Had a problem with our '00 Silverado 4x4 with 5.3 engine, over 110,000 miles. It would start fine when cold but when hot, it would crank over for more than 5 seconds before it would start, then stumble for a few seconds before the idle was smooth. Gas mileage was not affected, and there was no black smoke when it did start, but I could smell gasoline. I replaced the fuel filter, installed new Bosch platinum plugs, new plug wires, cleaned K&N air filter, and cleaned out the air intake. The problem remained, and I didn't have the time to troubleshoot it, so my wife took it to the Chevy dealer. First, they replaced the O2 sensor, but that didn't fix it so we took it back. The next trip to the dealer they replaced the fuel regulator & the spark plugs with AC Delco brand. They claimed the hard starting was caused by the Bosch plugs not firing until the rpm's were up. I've been working on cars for 30 years and have never heard of this. Anyone else seen it? Thanks, Robert
- posted
17 years ago