CEL being stubborn

[Alec]

K, so I've been getting a CEL for the past few weeks and finally bought an OBD II reader. Pulled a P 112 code. My book says something about the air intake temp sensor voltage low. So I figured I'd replace the sensor. The old one was all gunked up, so I thought that would fix it. Well, the light's popped on twice since the swap. Tomorrow I'm gonna inspect that sensor's wiring, but I was wondering if anyone had any ideas.

I'm glad I have the reader though so I can clear the codes and not have the bright orange light in my face all the time.

 

[Jason_25]

Hmm I think you may just have gotten a defective sensor.

If you don't mind, how much did the sensor cost you and where did you get it?

 

[BadAzzexplr]

Alec, I am having the same problem, I replaced the sensor and still receive the same code as you. Did you every find a souluiton?

 

[Alec]

Badazz, sent you an email.

But for everyone else, the code pops up a lot less with a new TPS. When it does pop up I clear it with my scanner; though I do have a handy piece of electrical tape to cover the light up when I don't have my scanner with me

 

[dartman]

just a little tip--when the cel comes on its for a reason--just removing the code is ok but there is a reason it came on.as for air intake code coming on--possibly cat. convertor may be starting to plug up although i think u would start to notice a low power problem.as convertor starts to plug hot exhaust is pressurized and backs up into the intake causing the temp. sensor to signal the computer.

 

[Alec]

The cat was replaced a few months ago along with the rest of the exhaust from the headers back. my truck throws codes often due to the amount of tuning that I've done to it. It's not stock by any means! When you do as much to a vehicle as I have, you're gonna have some gremlins.

I've replaced the IAT sensor once and cleaned it numerous times. I've checked all wire connections associated with it. I've also inpected (taken apart) the entire intake system through the TB. I believe the problem is associated with high intake velocities created under boost and/or the TPS wire harness, which has multiple taps both for the nitrous and the s/c. Believe me, I'd know if there was a problem.

 

[Robert]

I can't imagine a plugged catalytic converter causing the IAT to set off the CEL. The range for the IAT is much higher than your rubber intake hose can withstand. When I'm ideling hear in Phoenix in the summer with my open air intake, my IAT has climbed to close to 200F. If your engine is running, it is sucking air into the intake which will prevent any heat from a plugged converter working its way up to the IAT. Your engine is basically an air pump. It is only going to pump the air one direction unless you are backfiring. A plugged converter will make your exhaust hotter from the converter to the tail pipe, but not the other direction.

 

[Ray Lobato]

Alec,
The next time your CEL comes and you don't have your scanner with you, just cycle the ingition on and off 4 times. That will reset your light.

 

[Alec]

Thanks Ray, I use the tape when I'm on the road and don't feel like stopping.

 

[Jason_25]

Originally posted by Ray Lobato
Alec,
The next time your CEL comes and you don't have your scanner with you, just cycle the ingition on and off 4 times. That will reset your light.

Does this work with OBD I?

 

[Ray Lobato]

Jason-25,
I don't know, but you can try it and see. I found this out in Moab, when Geralds truck had a light go on. Wade (Go Offroad) said this was a ancient Chinese secret. Wade just happens to be a Ford Mechanic.

 

[Robert]

Originally posted by Ray Lobato
Alec,
The next time your CEL comes and you don't have your scanner with you, just cycle the ingition on and off 4 times. That will reset your light.

That method will only work on certain codes and only if the code has cleared itself. It doesn't work to clear a P0455, I went and tried it at lunch. Also a few years ago I got a CEL when I was driving across the US. I don't know what set the code off, but I sat in a rest stop turning my Explorer on and off close to 50 times before giving up. The next day I was so tired of looking at the light I disconnected the battery at another rest stop and didn't see the light for a couple more years.