Multiple Misfires

drtbikerbc · July 2, 2004

I have a '98, 350 Silverado. When pulling a trailer up a hill, the service engine light begins to flash and the truck loses power. This will also occur when doing 75mph on the freeway and going up a hill (without towing anything). It keeps showing MANY misfires on the #5 Cylinder. I have replaced: Cap, Rotor, Plugs, Wires (found the old wires were arcing to manifold), Fuel Filter (3 times), Fuel pump and the #5 injector----NONE of which solved the problem. I have heard that these engines are notorious for having bad FP Regulators but I am curious if anyone else has had this problem before I go to the trouble of changing the regulator.

snoman · July 2, 2004

How does the plug look in number 5 cylinder?

drtbikerbc · July 2, 2004

I haven't looked at it recently. The truck has 60K on it and it has had the problem since I bought it with 38K miles on it. I replaced the plugs at about 42K and I didn't notice it being different from the others at the time.

snoman · July 2, 2004

You should pull it right after is misses a lot just to see if there are any other problems before you go further.

sxmax · July 2, 2004

If indeed the fp regulator is bad, you should be able to unhook the line that runs to it at idle. If there is vapor coming through it then more than likely it is bad, because from my understanding they should be complete dry when you unhook them on ones that are working, but I am no means an ASE mechanic but I did stay at a holiday inn express last night!