Idle issues

Asked by Afstuve Jan 01, 2017 at 03:21 AM about the 2002 Ford F-150 XL SuperCab SB

Question type: Maintenance & Repair

I have a 2002Ford F150 and am having unsteady
idles urging when in drive and brake is applied,
stalling also when in drive and brake is applied
then released.  Have also noticed hissing from
front and rear of truck along with a pumping,
putting sort of noise as well. Not sure whether this
is a fuel pump issue, air flow sensor, vac. line leak,
or some other issue causing all of this.  Appreciate
any help that is given as I am able to perform
certain repair &maintenance on truck but am
limited in my mechanical skills.

2 Answers

159,085

It is possible that there is an issue with the power brake booster. The booster is supplied with vacuum from the intake manifold. This vacuum is used in the booster to amplify the pressure you put on the brake pedal when stopping. I would first locate the booster vacuum line that runs between the manifold and booster and make sure it is not cracked or otherwise degraded. If it looks good I would suspect a faulty brake booster and replace it. The loss of vacuum is likely the issue as to why it is not running correctly properly. The vacuum leak could be from somewhere else under the hood also.

I have the exact same truck with a 5.4l that has this issue. The plastic intake manifold is known to crack which causes a vacuum leak. Dorman makes a replacement manifold with upgraded O-ring gaskets for about $200. It takes a couple of hours for a home mechanic to replace it.

Your Answer:

CarGurus Experts

  • #1
    OJ
    Reputation
    42,520
  • #2
    Gene Arnett
    Reputation
    16,040
  • #3
    Rowefast
    Reputation
    15,860
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet Silverado 1500
210 Great Deals out of 5,957 listings starting at $2,975
Used GMC Sierra 1500
138 Great Deals out of 7,231 listings starting at $3,950
Used Ford F-250 Super Duty
25 Great Deals out of 1,210 listings starting at $7,995
Used Toyota Tundra
34 Great Deals out of 1,163 listings starting at $8,500
Used Toyota Tacoma
60 Great Deals out of 1,065 listings starting at $8,708
Used Dodge RAM 1500
4 Great Deals out of 71 listings starting at $4,000
Used Ford Ranger
18 Great Deals out of 1,553 listings starting at $2,888
Used Ford Mustang
61 Great Deals out of 1,274 listings starting at $4,995
Used Chevrolet Silverado 2500HD
15 Great Deals out of 1,298 listings starting at $8,995
Used GMC Sierra 2500HD
19 Great Deals out of 1,631 listings starting at $9,988
Used Ford F-350 Super Duty
41 Great Deals out of 2,606 listings starting at $8,995
Used Ford Explorer
78 Great Deals out of 2,097 listings starting at $2,999

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.