Rough idle? P0171, P0174? Here's what you need to check first!!!

[lynn]

I was all worried and stressed trying to figure out what was wrong and trying all your sugestions and I just needed to go back to the basics. I had a clogged fuel filter runs great now.

 

[flagger]

Maf?

Sorry to be a klutz but what is an MAF and how do I clean it? Search function returned nothing.

 

[Lane24]

It's the Mass Air Flow sensor. It's located in the air inlet tube that comes from where your air cleaner/filter is. Just disconnect your air inlet tube ahead of the sensor, and spray some MAF cleaner through the screen at the little elements in the center of the sensor. Let it sit for 5 minutes or so...,give it another shot, let it sit for another 5 minutes, then start your engine. Some people just use electronics cleaner, but I recommend actual MAF cleaner from the auto parts store. You can also take the sensor right out and clean it that way too, but it's easiest to just spray it where it is. You can hold a rag or something behind it. Here's a pic of what you are looking for. Mine looks a little different on my engine, but it's pretty much the same idea.

 

[flagger]

Thanks for the help!

 

[dano]

mee too

Well, after reading all these posts on the PCV elbow, I'm gonna have to go out and check mine. My 05 Expy has 108K miles on it. Its got a little roughness to the idle. My wife says it doesn't sound right to her...but what does she know, anyway? (although I'm about 50% deaf in right ear and can't hear in the other), so maybe she is hearing something I can't.
Something else, if I was to buy a computer for reading codes and diagnostics, what is a good inexpensive one to buy? I see all these codes you guys have had on your expys, are these something that are there but don't show up til you put them on a diagnostic computer?
Just wondering,
dano

 

[Lane24]

I just went to the Value Auto Parts store when my CEL came on, and they read it for free.

 

[michaelinchains]

great post,wish id seen it sooner-just dropped mine off at the shop for this exact problem.

 

[ELVATO]

If you have a Harbor Freight near by, they usually have cheap OBD II scanners.

 

[BadCompanyRods]

Not to beat a dead horse.. but also check your TBs if they have a black ring around the inside of the TB that can cause rough idle and even some hesitation on extreme cases.. Get some TB cleaner and clean that up too..

 

[strokin393]

Mine starts up idles high for a second then real low then it shuts off. I can't keep it running and won't take the gas when I try to give it gas. What could this be?