1986 Mercury Marquis runs rough especially during accelerat

Tiny
RONFJR
  • MEMBER
  • 1986 MERCURY MARQUIS
  • V8
  • 2WD
  • AUTOMATIC
  • 80,000 MILES
This symptom starting occuring suddenly. The engines seems to run a little rough but is most noticeable when coasting at 20mph then pushing on the gas pedal a little, at that point the car seems to shake a little and it sounds like the engine is running rough, and maybe a slight power loss is felt. If you continue to accelerate it seems to smooth out. It will do the same thing when coasting at other mph's then accelerating but it's not near as pronounced as at 20mph. I think I can tell the engine is not running as smooth as it should when just sitting in drive and stopped, but it's hard to notice. It seems most noticeable at any time when first pushing down on the gas pedal. Any help appreciated.
Do you
have the same problem?
Yes
No
Sunday, February 24th, 2008 AT 4:18 PM

1 Reply

Tiny
BLACKOP555
  • EXPERT
I would like you to check for a plugged exhaust system. Hook up a vaccum guage and run the vehicle till its warm then turn it off and hook up the vaccum guage, fire it back up and run the vehicle at 2500 rpms for 2 minutes, if you have to keep giving it more gas for it to maintain 2500 rpm's or the vaccum slowly but steadily goes down then you have a plugged exhaust system.

Also check the timing.
Was this
answer
helpful?
Yes
No
Sunday, February 24th, 2008 AT 6:48 PM

Please login or register to post a reply.

Recommended Guides