Topic: code po112

[76flh]

  a few weeks ago i installed a banks header on my 98 2.5. since then i have been getting the code po112 ( intake air temperature sensor voltage to low ) i put in a new sensor and cleared the code. it keeps getting this code and it pops up after i drive the 50 mile round trip to work. the wierd part is the light comes on when i go up my driveway. i have recheck all the sensors i unhooked while doing the header change. i have installed two ex manifolds on it before giving the banks header a try and did not have this trouble before. i have checked the voltage and it is getting the 5 volts from the pcm like the site for codes shows on how to check the iat sensor. last night after the code came on i plugged in the obd scanner and read the scanner and it showed water temp at 210 and the air temp was almost 300. the site said if the air temp is almost 300 the code will show up. does any body know why i am going thru this after putting the header on.

[sharpxmen]

i'd say relocate the sensor to the airbox. But first i would maybe give another sensor a shot, maybe it's busted right off the shelf, not unheard of.

[grumpygy]

How close to the header is the sensor.  Headers let out more heat than the old Mainifold would.

  I throw that code in my truck and it has Zero Changes to it.  But its only on a hot day and only after I make a short stop and go that requires a restart.

[sharpxmen]

How close to the header is the sensor.  Headers let out more heat than the old Mainifold would.

  I throw that code in my truck and it has Zero Changes to it.  But its only on a hot day and only after I make a short stop and go that requires a restart.

the sensor is on top of the intake manifold on the cyl 4 run (close to the firewall). that was kindof my thining too that he gets more heat but it still shouldn't throw a code for that, i would either try another one, relocate it or use some heatshield on the header (i wrapped my pacesetter and didn't have this issue so i can't tell if without the heat wrap would have had this issue).

[76flh]

when i left work yesterday i plugged my obdll scanner in and when i slowed down and turned up the driveway the intake air temp went up to 285 and the light came on.i took the sensor out so i can turn it in today and try another one. the heat was super hot when i open the hood. before i put the air box back together i took off the little air inlet that points up to the hood were the air comes in. so now it has a bigger air inlet before the filter. if the light still comes on after putting in another sensor i am going to relocate it to the air box above the throttle body and move the air intake closer to the grill and get a hood lover panel from hyline so the heat can get out. i am over with dealing with this. thanks for all the input and i will keep posting updates until this is fixed.

[VA_YJ]

I'm running the Banks header on my 2.5.  One thing they caution you about in the instructions is to make sure you have good fuel pressure.  Lean conditions can cause heat build-up and melt pistons.  Check your fuel pressure ASAP.

[76flh]

I'm running the Banks header on my 2.5.  One thing they caution you about in the instructions is to make sure you have good fuel pressure.  Lean conditions can cause heat build-up and melt pistons.  Check your fuel pressure ASAP.

  i will check about this just so i know  how much i have, thanks. yesterday when i left work i plugged in my scanner. as i was about to hit the driveway i looked at the screen and the iat temp was 165. it stayed that way all the way up and when i got to my parking spot and stopped and it went to 173 at idle with the ac still on. so, by me taking that little air intake off before the air filter box and now it getting more air has made that big of a temperature change. it was just as hot yesterday as it has been all week. i am not going to drive it to work today, got to get gravel in the dump truck. i did put the old sensor back in and i took the other one back and traded it in for another one. i am going to leave it like this so i can double check my temps a few times. i will keep posting my updates. thanks for the replys.

[sharpxmen]

  i will check about this just so i know  how much i have, thanks. yesterday when i left work i plugged in my scanner. as i was about to hit the driveway i looked at the screen and the iat temp was 165. it stayed that way all the way up and when i got to my parking spot and stopped and it went to 173 at idle with the ac still on. so, by me taking that little air intake off before the air filter box and now it getting more air has made that big of a temperature change. it was just as hot yesterday as it has been all week. i am not going to drive it to work today, got to get gravel in the dump truck. i did put the old sensor back in and i took the other one back and traded it in for another one. i am going to leave it like this so i can double check my temps a few times. i will keep posting my updates. thanks for the replys.

your other sensor was busted. and that little tube, unless you always drive at wot at 5000rpm all the time your whole premise is incorrect, the airflow is controlled by the throttle and dependent on rpm and for sure not enough to cause a 125F difference.

[76flh]

 if the new one i took out was busted, i put the old one back in that was throwing the code to start with and so far it is ok? maybe i need to put the part back in and take a road trip and see what the temp will be. i am going to keep this all updated and thanks for that info.

[95 Lowbuck]

I think your missing the problem here.
Jeep put that sensor there for a reason and the FI
is programmed for it in that position.
If it is moved to the air box, you computer will now think that the engine has
colder than normal air in the manifold and make adjustments.
I would go back to wrapping the header to make the code go away.

[sharpxmen]

it's a common mod, unless you get knock there's no harm in it. the new sensor sounds like it was busted so it sounds like is not needed anyway

[76flh]

 thanks for all the help on this. i have put the little air horn ( not sure what it is called ) back in and drove it in this heat and with it in the code comes back on and i have the heat soak trouble. so, i took it back off and drove it and the iat temp does not get any higher then 165 and it never has came back on and have not had any more trouble. all of this started after i put the header on. i searched all over the web and found a few that have had this with a 2.5 and a header.