i've owned it for about a year and a half now and it's been running great. then i drove it to kansas city and back twice and each time it started to put and backfire a little bit once i hit high speeds on the highway. ever since, it's gotten worse and worse and now it happens mostly on hills and still highways.
any suggestions?
it's at about 100,000 miles
2007-11-02 15:23:37 · 4 answers · asked by BAMF B 1 in Cars & Transportation ➔ Car Makes ➔ GMC
I own a shop, and can think of a couple of reasons one will backfire. The most common cause is the spark plugs breaking down. The other is the camshaft has a lobe or two that is worn down, and not opening the valves as far as it should. It is also possible the timing chain is worn out, and on the verge of jumping teeth, but I would place my money on the spark plugs. On a 95 a scan tool won't do much for you. If you don't have a check engine light on, then there won't be any codes stored in it to retrieve. A quick vacuum test would tell you a lot about the problem, and this rings true if its someting such as the exhaust plugged up, but I have my doubts it would be that.
Glad to help out, Good Luck!!!
2007-11-03 03:07:26 · answer #1 · answered by Anonymous · 0⤊ 1⤋
Have the exhaust checked for restrictions and have it tuned up. Sounds like the exhaust is starting to plug up.
2007-11-02 15:41:47 · answer #2 · answered by johnny b good 4 · 0⤊ 0⤋
Have the computer scanned then it might be time for a tune-up if you havent had one for a while.There is a lot of things that could be causing this.
2007-11-02 17:48:47 · answer #3 · answered by Johnny 4 · 0⤊ 1⤋
Have you ever replaced the spark plugs ??
2007-11-02 15:55:30 · answer #4 · answered by tronary 7 · 0⤊ 0⤋