OBD1 M52 will not stay running

[Roysneon]

I resisted posting up for help but I'm stuck and getting really frustrated.

Went from an m50 and had to throw in an m52 for...reasons.

Got the thing running no problems for a while, then it randomly died. Now it starts no longer problem but dies immediately.

It's NOT a vacuum leak. There was one icv hose that was suspect but it was replaced. ICV was replaced with a known good one.

I am so fucking lost on what could cause it to fire up and run for a second then shut right down.

[hooken m]

the ICV hose that you speak of, is the the curved one that leads to the manifold? on my swap i had a similar issue and found that the curved hose popped off.

[dirtbag30]

it could be anything. is it getting fuel?

[Roysneon]

Definately checked both ICV hoses, they're leak free.

Verified that it has fuel, fuel pump primes and it holds pressure.

[franky2fingaz]

Now it starts no longer problem but dies immediately.

.

does it run good then cuts out or sputters the whole time?

any codes?

[Roysneon]

Kinda kicks and sputters before starting sometimes (but not always) and then starts up great, then promptly fucks off.

[Roysneon]

I do have access to a code scanner but haven't used it yet...durp

[mikegar]

I had a similar issue. The alternator was fuct. Check all your electrical connections and take the alternator to get tested.

[Roysneon]

Got the codes from the Peake, got a code for every ign. coil and 1A for Control Unit Power Supply.

So yeah, could be the voltage regulator or DME relay. I'll have to change out the alt. with a spare I have and try the relays.

[Roysneon]

Changed alternator, changed DME relay with known good, tested units, still nada.

I think my next move is going to be retrace every bit of wiring and/or just send off the OBD 2 harness to be re pinned and OBD2 DME flashed by Markert and have everything done properly.

[iViLe]

It is not the fuel pump turning off once it starts, as in a dodgy relay?
Try unplugging the maf sensor and see if it starts which it should and try unplugging the oxygen sensor.

[e30austin]

Cps...............

[hilux30]

FPR holding vacuum? cheap check

[Roysneon]

So it's finally been warm enough here and there for me to play around with this thing and I found a couple issues that I fixed

1. Two coils had the wrong wires plugged in
2. FPR vac. hose was off the intake manifold nipple.

I assumed my battery was toast, so I got a new one. Car still cranks way too slow to start. I'm going to go over the leads from the battery to the starter. I have a single wire going from the positive terminal to the starter main stud and one going from the main stud to the alternator. That sound right?

[Roysneon]

So I fixed up those problems, and finally had a day off to work on it in daylight.

The slow crank was because the damn serpentine belt was off the power steering pully and was fighting against the motor. So then it turned over nicely. The thing still wouldn't start and stay running though.

Then while cranking it over, it puked up a bunch of oil out of the dipstick hole in the pan. I still didn't have the proper hold down bracket for it so it was just kinda chillin there. Once I got it at least shoved down in and there was some sealing of the pan the thing started and ran quite well.

Now my question is: why the fuck was there that much pressure in the crankcase to force oil out of that little hole? I'm going to borrow a compression tester as blow by was suggested to me and that seems to make sense. Ugh I just really want to drive this thing. I don't want to have to swap it again right now.