i will be cleaning my tb tomorrow. i have been getting poor mpg and rough idle. should i clean iac or replace with bwd brand? i can only do this once right now.

suggestions?

 

Suggestions:

1. Punctuation is your friend.
2. Clean and test IAC to make sure it is good.
3. Replace IAC if it is not good per testing referenced above.


What does "I can only do this once right now mean?" Cost, time issue? I don't encourage anyone to just swap in new parts, as this is one of the most expesnive and ineffective ways of troubleshooting.

If time is the issue, it takes removal to test, and then getting new part if it fails. Obviously, testing costs nothing....

 

Remove the negative battery cable before cleaning or replacing the IAC please.

 

+1. If the old one was bad, and your PCM learned to compensate for this, the engine will behave strangely or not run at all with the new. Disconnecting the battery cable resets the PCM (computer) to factory defaults, and it will learn the new IAC.

 

i would also say clean it. only replace it if it is bad. the aftermarket ones seem to fail more often then stock ones. i think Wombat Ranger has replaced 2 or 3 of those cheap aftermarket IAC sensors under warranty.

 

IAC won't cause rough idle. it will cause either no idle, low rpm idle, or high rpm idle.
if you have one of these problems AND the pintle is gunked up, try cleaning the pintle and the well, and the hole at the bottom of the well.

if you have one of those problems and its not visibly gunked up, replace it.

otherwise, clean it of gunk by spraying it with brake cleaner, and look for other problems. for rough idle, check/replace plugs, dist cap, rotor, maybe wires.