How do you know if it is a bent valve or if it is a sensor?

Tiny
MAYS0219
  • MEMBER
  • 2001 FORD FOCUS
  • 4 CYL
  • 2WD
  • MANUAL
  • 191,000 MILES
Rolled in reverse for about a quarter of a mile but while going in reverse it was in first gear lost all brakes so just started rolling while rolling it backfire very loudly. How do I know if the valves are bent?
Do you
have the same problem?
Yes
No
Friday, April 23rd, 2021 AT 11:52 PM

1 Reply

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,014 POSTS
Hi,

A backfire is usually caused by excessive fuel entering the engine. Take a look through this link:

https://www.2carpros.com/articles/engine-backfires-while-running

Now, is the engine still running? As far as checking for a bent valve, the easiest thing to do is a compression test. If you have a bent valve, it will be stuck open and there will be little to no compression in that cylinder.

Here is a link that shows how it is done:

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

Let me know what you find or if you have other questions. Also, if you can record it cranking and upload it for me to hear, I should be able to tell you if there is a compression issue.

Take care,

Joe
Was this
answer
helpful?
Yes
No
Saturday, April 24th, 2021 AT 10:06 PM

Please login or register to post a reply.

Sponsored links