Ok first off, I am checking issues and trying to narrow it down. I'm not just reposting the same thing every week like some of you may think by now.

Basic symptoms: stumbling on start up and heavy gas (hills/highway/etc), little to no power, rough cold starts

I just about narrowed it down to either a TPS or MAF. I threw out the idea of a bad MAF because there is absolutely no change running with it unplugged and it runs too terribly to think that the "fail safe" settings make it run as such.

I have a few new codes since my check a few weeks ago as well. The entire list is as follows:

p0733 - 3rd gear incorrect ratio
p0171 - bank 1 lean
p0174 - bank 2 lean
p1174
p1171
p1300
p0304 - cyl 4 misfire
p0302 - cyl 2 misfire
p0308 - cyl 8 misfire
p0306 - cyl 6 misfire

I'm really starting to think I just have a huuuuuuge vac leak somewhere. My intake plenum is only held on by the right 2 bolts because the left 2 are stripped (curse you cheap torque wrench!). At this point I think doing a valley pan gasket (leaking coolant behind anyways) and installing a new intake to fix the stripped bolts may fix it. If anyone has any inkling of an idea that may help that would be awesome too. I've chased this problem for months and as soon as I think I have it narrowed down something else pops up.

 

You should be able to test for a vacuum leap by spraying some starting fluid near the likely spots. If you make friends with another local D2 owner, you could try swapping a known good MAF in too. That way you can really eliminate it as the culprit. (There being absolutely no change just tells you it's either not the problem or it has totally failed and isn't even being recognized by the truck at all.)

Which bolts stripped? Depending upon the location you may be able to either helicoil, or look at tapping to be a very slightly larger size. (Disclaimer: I'm not sure exactly which ones you're referencing, so tapping the holes or inserting a helicoil may not work...just throwing these ideas out there as possible options...)

 

I think you know what's wrong already so I'm not sure why you've been chasing the problem for months.

1) 2 stripped bolts on the same side of the intake will for sure cause a vac leak. I think you could probably re-thread and use a larger bolt instead of a new intake.

2) All of the misfire codes are on the same side so I'm thinking maybe a bad coil on the side. You can try to switch the coil packs and if the code's jump the the other side then you know it's your problem.

3) Where exactly is it leaking in the rear? Are you sure it's the vally pan gasket and not the heads leaking? A common place for them to leak is in the rear above the starter.

 

I suppose it could be the heads but the PO did head gaskets including resurfacing so that "shouldn't" be the issue. The bolts that are stripped are the intake plenum bolts on the starter side of the engine (I believe that is the even side as well). The coil pack is a brand new one from AB, less than 3000 miles on it. The misfires are new, the issues have been happening for a while without misfires.

 

IF you unplug the MAF and there is absolutely no change -
then your MAF is bad.

Borrow one from a buddy and see if that fixes it.

Stripped bolts will give you a vacuum leak now - or later as the
manifold will work loose.

These bolts will need to go to torque specifications.
If they don't then FAIL - needs to be fixed.

 

I don't necessarily think the MAF is good or bad...basically the way I'm thinking is that if you took a perfectly working disco (those exist?) and unplugged the MAF....it wouldn't run as terrible as mine runs. If it is indeed broken...then there must be something else causing it to run the way it is running as well. I'm more interested in that problem right now.

 

I've read that a few times and it still doesn't make any sense.

Flip packs to be sure they're not the issue (free).
Fix stripped bolts (cheap)
Replace MAF (less cheap)
Head gasket job (leastest cheap)

shouldn't be a problem might have been a tip off that it will become one. (Don't know if you posted elsewhere, but did you get receipts for the job from PO or know which shop did the work?)

 

The PO did the HGs himself..I don't necessarily trust them but trying to rule out all other issues as its my only vehicle so don't really have the time to do them not to mention the means to get the heads to a shop for inspection/resurfacing. I have a new lower intake set to go in so if I still have the issue...and leaking behind the engine when the new VP gasket and intake go in then it'll be pretty much solid evidence that the HGs need to be redone. As far as my MAF description goes...as basic as I can explain it is this. Go out to your truck and unplug your MAF and take note how it runs. It will run poorer than it should....but it wont have the same symptoms mine has meaning there is more wrong with my truck right now than just a MAF.

 

we gotta see and hear it.

can you do a cell phone vid and put onto youtube?

then put youtube link onto here

 

Ask and you shall receive.

When it bogs down thats me pressing the gas slightly. You can hear a few backfires in there and probably see the reflection of me giving the finger to my UG for the stupid oil miles alert.