jliddle

I am having a few small issues with my 93 3vze. One of the issues was before the coolant fixes below..

I had a coolant leak on my bypass block a while back and removed everything but the heads and replaced with all new gaskets. The coolant leaks are now fixed, but a previous issue still remains..

Problem 1. This problem existed before I changed out the gaskets a few months back. When I start the truck when its cold it will idle fine, then idle down to a semi-fast idle speed. I do not have a tach but I know it should not idle this high. As soon as I tap the gas ( while motor is still cold) it throws the check engine light on, symptoms while the light is on is very sluggish response and little-to-no power. I can turn the ignition off then turn it back on and the light goes off. Once the truck gets up to temp, it doesnt do it as often. Recently it started throwing the light on if Im barely on the gas just cruising. It doesnt happen when Im in the throttle more than 1/8th.

I know about jumping the diagnostic terminals and counting the flashes but im unsure on how it would work on mine because of the light going off when I turn the key off/on. IIRC the truck has to be off, then turn the key on to count the flashes. Could I do this while the truck is running? Say if Im driving down the road and it throws the light, Can I drive it to my house and WITHOUT shutting the truck off, jump the terminals and count the flashes?


Problem 2. The truck is idling quite high, and the idle will fluctuate if the truck is warm and idling. I can tap the gas when it fluctuates and it will drop back down to the semi-high idle. But not where it should be. ( Again I dont have a tach so I cannot provide specific details on RPM)

I first thought it could be air in the cooling system but I burped it for a good 20 mins Friday and it seemed to idle fine while I was burping it.

Could there still be some air remaining that would have gotten trapped once I put the radiator cap back on and started driving again?

Or maybe something out of adjustment?\



Any help is appreciated,

Thanks.

jliddle

morning bump

Wrenchinjoe

Idle issues are pretty common on these engines, with lots of causes (i.e. vacuum leaks, dirty throttle body or idle air valve, egr malfunction, cold start injector leak, timing off, sensor(s) gone bad, etc.).

Since you are getting a CEL, I would go ahead and read the codes to see what the computer has stored. With a soft code, the CEL goes out on its own, while with a hard code the CEL remains on until you clear it. Either way the ECM should be logging the error which should help you narrow down the possibilities.

MrPeepers

I would guess vaccuum leak or EGR issue. However, check your idle screw, mine backed out by itself once and caused some weird idle issues and actually created a vaccuum leak.

sb5walker

Engine cannot be running when checking codes. See the "Engine Issues" section of this post for instructions:
http://www.toyotanation.com/forum/sh...3&postcount=22

See the Engine - MFI System - Diagnostics chapter of the fsm for suggestions on the codes, and of course post them here if you'd like help. If you don't have an fsm google 1993 toyota pickup service manual

Check the air hose between the air meter and throttle body for cracks. They like to form on the insides of the accordian pleats of the rubber elbows.

How clean is the throttle plate?

jliddle

I turned this screw clockwise this morning and it seemed to lower the idle. It still has the "semi-high" idle after letting off the throttle, not as bad as it was though.


Ill pull the intake elbow off tomorrow and look up in the TB aswell as check for leaks.

Thanks for the help.