Why does the check engine light not stay on once it comes on? When it comes on, if I shut the truck off for a minute or so, the CEL may not come back on for a week or so. Is this normal? I know what codes it's throwing (12, 32 & 37), it just seems weird that the CEL doesn't come back on as soon as I restart the truck. Thanks.

 

Have you replaced the two o2's yet? They could be on their way out but not yet bad..As for the cam sensor I'd test it first then consider the timing belt replacement

 

No I haven't done anything yet pertaining to the codes, but will replace the O2's as you suggest. I have one new O2 from when I purchased the Hughes plenum kit. I just haven't done that yet. But any thoughts on my original question re: why the CEL doesn't just stay on (regardless of whatever codes it may be throwing)? Seems like other vehicles I've owned once it comes on, it's on until you fix whatever it is and clear the codes. Thanks

 

I suspect the codes you stated might be the cause of the intermittent CEL. The o2's not communication right then correctly with the PCM could be the cause..like I was saying they might not be working properly but just not bad yet. I see, did you do the plenum yet? typically the next fix following that repair is the o2's as well as the cat..and depending on the case the pass side cyl head too Ideal is in that order..