I am looking at purchasing a 1999 f250 Crew Cab Long bed with the V10. It has 120,000 miles on it and has been very well taken care of and maintained. The current owner says that over the last couple of weeks it has started to start sporadically. The first time it did it was after a 30 minute drive. Parked the truck outside his garage and a hour later when he went to pull it in the garage, it wouldn't start. He called a mechanic friend that told him to trip the inertia switch. Pressed the switch, it clicked, and then the truck fired right up. Since then it has done it twice more but now instead of tripping the inertia switch he turns the key on and off 10 times and then it starts right up. Any idea what this would be? I would normally think fuel pump since cycling the key on and off would be building pressure in the system if the pump was just starting to die but the inertia switch being tripped has me confused.

The owner, who is an older gentleman, thinks or was told that quickly turning the key off and on is reseting the computer and after turning the key 8 times the locks lock and unlock and the lights flash once. Is this what it is doing? I thought turning the key on and off in multiple succession let you manually read the codes...

Any help would be appreciated. I am going to look at it this weekend, my brother-in-law looked at it for me tonight and said that it started just fine for them with no issues while he was there.

 

That sounds a lot like a fuel pump problem.
Cycling the key 8 times I believe is for the keyless entry programming and I am not really sure what the extra 2 cycles actually do..... But it definitely won't reset the inertia switch?

 

Thats what I was thinking, cycling the key was just priming the pump/system. Does the inertia switch always click when you push it or only when it needs reset?

Dang! Just looked up fuel pump prices, that is one of the most expensive fuel pumps I have ever seen! $400 for the motorcraft or about $250 for any other brand. Holy cow! Guess I am just to used to buying parts for my 94 F150....

 

Is it cranking OK or not firing OK? Two completely different problems.
If its NOT cranking OK then do some basic troubleshooting. Load test the batteries. Verify all large secondary battery cables are clean and tight from the batteries through the solenoid down to the starter. Still wont crank OK then pull the starter and have it bench tested. Grounds are very important in these and all vehicles. Find as many as you can and clean them. Spray battery protectant over all the bolts once tightened.
Cranks OK but wont fire...Look for proper fuel delivery and spark requirements.

 

It sounds like it is cranking fine just not firing. I may try to pick up a fuel pressure gauge and take with me when I look at the truck to check the pressure on the fuel rail. I also plan on running it over to Oreilly or autozone and scan the codes when I test drive it.

 

Does anyone have a preferred fuel pump brand? Other than motorcraft.....

 

I just did my fuel pump, I didn't replace the entire assembly just the pump. The assembly is quite pricey at 300 dollars or more, I used a Airtex pump which came with new strainers and so far so good. Pic of the pump inside the entire assembly.

 

Hmmm, I may have to look into that. The nice thing about replacing the entire module is it's just a plug and play. If you have time to wait for a pump to ship to you, seems like rock auto is about half the price than any of the box stores.

 

I would suggest also searching ebay and amazon once you have the exact part number you want, as you can sometimes get much better deals.

For example, I got a FP for my truck for $30+shipping, RockAuto wanted $200, local parts shops wanted over $400 for the exact same pump. Evidently, Amazon had the pump in their warehouse for a year and wanted to dump it for the cost of shipping the pump to them [as evidenced by the Fedex shipping label on the inside box].