hesitation

[chad snyder]

i just finished giving my truck a full tune up. its a very sharp looking truck and has the 305 vortec v8. it has all the power i need but i lost alot of fuel mileage lately. my problem is while driving down the road i get around 55-60 mph and my truck has a hesitation like its misfiring or not getting gas. since doing my tune up i believe i have a loose wire or a bad wire or even have two wires switched. because i have this hesitation anytime im giving it gas. can anyone let me know what the firing order is on my truck or where i can find it. as well as any ideas on the hesitation while around 55-60 mph. any help would be appreciated

 

chad

[Jeremy WI]

I don't think firing order will do much good because the distributor cap is weird and cylinders should be marked on it, as long as you know that cylinders 1, 3, 5, and 7 are on the drivers side front to back and the passenger side is 2, 4, 6, and 8 you shouldn't be able to screw it up. You should keep wires parallel to each other(not crossing over each other if possible). Definetly use a factory(AC Delco) distributor cap and rotor, some aftermarkets are a little "off" and cause a bit of a timing problem. I hope you didn't turn the distribitor to set timing without using a scantool, a timing light is useless on these vehicles- its been tried before. If it's a 96 vehicle, it could be distributor gear wear causing timing problems, but the only way to check is with a scantool and check the camshaft offset(cam retard on some scanners) and make sure it is within spec, 0 degrees +/- 2 degrees

[chad snyder]

i found the problem. timing isn't the problem due to the truck being self timed. it is electronically timed. anyway. while doing my tune up i or my uncle must have wiggled the wires to the cam position sensor. that caused my hesitation. but i also had a second bad sparkplug wire out of this set. but after pushing the wires back into place and replacing the wire its running like the first day outta the plant.