what would cause a 1999 Chevy C3500 with the 5.7 engine to fluctuate rpm between 50 and 60 miles an hour backfire and almost stall? I've gone as far as replacing the fuel pump with a new.


Asked by Feb 06, 2015 at 10:16 PM about the 1999 Chevrolet C/K 3500 Reg. Cab 2WD

Question type: Maintenance & Repair

2 Answers

Steven Martinez

Did you do the filter? Could just need a tune up or maybe a maf sensor. Is it putting out any codes?


thank you for your answer Steve, I changed the cam position sensorthe truck ran great for about 15 minutes with lots of power then act it up the same way check engine light was on rpm stop back down computer like reset itself and was backfiring , I change the cap and rotor ran smoothly not as much power but no check engine lights or rpm fluctuation so far I will know on Monday when I get to drive it further but got it past 70 mph I have yet to see if I resolved the sensor issue???

Your Answer

Add photo

Related Questions

Search Chevrolet C/K 3500 Questions

Chevrolet C/K 3500 Experts

#1 cooldad47
Reputation 180
#2 tennisshoes
Reputation 100
#3 Dieselman1990
Reputation 90
View All

Related Models For Sale

Used Chevrolet C/K 2500"
285 listings starting at $1,995
Used Dodge Ram 3500"
109 Great Deals out of 2,483 listings starting at $4,995
Used Ford F-350 Super Duty"
450 Great Deals out of 26,915 listings starting at $3,600
Used GMC Sierra 3500"
7 Great Deals out of 310 listings starting at $5,495
Used Chevrolet C/K 1500"
1,140 listings starting at $2,400
Used Chevrolet Silverado 1500"
2,454 Great Deals out of 144,271 listings starting at $1,995
Used Ford F-250 Super Duty"
463 Great Deals out of 42,865 listings starting at $1,000
Used Dodge Ram 2500"
159 Great Deals out of 5,799 listings starting at $2,289