When driving it spits and sputters like it is misfiring

Tiny
POTETE'
  • MEMBER
  • 1999 CHEVROLET SILVERADO
  • 4.3L
  • V6
  • 2WD
  • AUTOMATIC
  • 270,000 MILES
Replace fuel pump and filter, plugs and wires, distributor cap and rotor, check all the fuses. And still can't figure what's wrong. Help please.
Monday, August 10th, 2020 AT 8:05 PM

3 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,885 POSTS
Hi,

Is the check engine light staying on when the engine is running? Does it flash? If so, you really should have the computer scanned for diagnostic trouble codes. That will point us in the right direction.

Also, is the mileage you listed accurate? If it is, have you checked compression? Have you checked to make sure the catalytic converter isn't plugged?

https://www.2carpros.com/articles/how-to-test-engine-compression

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

Let me know. Also, let me know if there is anything other you can think of that is out of the ordinary.

Take care,
Joe
Was this
answer
helpful?
Yes
No
Monday, August 10th, 2020 AT 10:27 PM
Tiny
POTETE'
  • MEMBER
  • 2 POSTS
The catalytic converters have been hollowed out and I have not checked for compression. But do you think it might be the timing chain or tensioner?
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 1:22 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,885 POSTS
Hi,

If the timing is off due to a stretched chain, it can cause issues. However, I don't feel it would have happened all at once. The idea that the converters are removed can be causing havoc with the air fuel mixture. How long has it been this way and did it tun properly with it like this in the past?

Have you had the computer scanned for diagnostic trouble codes? I would suggest it if you haven't. Here is a quick video showing how it's done:

https://youtu.be/YV3TRZwer8k

I realize most people don't own a scan tool, but most times a parts store will do it free of charge. I recommend having it done. If it can't be driven there, see if you can rent one.

Let me know.
Joe
Was this
answer
helpful?
Yes
No
+1
Tuesday, August 11th, 2020 AT 11:03 PM

Please login or register to post a reply.

Sponsored links