Sputters backfires

1999 JEEP CHEROKEE
240,000 MILES • 4.0L • 6 CYL • 2WD • AUTOMATIC
Avatar
ROBERTDD
  • MEMBER
  • 1 POST
So I have changed, wires, plugs, rotor, cap, MAP, IAC, TPS, ECM, all new electrical under hood, fuel pump and filter because their both one unit, alternator, air temperature sensor, and yet it still sputters when it is cold or hot, but not all the time. It can start up and ruin fit a good four hours and then mess up or mess up right away and then run fine later but the back fire dies cine out of intake. I am stumped. please help, thanks.
Nov 18, 2016 at 7:12 AM
Advertisement
Avatar
HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
scan for codes and check fuel pressure with a gauge auto parts rent it. check for a vacuum leak then pull valve cover and see if any pushrods are bent/off etc or a rocker worn out or loose. see link.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
Nov 18, 2016 at 12:22 PM
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.