1997 Chevy 8 cyl 350 ticking and missing

[scott2020]

https://www.youtube.com/watch?v=YomdfOl_TOc

 

My 1997 Chevy truck started missing a lot, and I hear this ticking sound now.  It is worse with the AC on.  I was lucky to get it home.  Before I bring it to the shop, I was wondering if this was a major problem that is going to get expensive.  I have a feeling it is.  As you can probably tell, I'm not much of a mechanic.  I appreciate any help!

 

[Jsdirt]

Time to yank that driver's side valve cover and see what's happening in there. Could be a broken valve spring, or rocker stud, or the threads pulled off the stud causing huge clearance, or any number of other things.

 

How many miles on her?

[scott2020]

It has 212k on it, but I also found out the previous owner had replaced the head about 3000 miles ago on that side.  It wasn't done at a shop... so maybe something broke loose or something.

 

Sounds like it could get expensive.  Do you think it would be 4, 8, 12, or more hour job?

 

Thank you again!

[Doug_Scott]

You may want to check it at night with no lights on and check to see if you can see a bad plug wire. To me that sound is too steady to be something mechanical.   That being said, take the oil fill cap off the drivers rocker cover, stick your index finger in and see if you can change the noise with the engine running.  Your truck should be 10 years to young in order to have suffered from "chocolate camshaft".  It would usually hit cylinder 5 or 7, the oil fill cap resided  right between cyl 5 and 7 intake valves.  Pull both covers if you can't see the issue under drivers side rocker cover.  You will know if there is an issue, one or two rocker arms will have more "play" in it compared to most of the others. 

[riverbanks]

Yep,that's bad plug wires

[scott2020]

Thanks for all of the replies.  I have some good plug wires from a Vortec 8100.  Could I try replacing 1 with that as a test?

[Jsdirt]

59 minutes ago, scott2020 said:

It has 212k on it, but I also found out the previous owner had replaced the head about 3000 miles ago on that side.  It wasn't done at a shop... so maybe something broke loose or something.

 

Sounds like it could get expensive.  Do you think it would be 4, 8, 12, or more hour job?

 

Thank you again!

Impossible to say without actually seeing it, and seeing what the problem actually is.

 

If the head has alot of miles on it, or, if you're not sure what the previous owner actually did (or if he knew what he was doing), I'd be yanking both and have them both completely redone - magnafluxed for cracks, new seats, valves, guides, springs, keepers, pushrods, rockers, etc., etc. ... but only after being sure the cam, lifters and timing chain are all good.

 

This can be a can of worms, though ... meaning if the block has over 200k on it, does it make sense to spend alot of money freshening up the top end? Hard to say. Much easier, but not necessarily cheaper to throw a new crate engine in there from a reputable ENGINE builder (not GM).

[Jsdirt]

42 minutes ago, riverbanks said:

Yep,that's bad plug wires

You're sure about that??

 

I don't know what the other guys are hearing, but that sounds clearly to be a valve train issue from where I'm sitting.

 

EDIT: Volume up, I do hear the sparking. Definitely check that first

[riverbanks]

Do as mentioned earlier,watch in limited light,you'll see the stray Arc from the bad wire(s)

[riverbanks]

Sure about it online?I offer advice,nothing written on stone,lol

[Jsdirt]

See my edit above

 

[riverbanks]

Right on,all to help a fellow motorist

[Jsdirt]

You guys either have better speakers, better ears, or BOTH.  Too much gunfire for me I guess. 

 

This is a great example for the OP how fickle internet diags can be. I heard one thing, you guys heard another, turn my volume up and now I get it, lol.

[riverbanks]

And we all can be wrong,I ain't got a nickel in it,but the forum is a great help,to either reassure or to think outside the box,I get tunnel vision,that's why I'm here, lol

[scott2020]

I appreciate it.  I don't know a valve cover from a book cover so I'm glad to be able to ask questions with folks with a lot more knowledge than I have!