JPR

Hello all, I am new to the site and have an wont start pickup problem. 4.9L 300 6 just quit on the highway yesterday. Got pulled home, switched the fuel filter replaced the sparkplugs and wires, will not start. Tried to spray either in the intake , still no fire. removed on plug and turned it over and noticed there is only spark when you let off the key, just as it stops turning over? Then we pulled it and it started and run good? It kind of surged up and down then quit after it warmed up and the idle slowed down. ANy info will be appreciated.
Thanks

wde3477

Welcome to the site!

Could be several things - TFI module on the side of the distributor, stator pickup inside the distributor, a worn / wobbly distributor shaft, a tired ignition coil, or the ignition switch block just to name a few.

Since it 'just quit' on you - suggest to look at the coil, TFI module, and stator pickup first, in that order. There are resistance tests that can be done so to avoid blindly replacing parts and emptying wallets.

Good luck, and let us know what you find!

JPR

Thanks for the info, truck fired right up after the coil was replaced. It does surge real low (200rpm) upto (700rpm) until it warms up.... about 30 seconds ? It never used surge as badly, I checked the voltage output and it is only 13.86volts.... mabey that is bad .... Thanks for the info its back on the road

BIG D

Welcome to the site,the idle air control solenoid on my truck caused the idle to surge or wander up & down till it got to operating temp.,swapped it out and no more surge.

Christopher Clark

I have the 5.0 for a 89 and i have issues with it starting after i turn it off. And try to restart it i know it has a new distributer but i was thinking about getting a new tfi module.