1999 Chevrolet Tahoe sputtering

BETTINA ROMANO

MEMBER
1999 CHEVROLET TAHOE
5.7L
V8
4WD
AUTOMATIC
233,437 MILES

My service engine light came on a year a go had diagnostic test read a misfire I changed all the plugs and wires still engine light on and was blinking for the last 6 months I rarely drive it opened the Hood the other day to find a soark plug wire was disconnected from distribute I believe I also noticed a delayed start it was running good check engine light is off now and occasionally comes on starts stronger but is sputtering badly not sure if it's bad coil I ordered one but it's possible I have run my truck for the last year on 7 cylinders should I replace all of them or check to see if the one that was disconnected it fuel soaked I still feel it miss fire I do all my own work not sure what kinda damage I did I love my truck over 233,000 miles any ideas would be greatly appreciated also took my oil cap off and had a tinge of gasoline smell and when I changed plugs last year 1 was badly eroded

1 Reply

CARADIODOC

MECHANIC
33,916 POSTS

Please use some punctuation, otherwise that huge sentence can be read many different ways and it doesn't make sense.

The flashing Check Engine light is serious and means to stop the engine right away. Too much unburned fuel is going into the exhaust system where it will overheat and damage the expensive catalytic converter. If you remember the specific fault code number, that will indicate which cylinder is misfiring

One thing to understand about those fault codes is the Engine Computer compares sensor readings and operating conditions to each other to determine when there's a problem. Once it sees a problem and sets a fault code, it knows that information can't be trusted, so it suspends some tests that rely on it. Even though the Check Engine light might turn off at times, the fault code is still there, so other problems might not get detected. The place to start now is by having the codes read again and recorded, then have them erased. The people at many auto parts stores will do that for you for free. Then see which code(s) come back. With the exact code numbers we should be able to figure out where to go next.