Just got a '91 Formula L03

Idles pretty rough but once you break the idle it's really smooth

Anyone have any ideas as to how to fix this?

 

- clean your idle-air-control-valve (IAC)
- replace your spark plugs and wires, distributor cap and rotor
- get a new air filter and fuel filter
- replace your oxygen sensor
- try misting some water into your throttle blades to clean out the carbon in the combustion chambers





does it idle better when the engine is warm or cold?

 

Check the EGR as well. Common symptom for a valve thats stuck open.

 

How do I check that valve?

I also got a code 32 before but it went away

 

You could pull the valve and visually inspect the pintle. If its stuck open then youve found your problem. Not a bad idea to clean all the carbon deposits out as well. After youve pulled it to check the valve, you can also move the diaphram by hand to make sure it still moves freely. Only some of the egr valves can be checked with vacuum. IIRC the negative back pressure and standard types can be checked with a vacuum pump to see if they are functioning.

 

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Yeah... Underneath there is a diaphram inside the sheetmetal housing. It should move when you push it up with your fingers.