Cranks but wont start, 93 DOHC

[AL]

Crank sensor signal is 973... Range is supposed to be between 800-1200... So it ohmed out correctly also... FML

[Imp558]

Do you know the PCM is good?

[AL]

I replaced it with another one I had... Same results

[AL]

BUMP

 

Is there anything else that I could be missing here? What tells the PCM to ground the injectors?

[Crazy K]

what PROM chip do you have in it?

[AL]

Whatever came in it... I havent touched it mainly cause I dont know anything about the chips

[Crazy K]

Whatever came in it... I havent touched it mainly cause I dont know anything about the chips

are you using an auto chip in a manual car? or is this chip from the manual?

[AL]

The wiring harness, PCM, and Fuse box are the same that I took out, I swapped them onto the new motor as I was told the harnesses are different... The engine I put in was originally mounted to an Auto trans so I put the harness from the manual trans car on and put it in... Hope that makes sense... Basically its the same harness as before, no changes

[Crazy K]

so it is the original manual prom chip? I saw a perfect 5 speed car in a yard. what was wrong with it? glass said fuel pump. it had the wrong PROM chip. car would not run. why I ask you.

[AL]

But it ran before I did the swap

[Crazy K]

But it ran before I did the swap

ran with the 5 speed?

[AL]

Yes

[Crazy K]

no clue. hmmm...

[White93z34]

I know this sounds dumb, but I still would not rule out a bad injector.

 

 

Just how good is your fuel pressure at the rail?

[ns87]

Subscribing to this. This is exactly why I had to get rid of my Cutlass Supreme. If you turn your car to the "on" position, does the check engine light come on?

[jman093]

I'd also suggest checking fuel pressure. Just because you got fuel to squirt out of the fuel rail doesn't mean you necessarily have the right pressure. People drag cars to us all the time at work and don't believe us when we tell them it has a fuel problem because they "got fuel out of the fuel rail."

 

Ohm testing the crank sensor is also not a way of completely knowing if it's working right, and doesn't check the crank sensor circuit at all. Does the tach register some RPM when cranking?

[AL]

I wasnt able to check exact fuel pressure but I will try to tomorrow...

 

The check engine light comes on when the key is turned to on... No codes found when scanning

 

It reads 264 rpms while cranking... Doesnt show on the tach but it does show up on the scanner under crank rpms

[AL]

Keep in mind, the car was running before I pulled the motor and I am using the same wiring harness as before.

[AL]

So I am thinking that there is a bad ground somewhere from the PCM... Does anyone know where the PCM sensor grounds are? I can get a wiring diagram to show what I am talking about... I thought most of the grounds were attached to the bellhousing bolts, then a ground below the y pipe/crossover, then a ground for the battery right next to the AC Accumulator I think, with a ground wire going back to the bellhousing... The headlights ground on the radiator support, is there any I am missing?

[ns87]

unfortunately every sensor grounds to the ecm as well. That's why I gave up

[AL]

True, but when I tested a couple of the grounds from the ECM, It would not light up the test light, which means they are not properly grounded

[AL]

Can anyone tell me if I am missing a ground location?

[White93z34]

FWIW I just found and ohmed out my bad injector, it read about 5-5.5 ohms. That was enough to make the car not run, and the injectors not pulse.

[jman093]

Here's a ground diagram for a 93 Lumina. Looking at the Vin X ECM, all 5 ground wires eventually ground at the transaxle stud, which is also a redundant ground with other engine bay grounds.

 

http://i90.photobucket.com/albums/k277/87aero/Ground1.gif[/img]

[AL]

Thanks, It looks like I have all my grounds... I will double check tho.