misfire on acceleration.

355

Asked by Dan Jun 07, 2013 at 06:07 PM about the 1990 Ford F-150 XLT Lariat 4WD LB

Question type: Maintenance & Repair

i have a 1990 f150 larait 300 6cyl. i recently did a tune up and got cyl 4 and 2 reversed on the cap.. i feel dumb but now it runs alright at idle. took it for a test drive and i made it about a block and it started to misfire badly and stumble. it would accelerate but not at the rate it should. i think i need to adjust timing? also there is an intake gasket leak and a friend told me that the leak may be causing it because there is too much air getting into the cylinders. any possibility that could cause it? i appreicate any help because this is stumping me. the fuel pump is only a couple years old. i just replaced the fuel filter.

2 Answers

57,975

While the 300 is a great workhorse - it is prone to warping the exhaust manifold and taking the intake with it. When you do address the concern, don't try to fudge it - you'll only have to do it again. Gaskets help but they aren't the fix. Tennisshoes knows what he's talking about here - vacuum leaks cause all kinds of drivability concerns as well as the carbon tracking issue)

355

thank you for your answers. i did get it fixed, the timing was badly off. runs much better now.

Your Answer:

F-150

Looking for a Used F-150 in your area?

CarGurus has 13,473 nationwide F-150 listings starting at $3,888.

Postal Code:

CarGurus Experts

  • #1
    OJ
    Reputation
    41,870
  • #2
    Gene Arnett
    Reputation
    15,990
  • #3
    Rowefast
    Reputation
    15,490
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used GMC Sierra 1500
141 Great Deals out of 7,842 listings starting at $4,944
Used Ford F-250
6 listings
Used Ford Ranger
25 Great Deals out of 690 listings starting at $6,445
Used Ford Mustang
35 Great Deals out of 1,596 listings starting at $7,999
Used Ford Explorer
62 Great Deals out of 1,825 listings starting at $6,990

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. Content will be removed if CarGurus becomes aware that it violates our policies.