Trouble Starting/ Engine dies once in awhile while stopped at a light

Asked by Mar 11, 2016 at 03:53 PM about the 1999 GMC Sierra 1500

Question type: Maintenance & Repair

My truck will start just fine after sitting for awhile (i.e. overnight), but if the engine is shut off and I try to start it back up in 5 minutes, 10 minutes, 30 minutes later, its hard to start and takes a little (5 sec).  Always starts eventually. Also, when I am stopped at a light, I will feel the truck is about to die, but if I let off the brake it will catch itself and be fine.  Any ideas on what it could be...I'm thinking fuel pump, but after looking at some of the answers on the site to similar questions, it seems like that's not always the case. Also its not the battery...its brand new.

2 Answers

20

If you let off the brake and it acts differently, then maybe you have a vacuum leak in your brake booster line.

85,355

Hard starting is an indication of leaky fuel injectors, spider lines, and fuel regulator. What size is the motor? So what you do is hook up a fuel pressure gauge to the Schrader valve, then just cycle the key on off until it builds up pressure, should be 56 to 63 lbs. then let it sit with the key off, now just watch the gauge for 3 minutes, the fuel pressure should not drop off more than 5 lbs. If it does, then the injector assembly would need to be replaced as a unit.

Your Answer:

GMC Sierra 1500 Experts

  • #1
    dragonflyoffshore
    Reputation
    5,600
  • #2
    John Saffrahn
    Reputation
    3,920
  • #3
    Glenn Clingenpeel
    Reputation
    3,730
View All

Related Models For Sale

Used Chevrolet Silverado 1500
121 Great Deals out of 11,301 listings starting at $4,500
Used Ford F-150
115 Great Deals out of 11,141 listings starting at $369
Used Toyota Tundra
30 Great Deals out of 1,538 listings starting at $5,488
Used Dodge Ram 1500
25 Great Deals out of 533 listings starting at $2,150
Used Chevrolet Silverado 2500HD
10 Great Deals out of 1,382 listings starting at $3,995
Used Toyota Tacoma
19 Great Deals out of 1,621 listings starting at $5,795
Used GMC Yukon
17 Great Deals out of 1,126 listings starting at $3,995
Used Chevrolet Tahoe
15 Great Deals out of 873 listings starting at $6,999
Used Ford F-250 Super Duty
18 Great Deals out of 876 listings starting at $3,995
Used Chevrolet Camaro
6 Great Deals out of 999 listings starting at $4,500
Used Ford Mustang
21 Great Deals out of 1,216 listings starting at $5,995

Used Cars For Sale

2018 GMC Sierra 1500 For Sale
19 Great Deals out of 8,360 listings starting at $22,280
2017 GMC Sierra 1500 For Sale
3 Great Deals out of 567 listings starting at $24,940
2016 GMC Sierra 1500 For Sale
13 Great Deals out of 509 listings starting at $22,750
2015 GMC Sierra 1500 For Sale
11 Great Deals out of 518 listings starting at $19,988
2014 GMC Sierra 1500 For Sale
5 Great Deals out of 307 listings starting at $15,995

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.