1998 Chevy Silverado misfiring rapidly! Help please!


Asked by Sep 18, 2016 at 08:17 AM about the 1999 Chevrolet Silverado 1500 3 Dr STD 4WD Extended Cab SB

Question type: Maintenance & Repair

I was driving my truck the other day and it was
running fine and all of a sudden it started running
extremely rough and misfiring like crazy. It also
started running really rich and also gas is leaking
out exhaust pipes. Changed the spark plugs last
night and it was doing the exact same thing if not
worse than before. What could it be?

7 Answers

Tom Demyan

If it was misfiring, you would have a Check engine light, did you scan for codes yet?


Sounds like a bad fuel pressure regulator.


Yeah the check engine light is on and it flashes as well which means misfire I think. Also about a year ago the catalytic converter was removed and it was straight piped. Not sure if this would have something to do with it.


Codes say that Bank 1 and Bank 2 lean. And multiple misfire.


You have fuel dripping out of tail pipe and a computer that thinks it's running lean. I'd check for a vacuum leak, fuel pressure, and the O2 sensor is going to give false readings to the ECU without the cat present.


^ and that's assuming you don't have any actual mechanical trouble like a bad knock/cam/crank sensor or timing chain.


I'll check those today. It just shakes the truck to pieces when you give it gas. It's got a bad miss to it.

Your Answer

Add photo

Related Questions

Silverado 1500

Looking for a Used Silverado 1500 in your area?

CarGurus has 144,713 nationwide Silverado 1500 listings starting at $1,995.


Search Chevrolet Silverado 1500 Questions

Chevrolet Silverado 1500 Experts

#1 John Carson
John Carson
Reputation 1,590
#2 Silverado_owner_2006
Reputation 1,390
#3 Andrew Olsen
Andrew Olsen
Reputation 1,310
View All

Related Models For Sale

Used GMC Sierra 1500"
1,024 Great Deals out of 56,926 listings starting at $2,300
Used Ford F-150"
3,267 Great Deals out of 216,697 listings starting at $1,500
Used Dodge Ram 1500"
522 Great Deals out of 13,739 listings starting at $995
Used Toyota Tundra"
621 Great Deals out of 26,774 listings starting at $2,500
Used Toyota Tacoma"
617 Great Deals out of 30,502 listings starting at $2,850
Used Chevrolet Tahoe"
1,074 Great Deals out of 36,045 listings starting at $1,700
Used Chevrolet Camaro"
798 Great Deals out of 38,822 listings starting at $2,650
Used Chevrolet Silverado 2500"
3 Great Deals out of 271 listings starting at $3,499
Used Ford F-250 Super Duty"
444 Great Deals out of 43,001 listings starting at $2,250
Used Chevrolet C/K 1500"
1,138 listings starting at $2,400

Used Cars For Sale

2017 Chevrolet Silverado 1500 For Sale
8 Great Deals out of 55,355 listings starting at $22,113
2016 Chevrolet Silverado 1500 For Sale
307 Great Deals out of 35,002 listings starting at $17,443
2015 Chevrolet Silverado 1500 For Sale
284 Great Deals out of 8,171 listings starting at $14,948
2014 Chevrolet Silverado 1500 For Sale
432 Great Deals out of 11,058 listings starting at $10,990
2013 Chevrolet Silverado 1500 For Sale
264 Great Deals out of 6,835 listings starting at $7,400