Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
How does the cam gear look? I've seen these shear off the keyway and let the cam gear rotate on the camshaft.
Do you have any trouble codes?
Do you have a scope that you could use to check the signal from the Cam sensor and crank sensor? It's possible that the crank sensor could be the problem as well.
Something has to have moved, the phaser, the reluctor ring, something.
So if you unplug the sensor and start it and then plug it back in while running does it stall out?
I would probably pull that cam phaser and replace it. I would also pull the starter and look into the crank sensor orifice and see if there is any obvious damage to the reluctor ring with a good bore scope.
I just found that also, but it doesn't say why it would need a new engine.
It just suggests checking for a powertrain warranty. What a bogus TSB.
I would pull the cam phaser and just take a look.
I would pull the cam out and see if something has gone wrong. I'm not sure if that van is one where they press the cam journals and lobes onto the cam shaft. If that's the case, you could have a cam journal or lobe that has somehow spun on the shaft. Chevy did that on a couple of year models, but the express doesn't specify whether it has pressed cams in the manuals.
No, I don't think it spun a bearing, Chevy had a couple of CAM shaft designs where they pressed the cam lobes to the cam. If they weren't manufactured correctly the lobes could spin, thereby changing the valve timing.
Yeah, that's the strange part. It would have at least a slight miss.
You are sure the cam sensor isn't faulty right?
Not sure what else to suggest from here. I think the best bet will be to check out that cam.
Sorry. Got pulled away here at the shop.
With all that you have done, I'm at a loss. I'll opt out and see if anyone else has any insights.
Here's a thought. Try plugging in the cmp and unplug the alternator. I was told by one of my local dealers a while back that a handful of these vans got wrong alternators in them. If I correctly recall they were causing things like misdiagnosed throttle bodies or something. It's kind of a shot in the dark but I want to follow along on this if you guys don't mind.
Now that it's somehow running...will your scan tool do a cam variation relearn?
I would probably replace the new cam sensor and then see if you can perform a cam variation relearn.
It just seems to me that it can't be working right if the engine won't run with it plugged in and you have already fully tested the PCM. Unless there is a short to ground somewhere between the cam sensor and the pcm...
Still nothing with a new sensor? I have all of my Technicians pondering this one and we all come up puzzled.
That sounds great.
Maybe an aftermarket alarm or remote start?
I'm showing green with black tracer to the instrument panel and central junction box. Red to to battery junction block but turns orange at connector #3001. And a Black battery cable. Assuming this is 2.0 engine. If equipped with a 2.5 let me know and I'll check again