Mechanics

QUESTION ENGINE IDLES HIGH AND STALLS

1999 Isuzu Rodeo

Engine Performance problem
1999 Isuzu Rodeo Question 6 cyl Four Wheel Drive Manual 150000 miles

hey 2 car pros-

This problem has been gradual. For a long time, my car would idle high. It would stall after long trips of 100+ miles. It would run fine around the city. However, after longer drives, when slowing to come to a stop, it would stall, even before I'd reach a complete stop. To trump this problem, I used to glide into stops and rev the engine to keep the RPMs up, almost as if to keep pressure or gas in the engine to avoid the stall.

Also.
About every 5th time that I start the car, it will idle higher than normal at first. The engine will almost rev, but this will eventually settle and the car will run normal after a few minutes.

Coming home yesterday, the engine stalled near my home. This morning it will start, but the car will stall almost immediately if I leave it in neutral.

In search of the problem I have replaced the Fuel Filter, IAC, MAF, and Cleaned the Throttle Body as best I could (however, I used IAC cleaner because I had it in the garage). I have also replaced the Fan clutch 6 mos ago.

I would like to get my car working again. And I'd love to fix this problem. Where do I go from here?

thanks
chris brecht
Avatar
ChrisBrecht
July 6, 2010.



Hi ChrisBrecht, Welcome to 2carpros and TY for the donation

Lets try cleaning out the EGR and PCV valves and then test the throttle position sensor and the MAP sensor

Rasmataz
Jul 6, 2010.
I never got to the EGR.

The PCV valve looked okay.

The problem was the Throttle Position Sensor. I unplugged the sensor and started the car. It didn't stall with the sensor unplugged, so I replaced the old one. $27.99. Not bad.

Car is running much better. Thanks.
Cb.

Tiny
ChrisBrecht
Jul 6, 2010.
Hey 2 car pros -

so in response to your response, I have since driven to denver with my rodeo after replacing the throttle position sensor. The car ran great through the city, but once again as soon as I got it on the open road and drove 100+ miles, it stalls when I come to a stop.

I'm beginning to wonder if this problem is not related to sensors and connected more to my catalytic converter. Does this seem logical to you?

**Just a reminder, I have replaced MAF, Idle Control Valve, Cleaned the THrottle body, and replaced the throttle position sensor.

This car only stalls after driving 50+ miles on the highway.

It sometimes idles high.

I'm reseting the computer today.

Thanks
chris

Tiny
ChrisBrecht
Jul 25, 2010.