89 Corolla shakes, stalls - Toyota Nation Forum : Toyota Car and Truck Forums

mikehong · 02-08-2005, 06:56 PM

Hi everyone,
My 89 Corolla shakes while stopping at signal. It has a carburator. If airconditioner is turned on, it shakes more and sometimes the engine stalls.
The engine was replaced with imported used one two years ago. It's getting worse everyday. I replaced the battery with brand new big one three months ago. And the alternator too.

karazy · 02-08-2005, 08:33 PM

It sounds like the idle is too low.

mikehong · 02-08-2005, 09:59 PM

Idle can be changed by itself? It was OK untill two month ago. And gradually it changed. Sorry, I have to add that it's ok when the engine started cold.

karazy · 02-09-2005, 03:43 AM

Yes, it can be adjusted. The choke will raise the RPM until the engine warms up. It could also be caused by a dirty air filter, clogged jet, or fouled plugs/cap.

Flashmn · 02-09-2005, 04:48 AM

sounds like a broken aircon idle up

Apo11o · 02-09-2005, 11:58 AM

mine does that when its cold, but the older corollas have that problem from what i have heard, but if its doing it its warm so i would guess its the idle, but im no expert

mikehong · 02-09-2005, 02:45 PM

How do I adjust the idle to high position?

KnightX_AE86 · 02-09-2005, 03:11 PM

ya mine does the same thing but the only diffrent is that mine is not on carb. its jerks after the engine warms up... i dunno wuts wrong with it

karazy · 02-09-2005, 03:43 PM

*warning* It has been over 15 years since I have touched a carb and have never even seen a Toyota carb.

Tip: You should make sure that the plugs and cap are good and make sure car is at running temp, before starting.

If you have the specs, it would be nice to set both screws to proper position to start. If you don't it's ok. With the filter casing removed, you should be able to see two slotted adjusting screws. One should be attached to the throttle cable bracket (fast idle stop). The other will go into the carb to adjust the mixture rate. The mixture rate should be adjusted first (for a smooth idle), but you can play with the throttle to see if that is all that may be required. Just turn the mixture screw in or out to get the smoothest idle. If it still too low, adust the other screw to increase the overall idle.

Remember how many times and the direction that the screws are turned, incase the problem is more severe and the original settings are required. It shouldn't take more than a few turns of either screw.

Once the idle has been set, run the AC to make sure more adjusting is not required.

Anyone with more experience can feel free to jump in at anytime.

mikehong · 02-09-2005, 08:17 PM

Karazy, thanks for your idle instruction. I just found out that engine runs smooth while gear is in park position. If I move gear into drive position with my foot on brake pedal then the car shakes.

karazy · 02-09-2005, 08:31 PM

Most cars do that, including mine. My RPM doesn't change when this happens though. What is your RPM with the AC on in park?

mikehong · 02-09-2005, 11:32 PM

My car doesn't have rpm gage on instrument panel.

90 GP · 02-11-2005, 07:11 PM

Check for any vacuum hoses that are leaking, or loose. That might account for the roughness and slower idle speed.

mikehong · 02-14-2005, 05:26 PM

Sorry for late reply but I had to figure out first what is vacuum lines an part. Anyhow to my eye they look ok.