Check engine light

[FFutch]

Hey all,I got on it pretty hard yesterday with the P. E. turned up to level 3 and the check engine light came on. I got home and hooked up the snap-on scanner up. It logged a M. A. F. sensor code input voltage low. I cleared it out (wasn't an active code)and everything is fine. Is it possible I overboosted,bad sensor,or what? The light hasn't came back on and the truck runs fine. I've also read on here about one sensor that gets dirty and causes problems,I. A. T. ???I think. Any other ideas?Any help appreciated. Doug

 

[Alan Reagan]

Almost any time there is a hiccup in a box the error shows up as a MAP over or undervoltage. Everything should be OK. Just keep an eye on the box. If you really overboosted, then you should have also had an error code for that.

 

[FFutch]

Thanks Alan,It's been 2 days and no light,so I guess all's well. Doug

 

[tgbol]

This morning as I got on to the freeway I hit the loud pedal and the check engine light came on. Codes 1693 and 1291. Worried about it all day until I got back to the yard. We hooked it up to the scan tool got a "undefined code set". Cleared the codes everything seems to be fine.

 

[Big White Beast]

And the answer is..........

1291 = No temp rise seen from intake heaters.



Energized heated air intake does not change intake air temperature sensor an acceptable amount.



1291(M) = Same symptoms



Problem detected in intake manifold air heating system



Straight from DC's manual,



Garrett

 

[tgbol]

Garret

Thanks!!! I was in kind of a hurry that morning. On my way to a Civil Service Oral Exam and an hour of traffic ahead me. I probably didn"t wait for the heater cycle. And has been colder than usual here lately.

Thanx again, Tom