This is my first post here, but I have been browsing this board since I got my car 1 year ago. Anyhow, here's my dildilemma.....


Last week my car started idling very rough and didn't even fast idle on cold starts. Well it cleared up a bit, but would drop 200-300rpms just at randon while idling and obviously the lowend and part throttle was missing too. However interstate was fine and now SES light. So fin ally Saturday it threw a light. Diagnosis was p0171 and p0174, both banks lean. That freaked me out, but the scanner said most probable cause is the MAF and have seen where these tend to be problematic from reading these forums.

Today I took off the negative battry cable and cleaned the MAF thoroughly. It did seem a little dirty. Put it all back together later and and no more idling issue or SES light. I did notice that the fuel trims were fluctuating today where as yesterday they were at a solid 25% at idle.

I ask if it's time for a new MAF because I still feel the idle is a tad bit rough and I think I can hear small back fires in the exhaust still. The tach looks smooth and idles between 625-650rpm. The car has always seemed to idle a tad rougher than I had thought. Night quite as smooth as my fiancee's Lexus GS400, but maybe thats just how these cars are. It's definitely more sports car than luxury car.

Any input is greatly appreciated! !!!!

Specs on the car if anyone needs them are

2004 Coupe 6spd 134k miles bone stock to the paper airfilter

 

Maybe you have a loss of back pressure. Check your exhaust and that your intake is 100% secure.