Lumina Wont Start

[Goofy3392]

Alright, this is my first post on these forums. In our school shop we have this 1993 or 1992 Lumina 3.1L V6 that cranks but wont start. I guess the story is that these people were driving down the road and the car just quit and wouldnt start. So since then its been sitting outside in wisconsin for 3 months and hasnt started since. So its been in our school shop for about 3 weeks now and we cant figure out the problem.
We checked the fuel filter and thats good. Checked fuel pressure and it was 42? Sparking on all cylinders. We are trying to find the Camshaft/sensor but not sure where it is, we ran a scan tool on it and its a geneysis? and one time we ran it and 3 errors came up and now nothing comes up. When it sits over the weekend and we come back and we try to start it, it backfires or pops and the engine smokes on the side of the belt. maybe there is water in the gas? oh and it smells like there is gas in the oil. We pounded on the gas tank while cranking it and nothing happened. Any Suggestions? Thank You

[maxwedge]

Welcome to AF, are you a student? If so where is your instructor in this process?

[Goofy3392]

Yes I am a student, my instructor is around but he's always running around helping out the other students who dont know crap about cars. And I just want to know what you guys think so I can tell him. But he is pretty much clueless.
I forgot also, the car has had the "brain Box" replaced once already. My instructor thinks thats the problem but just wondering what you guys think..

[maxwedge]

I'd like to talk to your instructor, your terminology is incorrect as well as the diagnostic procedures, what is he doing to help you with this issue? We cannot replace his function on this forum. To see if this is fuel related spray carb cleaner into the intake and see if it fires. (PCM not brain box!)

[kevinb70]

well concerning the crank sensor...


i have a later model 3.1 (may not apply to your model), but one CKP is behind the crank dampener, the other is on the side of the engine (firewall side) just above the oil pan. Two crank position sensors i dont think there is a camshaft pos sensor...

if you are lying under the car, you can get to it by the opening between the side of the engine and the firewall, its somewhere below your exhaust manifold and above the oil pan line. Flat black plastic, with an offset hole that the bolt goes thru to hold it down. When you pull it out it's like a long plastic cylinder. You will be feeling for a something with a wire lead coming out of it.

check the lead running up, over the exhaust manifold and going into your wiring harness running near the throttle body. wires might have got melted and fused together. Might not be able to see the entire length of the wire easily.




if its sparking, I dont think it would be the crank sensor. (not too sure about that)


try the starting fluid / carb spray down the throttle body technique.

are the injectors getting any pulses? are the actually opening and delivering fuel?




if this is a auto mechanics class, a more orderly approach should be used like a troubleshooting chart.

[richtazz]

They didn't put a cam sensor in a 3.1 until the VIN-M designation in 94, so you're looking for something that doesn't exist on this car. I can understand that your instructor may not know the specifics of every car/engine out there, but he should have information available for you to reference. You said you ran a scan tool on it, what did it show? any codes stored? You gotta help us help you, or we could speculate for days.

[Goofy3392]

We ran the Scan Tool and nothing comes up now, but it does show an injector pulse width of .33m/s. The scan tool says its in open loop. I havent tried carb cleaner in the intake yet but I'll mention it on monday.