Exhaust with no muffler or catalytic converter rides rough and sputters when accelerating

1996 GMC SIERRA
178,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
Avatar
BIGJOHN01
  • MEMBER
  • 2 POSTS
Truck rides rough and sputters when I get on the gas. After the truck gets hot, I can feel it clear up and drive better. Even the exhaust sounds better. Just had new exhaust pipes installed with no muffler.
Dec 7, 2016 at 10:56 PM
Advertisement
Avatar
HMAC300
  • ✓Experienced Mechanic
  • 48,601 POSTS
scan for codes and check fuel pressure with a gauge auto parts rent it. See link.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

also, check for a vacuum leak and soft vacuum hoses if soft replace them.
Dec 8, 2016 at 4:22 AM
Avatar
STRAILER
  • ✓Experienced Mechanic
  • 55,224 POSTS
Hey Bigjohn

It sounds like it could be a mass air flow sensor that has gone bad or is dirty, also scan for trouble codes, here are a couple of guides to help you,


https://www.2carpros.com/articles/mass-air-flow-service

and

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please let us know happens so it will help others.

Best, Ken


Dec 12, 2016 at 4:01 AM
Avatar
BIGJOHN01
  • MEMBER
  • 2 POSTS
I've put new plugs, wires , cap and rotor. Replaced mass air flow sensor. New fuel filter, fuel pressure regulator and injectors. My exhaust broke loose and had to fix it cheap. Got a feeling it's either the throttle position sensor or the O2sensors
Dec 12, 2016 at 8:03 AM
Avatar
STRAILER
  • ✓Experienced Mechanic
  • 55,224 POSTS
Do you have an OBD2 plug? or is it an OBD1 truck?

Dec 12, 2016 at 8:17 AM
Avatar
HMAC300
  • ✓Experienced Mechanic
  • 48,601 POSTS
scan for codes that is one of the first things to do also check for a vacuum leak because it sounds like computer is richening the fuel mix to take care of vacuum leak also running with no cat and no secondary O2 is not a good idea.
Dec 12, 2016 at 8:39 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.