my case rolla 89 ae92, the changed parts are, by chronology

1)new set plug cable, no changed
2)new plugs, test drive it, but still there
3)new distributor - the most expensive one, BS, still there
4)new fuel filter, still
5)carb cleaned, yeap still there
6)engine mounting, oh yeaahh, still there
7)another new set of spark plug, migrain coming again
8) a breather hose from air filter to engine changed,.. not again,
8)clutch plate changed, no cure
9)drive shaft greesed again, still
10) my wife suggested new car- I dont want to run from a problem to add another problem.
8)pcv valve changed, for symptom -idle at 500rpm,leak oil-but STILL THERE!

the engine use toyota oil, is smoke-free, the carb has a sweet song and double-cleaned, SO WHAT these professional mechanics doing ?

Okay, I'll found u , mr hesitate. Open again the engine bonnet for 32th time. Check all the wire,the hose,the ORGANS-radi,alternator,aircon compressor (AIRCON?). So desperate now, everything must been checked, spray shaving foam at all links for air-leaks, spray water for electrical leakage..... Let the hand do the walking... ooops whats that- like a goose pick my hand - it's like an eletrical shock, wanna to kill me ehhh, BAST****, have already kill my purse, no more money there for u moron. Check the pug cable for the 2nd, third time - YESSS !! .

To test bad cable, touched them at last for 5 minutes during engine idle. Its intermittent , remember,, at least 5 minute with idle engine, better still ask a driver friend to revvv.WIth bad cable it will shock u to death. Either u or your money. Dont ask the wife, she might kill u accidentally.


REASON: My trusted mechanic has changed THE PROBLEM CABLE, WITH ANOTHER NEW PROBLEM CABLE. Just imagine the unnecessary cost if I follow his advise to changed carburettor, my friends advice to changed engine, and my wise wife to changed the whole CAR ????!!!

But he don't know yet, because I'm a real gentleman. I will bring back the rolla to him during weekend. Since I'm a better PLUG-CABLE mechanic than him, in future, I will choose and set the cable myself. Instead, I will ask him to changed the steering rod link for a steering vibration. . and a free cable, of course

[Hemi3TC]

If your 89 AE92 is a carby, it may still use a vacuum switch mounted somewhere. Mine is mounted on the right fender, 82.
If the vacuum switch is not operating properly the first fuel cut solenoid will not be opening up properly and this will lean the
air fuel mixture and cause heisitation. Just like your car is running lean.

At low vacuum the vaccuum switch may not be properly on/closed to open the solenoid. At high vacuum it opens/off and closes the first fuel cut solenoid.


good luck
Hemi3TC

Originally posted by wbs3375
HESITATION - THE STORY
yeap, thank you SEANBY for info.
in my case rolla 89 ae92, the changed parts are, by chronology

1)new set plug cable, no changed
2)new plugs, test drive it, but still there
3)new distributor - the most expensive one, BS, still there
4)new fuel filter, still
5)carb cleaned, yeap still there
6)engine mounting, oh yeaahh, still there
7)another new set of spark plug, migrain coming again
8) a breather hose from air filter to engine changed,.. not again,
8)clutch plate changed, no cure
9)drive shaft greesed again, still
10) my wife suggested new car- I dont want to run from a problem to add another problem.
8)pcv valve changed, for symptom -idle at 500rpm,leak oil-but STILL THERE!

[Deep]

So it was a bad plug wire? What a pain in the ass.

[wbs3375]

Hemi3TC, Thank you very much , for your very important info.

If the not the cable, I shall go to the vacuum switch as mentioned by you, as my car has been overheat before.

[wbs3375]

hooray !! Its confirmed my previous observation. A new plug wire set that cost only 75% than previous "new" problematic set.

Conclusion: In any case of misfire/hesitation, replace the plug wire set and get the plugwire set by yourself at the store to esnure it's quality that could be determined by it's look and feel. Go for the best brand that you could buy. DIY is very easy. If hesitation continue after replacement, go check again the plug wire set. Make sure the contact is good and the spark plug is NGK.(no marketing here)

[Flashmn]

Best wires = OEM Stock toyota wires, they work better than any other.
Best plugs = Denso Plugs, NGK causes misfire as it ages