I have a 1991 gmc 2500. It eats gas somethin awfull. I changed the spark plugs, and it passed smog, now it idles a little rough, and still eats gas. What do i do...

Asked by Dec 16, 2013 at 09:25 PM about the 1991 GMC Sierra 2500 2 Dr C2500 SLX Standard Cab LB

Question type: Maintenance & Repair

2 Answers

1,795

are you getting any service engine codes

83,175

Colder temps will cause an increase in fuel consumption, check the thermostat, make sure it is operating properly and not stuck open, make sure the air filter is clean, double check base engine timing, this is a OBD1 system so the ignition timing can be adjusted, then you need to have the codes checked for out of specs sensors.

Your Answer

Add photo

Related Questions

Search GMC Sierra 2500 Questions

UK Questions

Are you a UK consumer? CarGurus now has a discussion forum in the UK.

GMC Sierra 2500 Experts

#1 Rowefast
Rowefast
Reputation 150
#2 FordNut
FordNut
Reputation 100
#3 tennisshoes
tennisshoes
Reputation 90
View All

Related Models For Sale

Used GMC Sierra 1500
1,020 Great Deals out of 59,988 listings starting at $1,299
Used Ford F-150
3,031 Great Deals out of 207,234 listings starting at $1,990
Used Ford F-250
566 listings starting at $1,342
Used GMC Sierra 3500
8 Great Deals out of 303 listings starting at $7,300
Used Chevrolet C/K 2500
262 listings starting at $2,000

Used Cars For Sale

2004 GMC Sierra 2500 For Sale
37 listings starting at $7,500
2001 GMC Sierra 2500 For Sale
8 listings starting at $9,788