# 97 PU with an idle problem



## Broadwell (Mar 9, 2013)

I have a 97 nissan pickup with a 2.4 and a 5 speed (my first straight drive). i got the truck with 187k miles. first issue was the normal IAC sensor wires that fell off the sensor. i shelled out the $60 for a new one and the plug was missing so i twisted the 2 wires together with wire nuts. now a lil while later its got another problem. 
After the truck warms up and has been shut off and started up again (like getting gas) the truck dosnt wanna idle. if u put ur foot on the gas a little it will lope. rev it up and it spits black smoke (rich). it has been gettin worse over the past 2 weeks. ive cleared the codes and they came back. P0100 (MAF) mainly but also a O2 sensor bank 1 code. the MAF sensor is like $400 so i was wanderin if anyone could tell me possible causes. ive searched 3 junkyards with no success of this specific maf sensor. it has the 2 bolt maf and ive heard ther is a way to use a 240 maf sensor or something but dont know anything about it.
If i unplug the maf, the truck idles fine but wont rev up. Any information is helpful! Im used to working on chevy's and ford's


----------



## TheRepairMan (Jun 30, 2009)

So it ran and idled okay for a while after repairing the IAC and wiring?

If that MAF code continues to return you could try giving it a good cleaning. Any parts store should have a can of MAF cleaner on hand. It's well worth a try. Hopefully it doesn't have wiring troubles also. That's a little odd.

-R


----------



## Broadwell (Mar 9, 2013)

i took it to a local shop and they cleaned it and cleared the code. i got a maf off ebay but u know how some aftermarket things are. didnt work at all


----------



## smj999smj (Jan 1, 2006)

Are you sure you repaired the IAC and not the IAT, which is mounted to the underside of the air cleaner housing? You should also replace those wire nuts with insulated spade connectors.


----------



## Broadwell (Mar 9, 2013)

oh im sorry yeah it was the IAT. the one in the bottom of the air cleaner. and ill try that but im not sure thats where my problem. ive read on here and it looks like others have had the exact same problem. im thinkin its the maf


----------



## smj999smj (Jan 1, 2006)

Bad IAT won't give you that kind of symptom plus since you have the code for the MAF sensor, it's most likely that. There was a TSB on the IAT bracket which usually breaks, but since you don't have the harness connector for it, there's no sense in installing the updated bracket.


----------



## TheRepairMan (Jun 30, 2009)

smj999smj said:


> Bad IAT won't give you that kind of symptom plus since you have the code for the MAF sensor, it's most likely that. There was a TSB on the IAT bracket which usually breaks, but since you don't have the harness connector for it, there's no sense in installing the updated bracket.


I agree.

Before I bought my 94, the original owner had towed it to my shop in 08 with the very same symptoms. MAF code, wouldn't idle, surging badly off idle, and smelled real rich. I put a new MAF sensor on it, cleared the code, bought the truck from them shortly after, and it's been running great since then.

Somewhere on the net I've seen very detailed instructions on exactly how to test and properly diagnose a MAF sensor on our trucks. I'll research that again.

I replaced the 02 sensor on mine in 2011, but there was a light on and code stored for it, with no noticeable drivability problems at all that time.

-R


----------



## smj999smj (Jan 1, 2006)

My experience with testing MAS and MAFs is that if it fails the testing procedure, then you know it's bad, but if it passes the procedure, it may not necessarily be good! I've had many MAF sensors pass the service manual test only to find out when I swapped in a "good known part," the problem went away. So, take the results with a grain of salt, so to speak.


----------

