Help! Car has been dead far too long!
The car ran like a champ, no problems at all one night in February. I got in it to go home the next morning and it would not start. It cranked over just fine, but would not start. I checked at the schrader valve and found there to be no fuel pressure with the key on. At this point I was thinking the fuel pump may have gone out. I decided to dig a little more, so I pulled a plug wire and stuck a screwdriver in it and set it close to a good ground, turned the key, and no spark either. So I had no fuel and no spark. I went through and checked all the fuses and they all looked good. I had a problem about 2 years ago where my VATS decided to quit working and wouldn't allow the car to start so I thought that may be the problem again. I sent my PCM to LG Motorsports (where it was dyno tuned originally) and they disabled the VATS in my PCM then they tested it on 3 cars and it started all 3 cars right up no problem. In fact they also returned to me a second PCM to try should mine not work that they also tested on all 3 cars and it too started all 3 of those cars. I tried both PCM's in my car tonight and neither one would start my car. Again I checked the schrader valve and no fuel, checked the plugwire again and again no spark. I don't understand what I may be missing here. I know the PCM is good, and as far as I can tell all my fuses are ok, yet I still have no fuel or spark. Any help as to what this problem may be is greatly appreciated as I am at the end of my wits with this one. I have considered trying to track down the VATS computer (I think it may be on the passenger side under the dash?) and unplug it completely to see if that works.
Truly Frustrated,
Mike
Your PCM wiring harness is clean/not corroded?
You've checked all the fuses? (PCM Bat , PCM Ign and while you're at it everything else)
Does the starter kick in? the motor cranks but no spark or fuel right?
I'd start w/fuses ... if it worked one day and not the next and there were no changes done ... it's gotta be something simple I'd hope... so first make sure power is going where it needs to (fuses) , and make sure the harness that attaches to the PCM is clean...
Other than that I'm stumped...
Also I don't believe disconnecting the VATS (BCM) under the dash will fix your problem... it's already been turned off in the PCM ... and I believe even if it's security related you should get spark... just no fuel... (however I could be mistaken here)
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Mike
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Your PCM wiring harness is clean/not corroded?
Thanks again,
Mike
), I can't say off the top of my head the exact testing procedure but...It's just a reluctor/magnet setup. So at the very least you could check for continuity. Did you do the cam install yourself? Did this happen soon after the cam install by any chance?
Dheck,
I live just southeast of lafayette. I would be willing to pay your expenses if you would not mind coming up and scanning the car for me. At least then I would have some idea of what is going on with it. I am first going to try replacing the BCM to see if that helps. I plan on doing that by no later then Friday. If that does not work I'll let you know and maybe it would be possible to get together one evening or on a weekend. I would really appreciate the help.
Mike
1) PCM
2) BCM
3) Fuel Pump
4) Fuses
5) Fuel Pump Relay
6) Harness Wiring
7) Ignition relay
Beyond that I can only assume that my problem lies in the hands of a sensor or a switch. I have no idea which one. I have been tod about the crankshaft or camshaft sensors, but neither of those would explain why it will not prime the fuel pump. Or at least it doesn't make sense to me. I am getting pretty frustrated, so I am going to go pick up my tools and go to bed defeated yet again. Damned Car.
Last edited by RutanZ28; May 21, 2004 at 09:04 AM.
Bad key? I've seen ignition keys sometimes create problems...have a spare?
The power source to the fuel pump relay is hot. The trigger does nothing when you turn the key on so evidently it's getting nothing from the PCM. Now the question is why? What criteria have to be met for the PCM to send a signal to the fuel pump relay? Only thing I can think at this point is maybe that the fuel pressure switch is stuck which is telling the PCM that it doesn't NEED any more fuel so it doesn't turn the pump on when I turn the key to on. Then again there could be a lot of switches/sensors that would keep the PCM from sending that signal that I don't know about. I am still getting no spark when I crank the motor over. Could this be because it has no fuel and therefore sees no need for spark? I don't know! I am baffled by this. I hate to keep throwing parts at it. I simply need a tech II or autotap os some sort of scanner that can at least point me in the right direction. I'm stumped.
The power source to the fuel pump relay is hot. The trigger does nothing when you turn the key on so evidently it's getting nothing from the PCM. Now the question is why? What criteria have to be met for the PCM to send a signal to the fuel pump relay? Only thing I can think at this point is maybe that the fuel pressure switch is stuck which is telling the PCM that it doesn't NEED any more fuel so it doesn't turn the pump on when I turn the key to on. Then again there could be a lot of switches/sensors that would keep the PCM from sending that signal that I don't know about. I am still getting no spark when I crank the motor over. Could this be because it has no fuel and therefore sees no need for spark? I don't know! I am baffled by this. I hate to keep throwing parts at it. I simply need a tech II or autotap os some sort of scanner that can at least point me in the right direction. I'm stumped.
Is something shorting out your PCM's? Getting power at the PCM?
there is no fuel pressure switch, you have no spark because that is triggered by the same thing as the fuel pump.


