Engine is backfiring through exhaust. Bad valve?
Jun 12, 2021 at 3:49 PM
Engine backfiring
1997 FORD E-SERIES VAN
39TB
- MEMBER
- 3 POSTS
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ASEMASTER6371
- ✓ASE Certified Mechanic
- 52,796 POSTS
Good evening,
I would start by checking the compression. It could be a valve if the compression is low.
https://www.2carpros.com/articles/engine-backfires-while-running
https://www.2carpros.com/articles/how-to-test-engine-compression
It could also be a broken valve spring. The valve may not be closing all the way and it backfires out that cylinder. I attached a picture of the valve spring for you. Once one of the coils break, the spring will not have enough pressure to hold the valve closed.
Roy
I would start by checking the compression. It could be a valve if the compression is low.
https://www.2carpros.com/articles/engine-backfires-while-running
https://www.2carpros.com/articles/how-to-test-engine-compression
It could also be a broken valve spring. The valve may not be closing all the way and it backfires out that cylinder. I attached a picture of the valve spring for you. Once one of the coils break, the spring will not have enough pressure to hold the valve closed.
Roy
Image (Click to enlarge)
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Jun 12, 2021 at 5:08 PM
Thank you Roy, I will do a compression test before I start pulling valve covers. Lee
Jun 12, 2021 at 6:37 PM
ASEMASTER6371
- ✓ASE Certified Mechanic
- 52,796 POSTS
You are welcome.
Let us know if you have any other questions.
Always glad to help.
Roy
Let us know if you have any other questions.
Always glad to help.
Roy
Jun 13, 2021 at 3:34 AM
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