QuestionI have a 1991 Suburban, 350, auto, gas, 155,000 miles. Lately, after driving for 15-20 minutes, it develops a wierd miss, spitting back thru the carb, etc. Until this happens, it runs like brand new. I've had the truck for 3 years and have never tuned it up. I have replaced the air and fuel filters, and the pcv valve. The first time that it happened, I pulled the air filter out, and it sat for about 10 minutes. I took it for about a 5 minute ride, w/out an air filter, and it ran perfect. I thought that I found it, and replaced the air filter. That's when I found out that I have to drive it for 15-20 minutes before it does it again. Can an ignition wire, spark plug, cap, or rotor be bad, but run great until warm? Like I said, it runs perfect until this happens. Any ideas? Thanks very much.
AnswerAbsolutely!
At a minimum, you should replace the spark plugs, spark plug wires, distributor cap and rotor.
The plug wires, in particular, suffer from the tremendous heat generated by today's engines. It is likely that this is where your problem is, but a full tune-up is in order.
