Jerking under any accelerating conditions?

Tiny
DESHAWN93
  • MEMBER
  • 2000 MERCURY COUGAR
  • 138,300 MILES
I have a 2000 mercury cougar with the 2.5 and a 5 speed manual transmission. When I start the car it will idle fine, in reverse the vehicle is fine, but when I put the vehicle into 1-5th gear the vehicle****** violently. In an undrivable manner, and the check engine light will flash each time it******. Already changed MAF, plugs, wires, DMFE, valve cover breather hoses, fuel filter, vacuum regulator. VEHICLE SHOWS NO CODES WHEN SCANNED
Do you
have the same problem?
Yes
No
Monday, December 19th, 2011 AT 7:46 AM

4 Replies

Tiny
DESHAWN93
  • MEMBER
Also changed TPS
Was this
answer
helpful?
Yes
No
Monday, December 19th, 2011 AT 7:52 AM
Tiny
MHPAUTOS
  • EXPERT
Did you scan transmission or just engine?
Was this
answer
helpful?
Yes
No
Monday, December 19th, 2011 AT 11:09 AM
Tiny
DIABLERIST
  • MEMBER
I have this same problem and it is starting to really drive me nuts. I have recently replaced the EGR and TPS for other issues, the wires and plugs are about 3 years old and my Check Engine light comes on occasionally, but eventually goes off on its own. Engine temperature does not seem to be a factor and it will jerk when accelerating or at an even speed, but does not when at idle. I have seen that it could be one of the ignition coil packs, but how would one go about testing that theory?
Was this
answer
helpful?
Yes
No
Saturday, August 16th, 2014 AT 6:30 PM
Tiny
DIABLERIST
  • MEMBER
After thinking about it I am guessing that you would check resistance, but how would that link to intermittent problems with spark problems?

I also realized you could use a little bit more info.
It is a 99 2.5L V6 Duratec standard transmission. The problem started directly after I replaced the TPS with a salvage yard replacement. Though it solved my idle problem I thought it being a very used and neglected part, it may be responsible in some way for the jerking (it actually feels like the engine is staling out for that half second so misfire does qualify) so I replaced it with a new TPS. It did not help. I have checked all the plug and wire connections and they are all solid, I have checked the EGR system for disconnected hoses and there are no codes as far as I know(every time I go to have it checked the CE Light is off). Previous to this I had it checked quite often since I was in school for Auto Tech and the only thing it was throwing were Oxygen Sensors which I had replaced.

That is all I can think of right now.

Cheers
Was this
answer
helpful?
Yes
No
Saturday, August 16th, 2014 AT 7:29 PM

Please login or register to post a reply.

Recommended Guides