GM3400 - crank sensor is loose!

I have a 92 Chevy Lumina APV van with the 3400 thats is giving me trouble.

The van died on me out of town, and the shop I found, as part of their diagnostics, replaced the crankshaft sensor. It didn't help, so they put the old one back in. The problem ended up being something with the ignition, the part thats under the coils I think.

Anyway as soon as I left their shop, I noticed a very slight ticking that I had never heard before. I had the mechanic come out and listen to it, and of course he thought I was crazy that I could hear some "ticking" over a noisy 150K mile GM engine.

That was about 6 months ago. Recently the noise has gotten louder and once in a while the engine would "hicup" or hesitate for just a second. Now it will sometimes stall, and not always run right away again. I thought it was the timing chain but listening/looking at it again tonight I see the plug that plugs into the crank sensor - and its just bouncing all over the place! I think the sensor is just

So the shop must have not adjusted the sensor correctly when reinstalling. I'm hoping someone here has experience with the crankshaft sensor and can tell me - can it just vibrate loose, or do you think its been pushed completely out of its socket, ruining the threads on the block? Do you think the sensor is probably ruined?

I know, its hard to guess without taking it all apart, but maybe someone that knows what this sensor is like and how its mounted might have an idea. Its probably going to cost me $100+ just to have it looked at, then a few hundred more if I have the sensor replaced... so I'm debating just junking the van, its 16 years old now.

-thanks

Reply to
zirconx9
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wrote

According to Rockauto, this is what your sensor looks like:

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Seems like it just sits in a hole, with a small bolt going through the metal tab at the top to hold it in place. If the bolt is missing, the sensor can wiggle around, confusing the computer. Of course, if the bolt is still there, and it's the plug or the sensor that's broken and flopping around, then it's new parts time. If you can easily reach it, you shouldn't have any trouble replacing either the bolt or the sensor yourself.

Reply to
MasterBlaster

Thanks for the pic. I'm hoping the "ticking" just vibrated the bolt loose, and thats all it needs. I think the harmonic balancer needs to be removed to get to the bolt, so I'll still need to take it to the shop. I talked to them this morning and they said its just over an hour labor to remove/install the sensor, so thats not too bad. I just hope it didn't damage anything inside the engine.

Reply to
zirconx9

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