SPONSORED LINKS

Engine misfires

Tiny
ACTIONAUTOREPAIR
  • MEMBER
  • 1999 CHEVROLET SUBURBAN
  • 5.7L
  • V8
  • 4WD
  • AUTOMATIC
  • 150,000 MILES
While accelerating it misses.
Wednesday, March 28th, 2018 AT 9:11 AM

9 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good morning.

The first thing I would do is basics, such as spark plugs. That is the most common reason for miss fire under load.

How old are your spark plugs?

Are there any codes?

Roy
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Wednesday, March 28th, 2018 AT 10:03 AM
Tiny
ACTIONAUTOREPAIR
  • MEMBER
  • 19 POSTS
Spark plugs new, also new brain but, scanner is not reading it.
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 1:03 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Is the scanner reading any info?

Have you checked fuel pressure? Low fuel pressure will cause miss fires.

Roy
Was this
answer
helpful?
Yes
No
-1
Tuesday, April 3rd, 2018 AT 1:06 PM
Tiny
ACTIONAUTOREPAIR
  • MEMBER
  • 19 POSTS
Also several other parts have been replaced.
Except the spider fuel injectors not replaced.
Last time it was running I could smell fuel.
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 1:09 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Thats common when the pressure regulator is leaking into the intake. Take the upper intake off and inspect. Bet you find puddles of fuel.

Roy
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 1:11 PM
Tiny
ACTIONAUTOREPAIR
  • MEMBER
  • 19 POSTS
My hubby isn't here to say but I believe the pressure regulator has been replaced if not then the fuel pressure was checked let me ask him.
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 1:29 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Pressure regulator is part of the spider. It is rare just to replace the regulator.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 1:48 PM
Tiny
ACTIONAUTOREPAIR
  • MEMBER
  • 19 POSTS
He said regulator was replaced
About the spider I thought it had but not positive
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 2:08 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Thats where I would start.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, April 3rd, 2018 AT 2:17 PM

Please login or register to post a reply.

Related Engine Misfire Content

Intermittent Misfire
VIDEO
Intermittent Misfire
Instructional repair video
Misfire Random Code P0300
GUIDE
Misfire Random Code P0300
The world of automotive diagnostics can be complex, with numerous codes and potential issues to keep track of. One of the more common engine diagnostic codes is P0300, which...
VIEW MORE

Sponsored links