MrJohnTan

Ok, here's the story. I'm borrowing my mom's car for a few weeks. Its a '92 ES300 with about 120K on the odometer. Im driving up to OC from SD (about an hour drive). Everything is running smoothly. At the first stop I make at a light, the engine's revs die down and the car stalls. I start it up and start driving around again. Everything is fine, it no longer stalls as I go from stop to stop. Then I go home (another hour drive) and the car stalls again after I exit.

So basically, the car wants to stall at the first stop after prolonged non-stop freeway driving. After the restart everything runs fine in normal traffic. There are no check engine codes stored on the computer. Any ideas?

lexusk8

Could be a number of things for this idle problem. My bet is on the idle air control motor or valve being defective, but it could also be one or more of the following:

- bad fuel pump ECU
- throttle body is clogged up
- bad MAF (mass air flow) sensor
- bad EGR (exhaust gas recirculation) valve
- might want to check O2 sensors (but usually a CEL lights up when one or more of the sensors go bad)

There might be others but I don't want to waste time banging out the possibilities. Hope this info at least gets your thinking cap on

MrJohnTan

Thank you for your input. I would figure with all the above problems, except for the clogged TB, would throw off a check engine light? I had a faulty IAC on my 86 corolla GTS and it wouldnt idle at all. I had a bad MAF and O2's on my 91 MR2 turbo and those threw up check engine lights...

I will definately pop off the intake hose and shoot some carb cleaner in there and see what happens tommorrow.

Thanks
John <<thinking cap on>>

Overclocker

That’s quite a list there lexusk8, I’d like to add something to it on the simple end. John, have you checked the battery terminals?

They could be loose or dirty and the engine isn’t getting enough juice when the rpm’s are down and the alternator isn’t putting much out.

MrJohnTan

If that were the case, wouldnt the car stall at EVERY stop? It only stalls after freeway driving, when the alternator is spinning at a high RPM and charging the battery.

EDIT: I dont mean to argue w/ everyone's input here, im just trying to brainstorm. I will definately check out the terminals tommorrow.... Thank you overclocker and lexusk8 once again.

Ladie_Lexx

when I leave my car warming up for a few minutes or parked idling for a few minutes I seem to get what I call a "ghost idle" where it will go from 1rpm to like 2.5 rpms on its own with no acceleration. I was thinking of having my o2 sensors replaced and check my throttle body. any suggestions?

Grif

I have this EXACT problem (also a '92), and it's only after a long run and a quick stop (light at end of an exit) that it does this. If I can get through whatever light I come up against at the end of the exit, I'm fine. One thing I've started doing is bumping it into neutral as I roll the last couple of feet to a stop, that seems to keep it from happening.

Because that works, that makes me think transmission, but who knows.

The previous owner of my car said he once had a transmission flush performed (plus a new filter), and that corrected the problem for about 15K miles.

I buy dinner for anyone who could figure out what the true issue is. Nice dinner at that.

MrJohnTan

Well, i tried the easy things first. checked the batt. terminals, everything looks good. pulled the intake hose off and looked at the TB. nothing abnormal there, hosed it down w/ carb cleaner for good measure. I have yet to make a long drive. I will keep you guys posted.

TCwindom

I have a 92 and my car did that too. Check the intake hosing, mine developed a crack over time and created a vacuum leak.

(edit: seems like this has been answered... maybe I need to read more b4 posting... sorry)

mmarshall

Is the air conditioning or front defrost, which turns the AC compressor on above about 40 degrees, on or off when this happens?
If it is stalling with the AC or defrost on, then that may mean that the solenoid that automatically bumps up the idle speed to compensate for AC drag is not working.

MrJohnTan

So I drove up to LA this weekend. Its still happening. It happens whether the AC is on or off.

TCwindom, that is a great idea....I will definately check out the intake hose when I get home.

Grif

A/C doesn't make a difference w/ mine either. As soon as I get mine back from the shop (Rear main seal), I'm going to check the intake hosing.

STAGED

My folks had the exact same problem on their 1992 ES. Namely, the car would stall out after extended highway drives and then when we come to a stop.

There's a service bulletin on this. The problem is in the valvebody and some modifications are necessary (I think the oriface diameter in the accumulator needed to be resized). This prevents the torque convertor clutch (TCC) frm disengaging and the effect is like having the clutch engaged when you come to a stop in a manual trans. car.

Sadly, our Lexus dealer worked on it and after we got it back, the stalling issue was fixed but the transmission shifted poorly. I had that and another Lexus dealer try to adjust the kickdown cable but to no avail. Transmission was smoking vapor out of the vent line and at 90k miles we had to rebuild the trans!

TCwindom

My tranny has been rebuilt... but I don't think that had anything to do with this. If it did, explain to me why when we covered the intake hosing with heat tape it stopped? Now I have a weapon-R intake and it's never done it.

If you want to see what your ECU will do when too much air comes through, disconnect the Mass airflow sensor (little plug type thing on top of intake tubing) while the engine is running. It will stall. I'll take a pic of my old intake hosing next week so you can see the crack I'm talking about. The plastic used on ES's is cheap... and dry rots easily.

TCwindom

Check it well, any crack can pull in too much air. Let me know what you find.