Thread: High idle, decel issues?

This is more than likely your cold air start valve, the test to see if the valve isn't working is to pinch the hose that goes to your intake pipe before the throttle. I have had this problem just change the part, or do the pvc sprinkler hose mod

A can of carb clean and this thread: IACV AAC cleaning and testing tutorial: Nissan Online Mechanic: Nissan Forums and Infiniti Forums - NICOclub

I wouldn't bother trying to take the spring out after stripping the epoxy - more hassle than its' worth and I couldnt find anything that could turn the stupid plastic without stripping it. Fixed my idle issues asap. Try that.

Especially with a warm engine. With the motor warm and running, the air regulator plays a significant role in restoring idle after load. It bypasses the throttle chamber to keep the engine running when the plate closes.



Problem is that when the motor is running and warm, the issue continues. Cold air valve should be fully open once the motor reaches operating temperatures.



I agree. You may or may not find the leak just using carb clean, but some soapy water in a spray bottle works wonders as well. Key thing is that you'll hear it more than see it, since vacuum leaks would be pulling the soapy water into the vacuum galleries and manifold.

^ You have it backwards the motor need more air when you first start it and less to idle after it is warmed up. That is why if you have the pvc sprinkler mod you need to give the car gas on start up on cold days.

well and i think thats obvious on cold start warm up enrichments higher rrrpm idle till warm then you have your base idle speed more air on start up = higher idle speed then base idle speed = less air to maintain the bas e idle speed

but would all this mess with the car bucking back and forth on deceleration?

yes and no - bucking could be a bad maf or bad fpr, or bad tps or bad iacv. get a multimeter and start testing.

^First sign of bucking for me was the injectors. I've had bad MAF's before, but my bucking came from cloggy injectors. Changed them and the car runs smooth.

I did word it incorrectly. Oops!

but he said the driving was completely find except in deceleration. Mine is doing the exact same thing as his, but wot or giving some gas it was fine, the moment i let off the gas pedal, bucking insued