i have a 1989 ford f150 pickup and today my rpm is jumping and while driving its starting to jerk. what could it be

Asked by May 01, 2014 at 05:11 PM about the 1989 Ford F-150

Question type: Maintenance & Repair

7 Answers

265

I'm curious as well I have a 92 that wants to jerk as your driving. Thanks

1 of 1 people found this helpful.
24,925

A couple of quick checks: Warm the engine and spray the plug wires with a soapy mix of dish soap and water with a spray bottle. You should hear a snapping sound or maybe even see the spark jump. If everything is ok there, It's likely that either the Ignition Coil or Ignition Module is failing. The Tachometer is driven directly off of the coil and those E-core coils will fail internally while testing ok on the bench.

1 of 1 people found this helpful.

Throttle position sensor. Had same/similar problem with mine (mine's manual and only did it in neutral, so not sure how it would present in an automatic) Had all sorts of diagnostics and theories but turned out to be the throttle position sensor which is actually a really easy fix, so try that first.

24,925

While that's a nice guess, I wouldn't go throwing parts at a problem without a diagnosis first. Just a waste of money.

Are you referring to me? If his problem is the same as mine was, and I believe it is, then it's DEFINITELY the TPS.

24,925

Good luck with that. As a Master Certified Automotive Technician (Ford Motor Company and ASE), I can tell you that a TPS can have similar symptoms to many other failures. The only true way to diagnose a TPS failure is to check the signal back to the PCM. To have such confidence in something that worked for you once is fool-hardy. If I tried to repair vehicles with "I know what that is because I saw it once before" I certainly wouldn't be in the position I am in today - one of 12 Master Certified Technicians repairing and Maintaining a fleet of over 800 Police vehicles. Indeed. Guess work doesn't work.

2 of 2 people found this helpful.
265

I have a problem with the truck runs great till the engine warms up then after warm up the truck wants to jerk/Buck while driving and sometimes dies. if I put the truck in neutral or park revs fine idles fine. Any help thanks

2 of 2 people found this helpful.

Your Answer

Add photo

Related Questions

F-150

Looking for a Used F-150 in your area?

CarGurus has 195,050 nationwide F-150 listings starting at $290.

ZIP:

Search Ford F-150 Questions

Ford F-150 Experts

#1 OJ
OJ
Reputation 8,480
#2 dandyoun
dandyoun
Reputation 4,420
#3 tennisshoes
tennisshoes
Reputation 2,940
View All

Related Models For Sale

Used GMC Sierra 1500
776 Great Deals out of 68,592 listings starting at $1,800
Used Ford F-250
463 listings starting at $4,690
Used Ford Mustang
683 Great Deals out of 44,980 listings starting at $750
Used Ford Ranger
171 Great Deals out of 5,630 listings starting at $1,200

Used Cars For Sale

2018 Ford F-150 For Sale
701 listings starting at $29,070
2017 Ford F-150 For Sale
54 Great Deals out of 125,685 listings starting at $18,199
2016 Ford F-150 For Sale
107 Great Deals out of 9,637 listings starting at $16,990
2015 Ford F-150 For Sale
224 Great Deals out of 8,748 listings starting at $15,990
2014 Ford F-150 For Sale
351 Great Deals out of 12,452 listings starting at $9,900

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.