96 camry chugging problem
 

The car:
96 toyota camry 2.2 liter 4 cyl. 155,000 miles automatic
no major engine work yet.

About a month ago after driving around, the car's rpms would oscillate at a stop. But give it some gas and drive away it would be fine again. It seemed like it wanted to stall while idle (goes from like 400rpms to 1k). Well about 2 days ago it decided to poop out and do this when ever the car is running, start up, idle whenever.

There was vibration beyond a normal 4 cyl. It seems like its just not getting enough power.

What I have done so far:
*Bought a car diagnostic scanner it read po302--> misfire cyl. 2 (i pasted the problems from this at the end)

*I've taken off the distributor cap, it looked fine cleaned the very little amount of black build up on the terminals. Everything there looked fine

*Pulled the spark plugs looked for problems:
the first cylinder might have a leak but other than that the color/build up on the plugs looked fine.

*All spark plugs sparked on each wire fine (tested and saw the spark)

*I then put everything back together, now it'll run with out the oscillation of the rpms but the weird chugging vibration is still there. Also the check engine light vanished.

The only thing I can think of is to clean the idle control valve or its a fuel injector.

Any leads or tips of things to look at would be much appreciated






Common Problems that Trigger the P0302:
Worn out Spark Plugs Ignition Wires, Coil(s), Distributor Cap and Rotor (when applicable)
Incorrect Ignition Timing
Vacuum Leak(s)
Low or Weak Fuel Pressure
Improperly functioning EGR System
Defective Mass Air Flow Sensor
Defective Crankshaft and/or Camshaft Sensor
Defective Throttle Position Sensor
Mechanical Engine Problems i.e Low Compression, Leaking Head Gasket(s) or Valve Problems

Can you define chugging vibration better?

The Intake Air Control (IAC) valve controls idle speed. The valve response can become sluggish due to grime the result being idle problems. An internet search on this valve and your engine model should turn up hit on cleaning the valve.

Generally this involves spraying the valve intake with a solvent. Autoparts stores should have them. Find a product that is safe for plastics, the valve is plastic. Don't use brake cleaner!

At times the ECU coolant sensor can fail resulting in idle problems.

The EGR plumbing can plug up due to carbon build up.

The 4 cylinder will vibrate at low idle RPM's

Its a settle chug not like the engine is going to jump out. I'm pretty sure its due to cylinder 2 misfiring causing the harmonic balance to be off thus vibrating engine. After letting the car run a bit to try to hear for something the engine light came back on giving the same p0302 code again. I couldn't find any noticeable vacuum leaks. And its definitely not the wires or the spark plugs. Just swapped spark plug wires for cylinder 1 and 2 and I still get misfire cylinder 2. The idle isn't oscillating anymore.

If it would just make up its mind already