Lumpy Idle?

[wesbeech]

OK my buddie has a 88 supra turbo. It bone stock except i just converted it from auto to a w58 5speed and sold him my 3in ceramic dp and 3ss dp back no cat no muffler. when the car is cold or not fully up to temp when he starts it it idle so lumpy it almost stals and some time dose and even after driving the car it will still idle like this till it gets up to temp. Any body have an idea what is causing this?

 

[jetjock]

Yeah, I dose. Problem with warm up enrichment. Maybe a shifted coolant temp sensor. No codes for that but he should check for others anyway.

 

[wesbeech]

Yeah, I dose. Problem with warm up enrichment. Maybe a shifted coolant temp sensor. No codes for that but he should check for others anyway.

What do you mean a shifted coolant temp sensor?

 

[TurboStreetCar]

Cold start injector maybe aswell.

 

[jetjock]

I mean a shifted coolant sensor. You know, someone shifted it to another engine. What do you think I mean?

Can't be the CSI because it's impossible for it to operate unless the engine is cranking and if it was mechanically leaking the problem wouldn't go away.

 

[wesbeech]

I mean a shifted coolant sensor. You know, someone shifted it to another engine. What do you think I mean?

Can't be the CSI because it's impossible for it to operate unless the engine is cranking and if it was mechanically leaking the problem wouldn't go away.

No clue so check the colant sensors

What about i just remberd it has a gheto wired o2 could that cause it?

 

[jetjock]

No.

Does the idle start off high and come down as the engine warms up?

 

[wesbeech]

It use to do that and when you would first start it up it would idle about 2500 but now it just stays around 800 but is lumpy as hell.

 

[cuel]

Might want to pop over and take a look at the online repair manual, and find how to test the temp. sensor and idle motor. Also tells you how to check for codes, but you have to dig through it a little.

Going to Toyota and ordering the manual so you have one to keep in your car is a good idea, to.

 

[jetjock]

It use to do that and when you would first start it up it would idle about 2500 but now it just stays around 800 but is lumpy as hell.

Well, there ya go. The coolant temp sensor is also used to determine cold idle. Check for codes. If none measure the sensor's resistance or voltage when cold. He could also have an ISC problem but I'm betting on the coolant sensor.

 

[wesbeech]

Well, there ya go. The coolant temp sensor is also used to determine cold idle. Check for codes. If none measure the sensor's resistance or voltage when cold. He could also have an ISC problem but I'm betting on the coolant sensor.

Would that be the green plug coolant sensor?

 

[jetjock]

I think so. Regardless, it'll be the only one with two wires. And take cuels' excellent advice about the book...

 

[wesbeech]

I think so. Regardless, it'll be the only one with two wires. And take cuels' excellent advice about the book...

I actuly have a factory service reapair manual