Is it the PCM or just several problems

Asked by Jan 07, 2017 at 04:31 AM about the 2008 Chevrolet Silverado 1500 LT1 Crew Cab

Question type: Maintenance & Repair

So about a month ago I was driving and as I was
accelerating my truck shifted hard than my check
engine light started flashing now I have 7 different
codes that came on at the same time one is device
voltage low another is device voltage high than I
have two codes for the same misfire on cylinder 7
than I also have a code for my EVAP and another
for the generator which I already replaced and after
letting my computer reset the truck started fine ran
for about a minute than started misfiring again do
y'all think it's a computer or something else

1 Answer


If you didn't use a good scan tool to reset the computer it didn't reset properly, the problem sounds like it is thermally related so the misfire could be anything from a sensor out of specs to an internal engine vacuum leak on number 7. Don't disconnect the battery to reset the ECM you could cause the BCM to loose the factory presets and then some if not all of the accessories will stop working. Have the ECM cleared properly then drive it around until the light comes back on and then have the codes rechecked, most parts stores can do this, and then these codes will be fresh codes and not past memory codes that may or may not have been viable due to unstable power supply. You may want too buy a preset saver tool from your local parts store, it uses a 9 volt battery and plugs into a working lighter or power port. Better ones plug directly into the OBD2 port and use a external power supply like a jump box. And please make sure the grounds are good, especially the sensor grounds. like they say basics first.

Your Answer

Chevrolet Silverado 1500 Experts

  • #1
    John Carson
  • #2
  • #3
    Andrew Olsen
View All

Related Models For Sale

Used GMC Sierra 1500
892 Great Deals out of 58,860 listings starting at $1,980
Used Ford F-150
2,490 Great Deals out of 220,183 listings starting at $1,222
Used Chevrolet Silverado 2500HD
377 Great Deals out of 31,252 listings starting at $1,950
Used Dodge Ram 1500
322 Great Deals out of 9,609 listings starting at $800
Used Toyota Tundra
529 Great Deals out of 36,822 listings starting at $1,500
Used Toyota Tacoma
442 Great Deals out of 40,250 listings starting at $2,600
Used Chevrolet Tahoe
634 Great Deals out of 37,191 listings starting at $795
Used Chevrolet Colorado
285 Great Deals out of 42,849 listings starting at $1,900
Used GMC Sierra 2500HD
136 Great Deals out of 15,261 listings starting at $2,750
Used Ford F-250 Super Duty
384 Great Deals out of 44,881 listings starting at $1,500
Used Ford Mustang
278 Great Deals out of 38,285 listings starting at $1,995
Used Dodge Charger
238 Great Deals out of 33,021 listings starting at $495

Used Cars For Sale

2018 Chevrolet Silverado 1500 For Sale
33 Great Deals out of 86,336 listings starting at $19,167
2017 Chevrolet Silverado 1500 For Sale
194 Great Deals out of 11,265 listings starting at $16,409
2016 Chevrolet Silverado 1500 For Sale
223 Great Deals out of 6,591 listings starting at $16,942
2015 Chevrolet Silverado 1500 For Sale
340 Great Deals out of 10,365 listings starting at $12,888

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.