Running horrible

[Holt50]

well you can check for spark as someone noted earlier, I would also test for fuel pressure. if it was running fine previously and you have fuel pressure and spark then maybe it jumped time or something? just speculating.....

I think your right. I took it to the shop and he said that he turned the distributor and it started fine but then it moved back like something was locking up.

 

[Doubeleive]

timing chain? not sure the obs 5.7l but my 1980 350 trans am did that, pulled the cover off and the timing gear was plastic coated and had worn down just enough to jump time, I managed to fix it with a new gear and chain and just turning it back, luckily no damages.

 

[Holt50]

timing chain? not sure the obs 5.7l but my 1980 350 trans am did that, pulled the cover off and the timing gear was plastic coated and had worn down just enough to jump time, I managed to fix it with a new gear and chain and just turning it back, luckily no damages.

Just picked up my truck and all her did was change the distributor and it's running fine so far. Well the idle goes up and down while on hear but not in park

 

[Holt50]

Just picked up my truck and all her did was change the distributor and it's running fine so far. Well the idle goes up and down in gear but not in park

 

[89Suburban]

timing chain? not sure the obs 5.7l but my 1980 350 trans am did that, pulled the cover off and the timing gear was plastic coated and had worn down just enough to jump time, I managed to fix it with a new gear and chain and just turning it back, luckily no damages.

That was my guess too.

Just picked up my truck and all her did was change the distributor and it's running fine so far. Well the idle goes up and down while on hear but not in park

Interesting.

 

[jcb2]

I had a car that suddenly acted like that. It turned out to be a slipped timing belt.
Hook up a timing light to check it out.

 

[stevedonato]

Why do al these Tahoe's and it's GMC counterpart all seem to have major engine issues at relativly low mileage? They were all based on the bullet proof Silverado, But Silverados seem to run 250,000 to 300,000 miles with out these issues?

 

[Holt50]

Why do al these Tahoe's and it's GMC counterpart all seem to have major engine issues at relativly low mileage? They were all based on the bullet proof Silverado, But Silverados seem to run 250,000 to 300,000 miles with out these issues?

Mine has350.000

 

[willxfs]

As far as the timing chain goes... On my 1998 2door both sprockets in the timing set are metal as well as the chain. I hear the chain can stretch out a bit after a couple hundred thousand miles. I changed both gears and the chain after about 220k miles. I'm sure my chain was stretched a little bit but I didn't really notice any difference after changing out the set. Had a leaking cover so changed all that stuff while I was there. The gear at the base of the distributor tends to wear out and become knife edged or sharpened. This to me has the greater potential to wear out and cause problems compared to the timing chain and gears.