Group

well i posted about my truck(97 4x4 auto psd) hiccuping while driving and i thought it was a cam sensor, Well i just borrowed a buddies Actron Scanner, and went to see if there were codes. it says no codes all pass.
I then went to the next item which is check MIL status ,
it says with the truck running when i hit go it should turn on the check engine
light, MINE DOESNT come on!
Other weird thing is since i've owned this truck the MIL on lites for a millesecond and then goes out.just enough to see that it was lit then out. is this normal?
I then went to the 3rd option to check for codes while engine is running
and the old PSD went nuts, started to run like crap, buck the wait to start lite came on, and i quickly shut her down!

Now to conclude, other then the occasional hiccup, the truck runs great
Has ton of *****, doesnt blow smoke..
But the hiccup and now the no MIL function has me wondering if i have a computer going out??

I also see theres a computer and a another box on the inner fender
for the injector control module.
I'm assuming i would change the one inside the cab?
Would love to hear from you guys

 

The one inside the cab, behind the Emergency brake, is the pcm, and that's the one you'd need to change, if it comes to that. Since you've already checked for codes, why don't you try pulling the fuse in the box on the driver's fender that controls the pcm. It will reset it, and clear any codes, even if they don't show up on a scanner. The fuse you'd want is the 9th one up from the bottom in the left row. It's commonly referred to as the "#9 fuse". It's a 20 amp maxi-fuse, and is easily identified because it has 30 amp maxi-fuses on either side of it.
If you're patient, you can pull the fuse for 20-30 minutes, and then reinstall it. If you're impatient, you can merely disconnect both batteries, and turn on your headlights to drain any residual power from the system. Once you've turned your headlights on and off, you can reconnect the batteries. Either process will reset the pcm, and could make all the difference for you.
I've had some wierd things happen with my truck, that defied diagnosis, but pulling #9 corrected them.
I hope this helps.