Idle questions, what do yall think (1 Viewer)

[zukinut]

A little background, 1994 FZJ80 with 226k on the clock. Had a head gasket done about 50k ago.

It has always idled low and rough since i got it 8k ago. Sometimes it idles at 400 and sometimes it idles at 600. No matter what speed it idles, it misses and acts crazy. Its not the cable. It NEVER idles high, not even when its 20* outside. It doesnt idle high while the motor is warming up or anything. The a/c will make it idle up tho. It doesnt throw any codes.

Other than the idle, the truck runs awesome. I tow with it and such and it does just fine.

Any ideas, I would rather fix the issue than live with it.

Thanks in advance,

 

[CJF]

First thing to check is always the air intake tube.

 

[zukinut]

Intake tube is new.

 

[ALCO]

ECT Sensor? IAC Valve?

 

[arndog123]

How about the IAC valve since it controls idle speed? I've been meaning to clean the one on the LX because the idle speed occasionally surges up and down when the engine is warming up.

 

[medtro]

According to FSM, low idle could mean problem in:

• ECT sensor circuit
• Volume air flow circuit
• Injectors

 

[dallen341]

A new ECT sensor corrected my low idle problem.

 

[hybric4x4diesel]

A little background, 1994 FZJ80 with 226k on the clock. Had a head gasket done about 50k ago.

It has always idled low and rough since i got it 8k ago. Sometimes it idles at 400 and sometimes it idles at 600. No matter what speed it idles, it misses and acts crazy. Its not the cable. It NEVER idles high, not even when its 20* outside. It doesnt idle high while the motor is warming up or anything. The a/c will make it idle up tho. It doesnt throw any codes.

Other than the idle, the truck runs awesome. I tow with it and such and it does just fine.

Any ideas, I would rather fix the issue than live with it.

Thanks in advance,

pls check the tps setting.

 

[dallen341]

A new ECT sensor corrected my low idle problem.

errr...so I thought. Wrongo Bongo. Still idles @ 400 rpm when warm.

 

[ALCO]

Have you tried injector cleaner?

Or.... to override the issue until you can find the real problem....get a OEM Hand Throttle Cable. Slee has them.
Set the idle where you want. (you need the correct pedal for this)

 

[kidglove13]

Check your timing.
It could be off.
Especially if it feels like it is missing.
you might need to advance your timing a little