Rough idle and surges when driving when i let of the gas

1987 CHEVROLET BLAZER
130,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
Avatar
PGSWITZER
  • MEMBER
  • 6 POSTS
Engine runs rough. i had 02 sensor code come up i replaced it all so replaced the heat sensor. then code 45 came on so i replace the MAP sensor. still the same but my service engine light wont work at all. whats next? thanks
Dec 19, 2018 at 6:40 AM
Advertisement
Avatar
STRAILER
  • ✓Experienced Mechanic
  • 55,583 POSTS
Hello,

It sounds like you have low compression in one or more cylinders. Here is a guide to help us get started:

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

Please run down this guide and report back. Cheers, Ken
Dec 20, 2018 at 10:53 AM
🔧 Tools & Auto Repair Parts
Find automotive tools, diagnostic equipment, and replacement parts for your next repair.
Shop on Amazon →
Paid affiliate link. As an Amazon Associate, we earn from qualifying purchases.
Add a reply
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 new question

Frequently Asked Problems for This Vehicle