Idle Help

[cowmoo32]

When the engine is cold in my car, it won't idle at all. After it warms up, it'll idle ok, but not very smoothly. My friend who used to own it said it's going to need an idle control valve. A couple questions:
1. Is it the idle control valve that's causing this?
2. Do I need the T shaped or the L shaped valve?

[gedupsound]

When the engine is cold in my car, it won't idle at all. After it warms up, it'll idle ok, but not very smoothly. My friend who used to own it said it's going to need an idle control valve. A couple questions:
1. Is it the idle control valve that's causing this?
2. Do I need the T shaped or the L shaped valve?

you need a T-shaped one if you have a t-shaped icv, and an L-shaped one if you have an L-shaped one. Does your car have an icv at all, is that the reason you ask? otherwise it should be pretty obvious ;) It may not be the icv at all though, some investigative work may be a cost-effective way for you to find out. Im sure someone has outlined how to find out on here.

[nando]

test your coolant temp sensor first. if it won't idle when cold that's usually the culprit since the ECU needs to know how cold it is to enrichen the mixture.

[jlevie]

A hot rough idle and a really bad cold idle sounds like an intake leak. You could also have an ICV problem, but a sticky ICV tends to cause a surging idle.

[FlyingPrick]

test your coolant temp sensor first. if it won't idle when cold that's usually the culprit since the ECU needs to know how cold it is to enrichen the mixture.

+1. also check the tps.

[klayvon]

I'd check your O2 sensor, cold start valve, thermostat, and thermostat sender as well as the aforementioned parts.