How to set idle 5-7 ltr - 1993 Chevrolet Caprice

fuel pump and filter

Make, model, year and engine type and size.

I am chasing this problem also in my 94 Camry. I am investigating

- vacuum leak somewhere in the intake manifolding or hose
- EGR valve malfunction
- IAC valve malfunction
- deteriorated spark plug leads
- head gasket leak
- fuel pressure low from pump
- malfunctioning fuel pressure return or relief valve

if the coolant level is going down you may have an intake or head gasket leaking coolant into the cylinders pressure test the coolant system

Consuming fuel? You now have poor fuel economy? I would start with a tune up. What year is it? Any check engine lights? Does it idle and drive fine

MAYBE CHECK (MAF) MASS AIR FLOW SENSOR

The engine light is telling you that the cpu has detected a faulty unit that is outside set parameters. Code p0301 is a cylinder misfire detected. Possible causes include Engine mechanical fault. wiring. faulty ignition/ fuel systems., injector. ECT(engine coolant temp sensor)/ MAF (Mass air flow) sensor and ECM(engine control module) I would look at individual coils if you have them --fuel pressure test , head gasket Have a radiator pressure test done

Idle air control solenoid, on base of throttle body

Also good spark plugs and a clean rotor and cap will help

You mean idle, after starting or running!

check for vacume leaks and the oxygen sensor if its a petrol engine might need replacing.

try the following, if that doesn't correct it u may need to replace the air bypass valve.
Here is the most common cause of surges and stalls and low idle rough idle, it is the idle speed control air-bypass valve and throttle valve (IAC for short), they get full of gunk over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.