My check engine light is on and once it's cleared it keeps coming back on "running rich".

Asked by Jan 08, 2014 at 10:36 PM about the 2009 GMC Sierra 1500 SLE 4WD

Question type: Maintenance & Repair

I have a 2009 gmc sierra that is
"running rich". The last few times I
started it, it's been having trouble
starting up and twice it's stalled out
and I had to restart it. Took it to a
local shop and they cleared the light
after they said it was running rich.
Why does it keep coming on?

2 Answers

90,705

A few things, ECT sensor could be out of specs or sending the wrong signal, ACT sensor could also do the same, fuel pressure too high, EGO sensors plugged up or bad, the best way to find the problem is take it to a shop that has a scanner that can do live data while driving down the road, that way they can watch all of the ECM's inputs and outputs and locate the ones with a problem.

1 out of 1 people think this is helpful.
600

I changed all my sensors on my 89 gmc when i was having ther same problem. Nothing fixed. Took to my mechanic and they did a pressure test. Leaking intake valve gasket. Replaced, cleaned everything and its running like a champ and no longer running rich.

Your Answer

Add photo

Related Questions

Search GMC Sierra 1500 Questions

GMC Sierra 1500 Experts

#1 dragonflyoffshore
dragonflyoffshore
Reputation 4,920
#2 John Saffrahn
John Saffrahn
Reputation 3,490
#3 Glenn Clingenpeel
Glenn Clingenpeel
Reputation 3,070
View All

Related Models For Sale

Used Chevrolet Silverado 1500
1,732 Great Deals out of 167,272 listings starting at $1,800
Used Ford F-150
2,214 Great Deals out of 208,693 listings starting at $1,499
Used GMC Sierra 2500HD
112 Great Deals out of 14,550 listings starting at $2,650
Used Toyota Tundra
471 Great Deals out of 33,173 listings starting at $2,500
Used Dodge Ram 1500
441 Great Deals out of 11,296 listings starting at $1,000
Used Toyota Tacoma
506 Great Deals out of 38,897 listings starting at $2,900
Used Chevrolet Silverado 2500HD
318 Great Deals out of 26,738 listings starting at $1,250
Used GMC Yukon
358 Great Deals out of 16,994 listings starting at $2,500
Used Chevrolet Tahoe
563 Great Deals out of 27,154 listings starting at $999
Used Ford F-250 Super Duty
347 Great Deals out of 47,432 listings starting at $1,795
Used Chevrolet Camaro
154 Great Deals out of 32,676 listings starting at $1,995
Used Chevrolet Colorado
231 Great Deals out of 23,455 listings starting at $2,200
Used GMC Canyon
84 Great Deals out of 7,544 listings starting at $1,999

Used Cars For Sale

2017 GMC Sierra 1500 SLE 4WD For Sale
200 listings starting at $35,733
2016 GMC Sierra 1500 SLE 4WD For Sale
37 listings starting at $28,900
2015 GMC Sierra 1500 SLE 4WD For Sale
39 listings starting at $26,503
2014 GMC Sierra 1500 SLE 4WD For Sale
43 listings starting at $20,855
2013 GMC Sierra 1500 SLE 4WD For Sale
19 listings starting at $18,490