Is it the Fuel Pump? (Just drove her, no parts necessary!)
Strangely enough, the balancer bolt seems to be different sizes on different cars. I know for a fact it is 24mm on my 90 VIn C engine, but I've heard of it being 28 on other cars... so its going to be a hit and miss.
http://lesabret.com/phpBB/viewtopic.php?t=3404 <--- Flip through that and you'll know what I mean...
http://lesabret.com/phpBB/viewtopic.php?t=3404 <--- Flip through that and you'll know what I mean...
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Posts like a Camaro
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From: Jenison, MI (Near Grand Rapids)

Oh yeah, I do seem to recall another thread on here too, saying that the bolts were sized somewhat randomly.
I went to Sears today to look for a 28mm impact socket. They don't sell them! Sears! What the heck gives?!
So I guess I'll have to go try the local SK dealer tomorrow...
I went to Sears today to look for a 28mm impact socket. They don't sell them! Sears! What the heck gives?!
So I guess I'll have to go try the local SK dealer tomorrow...
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From: Jenison, MI (Near Grand Rapids)

Well, I was all set to swap in a new crank sensor today, but I hesitated as I sat there in the driveway with the wheel off and the impact ready. It just didn't seem right.
So, I decided to try one more diagnostic idea that popped in my head. I pulled the plug for the crank sensor, turned on the key, and tested for the 10v sensor power. And, I got 3-4v from sensor power to sensor ground. Woah. That'* not good. The power to vehicle ground was good, about 10-11v. So it was a problem with the sensor ground.
Then I thought maybe it was the harness was bad, so I probed some wires up by the ICM, and got the same result.
Back to the Haynes wire diagrams I went, trying to figure out what the heck was wrong. The diagrams don't really say how the sensor ground is produced in the ICM (whether it'* just a re-labeled vehicle ground, or comes from the ECM, etc.) It does show a couple of black wires coming off of the ICM, one being to the ECM, the other going to ground. I probed the one that existed, and it was either a bad ground or the ECM.
Somewhere in here, I also unplugged the cam sensor, since that also draws power from the same leads as the crank sensor. There was no change though.
Back in the diagrams though, I see that there'* another ground, just a vehicle-contact ground, apparently where the ICM contacts the bracket. Whipping out the multimeter again, I probed for voltage between the positive battery terminal and the metal base plate of the ICM and got... nothing.
Ah ha!
I can't imagine how two metal plates can sit next to each other, held together with 6 tight screws and not make electrical contact even despite some corrosion, but that'* exactly what was going on. I cleaned both surfaces with some emery cloth, sandwiched some steel wool between the two for good measure, put everything back together, cranked her, and she fired. A couple fires later, she was started!
Not for too long though, since I had plug wires against manifolds, and really wanted to get my fuel pressure gauge on there to see where that part of the situation was at.
Once I got everything re-routed and heat-shielded, and the gauge in place, I fired her up again. We have about 25 psi of fuel. Not so good. But that'* better than I thought. Key-on only, I get about 20. So, now we all know that a Vin C will run (albeit not great) on 25 psi of fuel.
I pulled the gauge off, closed the hood, and took her around the block (up to 55 mph). She drove okay... the fuel is definitely an issue yet. Still... she'* ALIVE!
And that'* a definite plus for the resale value.
So the big thing that I want to communicate here, is that if you ever have an ignition problem that you just can't find, clean the surfaces of the ICM and it'* bracket! Such a stupid little problem, but I had half the car apart trying to find it, and nearly installed a $30 part which would have done me no good.
Thanks to all who threw suggestions my way! It really could have been any of those things...
So, I decided to try one more diagnostic idea that popped in my head. I pulled the plug for the crank sensor, turned on the key, and tested for the 10v sensor power. And, I got 3-4v from sensor power to sensor ground. Woah. That'* not good. The power to vehicle ground was good, about 10-11v. So it was a problem with the sensor ground.
Then I thought maybe it was the harness was bad, so I probed some wires up by the ICM, and got the same result.
Back to the Haynes wire diagrams I went, trying to figure out what the heck was wrong. The diagrams don't really say how the sensor ground is produced in the ICM (whether it'* just a re-labeled vehicle ground, or comes from the ECM, etc.) It does show a couple of black wires coming off of the ICM, one being to the ECM, the other going to ground. I probed the one that existed, and it was either a bad ground or the ECM.
Somewhere in here, I also unplugged the cam sensor, since that also draws power from the same leads as the crank sensor. There was no change though.
Back in the diagrams though, I see that there'* another ground, just a vehicle-contact ground, apparently where the ICM contacts the bracket. Whipping out the multimeter again, I probed for voltage between the positive battery terminal and the metal base plate of the ICM and got... nothing.
Ah ha!
I can't imagine how two metal plates can sit next to each other, held together with 6 tight screws and not make electrical contact even despite some corrosion, but that'* exactly what was going on. I cleaned both surfaces with some emery cloth, sandwiched some steel wool between the two for good measure, put everything back together, cranked her, and she fired. A couple fires later, she was started!
Not for too long though, since I had plug wires against manifolds, and really wanted to get my fuel pressure gauge on there to see where that part of the situation was at.
Once I got everything re-routed and heat-shielded, and the gauge in place, I fired her up again. We have about 25 psi of fuel. Not so good. But that'* better than I thought. Key-on only, I get about 20. So, now we all know that a Vin C will run (albeit not great) on 25 psi of fuel.
I pulled the gauge off, closed the hood, and took her around the block (up to 55 mph). She drove okay... the fuel is definitely an issue yet. Still... she'* ALIVE!

And that'* a definite plus for the resale value.
So the big thing that I want to communicate here, is that if you ever have an ignition problem that you just can't find, clean the surfaces of the ICM and it'* bracket! Such a stupid little problem, but I had half the car apart trying to find it, and nearly installed a $30 part which would have done me no good.
Thanks to all who threw suggestions my way! It really could have been any of those things...
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From: Jenison, MI (Near Grand Rapids)

Originally Posted by crzydmnd72
Jon, thats some might good digging!
I woulda lost patience, threw the crank sensor in there and been really Ticked! when it didnt fix.
Why sell now? keep driving
I woulda lost patience, threw the crank sensor in there and been really Ticked! when it didnt fix.
Why sell now? keep driving

Why sell? Well, even with the spark back in play, it still has lousy fuel pressure, and takes some patience and skill to start. Once running it gets around okay, but it will hesitate if push it. I'll have to pick and choose my holes in traffic. Still, you will say, why sell? Put in a fuel pump and drive into the sunset! I would, gladly, but as I was digging into the depths of the car, and crawling beneath it, I saw just how bad it'* rusting away. It won't be too long before it'* unsafe, in my opinion. I've already thought that if I ever got in an accident with her, I'd probably die. With a family now, that'* a bad thought. And I've heard of the subframe simply dropping out of these things when they get too rusty. That would be bad, too. No, better to sell now, while it'* still running (mostly) and worth something, rather than waiting until it either folds in half, or kills me, or both.
So while I always said I'd drive this thing into the ground, my definition of "the ground" has changed to include where it'* at now. The end is near.
Besides, I already have a '93 SSE lined up, if only the seller can come up with a title and get over the plague that he seemingly has at the moment. And that one is seemingly rust-free.
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