My 351 ran well most of the time but seemed to struggle on hills at highway speeds, ball-less and some hesitation. I tried a whole bunch of things, but solved it by rerouting the sparkplug wires away from each other. Apparently, I was getting a bit of crossfire.

Not sure how that would relate to the poor fuel economy though. Are you running stock size tires. Bigger tires and a speedo that hasn't been corrected for it could cause poor fuel economy calculations.

 

Your truck should display 3 digit codes. The 33 is the all clear 111 - 111.

 

OK, so I think I have a better reading on it now

I think its 11 during the first part which would make sense since the light is not on right now

Then its 72 & 73

During the running test its
72
63 (maybe 53)

then it flashes 2 at the end which makes no sense

 

FWIW my '92 F350 4x4 w/5.8L and E4OD is a gutless wonder. I get around 12 MPG highway if I run unloaded at 65 MPH. Around town mileage varies from 6-8. I have done a complete tuneup with new filters, MSD cap/rotor/coil, new Autolite plugs gapped @.055", Bassani 3" y-pipe, Magnaflow 3" muffler and a 3" tailpipe. When I did the exhaust I also replaced the O2.

I have replaced yards of vacuum tubing and a few vacuum reservoirs. Add in a new EGR, EVR and PCV valve. I have no error codes or other drivability problems. The stock 3.55 gears and 32" tires are it's worst enemy. The overall diameter is close to the stock size, only a few inches wider.

This thing has only so much power to give. All the parts I put on it have helped very well as a package. Nothing else will make a difference until I change gears, build a better motor and/or go forced induction. Best advice is to take care of any code issue you may have. Then settle for what you have or spend some more $$.

 

How about a base timing bump to something like 14 BTDC?

 

rla2005 I appreciate the notes, I guess Im stubborn but I refuse to believe that back in 1993 a guy would buy this 5.8L truck for 20/30k new and not even be able to tow q small fishing boat above 40mph on an incline. I believe I am getting closer to figuring it out because it is running stronger on flats unloaded. I am going to try what ymeski56 said with the timing, but I cant get to a timing light until Wed or thursday then i will post feedback. I went and got a new accelle cap and rotor assembly and all new plugs(again). Also someone asked and I run 87 octane.

 

I knew there was something I missed....I bumped the timing to ~12. I plan to try some more when it gets warmer.

 

Don't forget you have to have the spout plug removed when checking & adjusting base timing! Just as important, replace it afterwards, or no ECU advance will be added.

 

OK, so
I have the
11 All clear
then key on engine off
72 and 73

Key on running
172
632

632 seems to do with cycling the tranny after the 4 flashes but before I need to throttle after the single flash, but everytime I do this it never asks me to go to WOT or starts the diagnostic flashes.

 

14's better. 16 BTDC is the sweet spot, if your engine will tolerate it w/o ping. I highly recommend Mororcraft stock copper cores for timing bumps. Double Platinums will not allow as much advance & stocks are safer, designed to fail prior to possible piston damage, if your hard of hearing when it comes to PING! Cleaning the Combustion chambers w/ Seafoam (through the power brake Vac hose while at warm idle, shut down for 15 min, then rev out the crap) is almost a priority first, as deposits are usually the reason engines disagree w/ the Mod.

 

I have standard Autolite copper core plugs. I've had good luck with them in many of my Fords. Timing was set with SPOUT pulled, then returned to it's normal service position. I started out with 12 BTDC when the weather was cooler. I am waiting for some normal 80+ summer weather trying to sneak up a few more degrees.

 

I know you know about SPOUT plugs, that comment was for 92F250HD, in case it was his first time. Autolite C/C's will work fine too!

 

By spout plug do you mean the little gray cap in the harness over by the OBD1 test ports?

 

If that's where your TFI module is also.

 

My bad.....