Buddy of mine has an 88 work truck, 302 5.0 EFI. Idles fine, but going 55 seems to run rough like its missing. He has tuned it up and what not, we r thinking either the timing or fuel filter needs to be changed. Also, Takes a bit to start up but starts fine once "warmed up".

If it is the timing, is there a good write up on how to do this? I did search through the site and got most of the info, just not sure exactly how to do the timing.

Any help appreciated!

 

Haynes has the write up on checking and adjusting timing. It's in Chapter five, section 10 of the book I have. It's worth the investment of $20. I've got the same vehicle and it's 10 degrees below top dead center. This # can be found under the hood on the "vehicle emissions control information" label. My label is stuck to the top of the air filter housing.

The book says the fuel filter should be changed every 15,000 miles.

Hard cold starts can be caused by a number of different things. Haynes details five items to be checked initially beginning with a battery check and faults in the fuel or electrical system. When was the last time the throttle body and upper intake manifold were cleaned?

He's on the right track with a tune up. If the other tune up items haven't been done then it's a good idea to continue with that line of thinking. It needs to be done and can only help matters. (fuel filter, air filter, throttle body cleaning, oxygen sensors, cap, rotor, plugs, wires, etc.) None of it is too expensive. Once he's up to speed on the maintenance items you can move on down the trouble shooting line.

I'm very happy with my EFI 302. It's got 179,000 miles and running well.

1988 F150 SuperCab Short Bed
5.0 302 V8 EFI 4 X 2

 

Yep hes got the same truck... LoL Awesome... My pop had a 92 that I inherited... Regret selling it eveytime I see a truck like his... Anyway... He found it... Had plugs that the parts store said were pre gapped and really weren't... needed .044" and they were pre gapped at 54-56... That fixed it, but I still told him to do the fuel filter which looks like a pain in the rear on that truck...

 

That filter is on the inside of the left frame rail adjacent to the transmission. I don't think it requires any special tools. Relieve the pressure at the frame rail and trip the inertia switch prior to removal.