My 1998 Dakota idles rough once it is warmed up and the exhaust smells rich but runs fine once I accelerate. Was leaning towards the MAP sensor but it tests out to be OK. ANy ideas what to look at next?

 

PS it has the 2.5L engine. Thanks

 

Swap the map sensor, they degrade over time and even though it provides a voltage, it may not be working correctly.

 

OK. I'll swap it out and see if it helps my problem. Thanks

 

So I found them on internet for $15-20. Local auto stores want $80-100. Are the internet ones that bad?

 

I swapped mine on the 4.7 with a Standard Motor Products one from RockAuto.com and so far no issues. It was something like $25 (as were all the ones I swapped, all of them are SMP sensors)

You could also try cleaning it with electronic components cleaner while you wait for the new one.

 

OK. Thanks for the info and quick response.

 

Or get a oem one off another truck like it an try it. Dont use off brand sensors - these trucks hate em .
Clean up the IAC also [ idle air control] .An last resort 02 sensors since they monitor rich/lean ..
Scanner can help pinpoint it too.

 

I replaced the power steering pressure switch and there doesn’t seem to be any oil leaking through the old or new switch. Still throws the p0551 code. The power steering pump does have a slight whine or squeal to it. Could it be that my pump is going bad?

 

I actually have 4 codes now. P0138,P0551,P0145, & P0141. I have looked these codes up. Is there a possibility these codes are all related?