just bought a 1997 f550 crewcab longbed that has some issues, i feel like i got a good price on it, so if it seems like a dud i think i can get my money back out of it


7.3
automatic
307k miles

its main issues is a loss of power when stepping on the accelerator, if i have it about 10% throttle it drives ok, but if i increase throttle at all, its bogs to an idle. Guy that sold it to me said his buddy whom works on 7.3's suggested it is something with the injector harnesses, but could it be as simple as the TPS and pedal assembly? just got it home like 30 mins ago and havent done any real testing yet. i guess im just looking for a place to start. there is also a little smoke coming up from oil dip stick. im sure its all pretty worn, my plans are to completely restore it into my forever truck.


Is the Data Comm Connection point for an OBD2? i plugged in my scanner and no lights came on, as if it were dead.

Truck has a Bully Dog chip


Thanks folks

 

97 F350? OBD2 yes , might need more than a code tester. these engines run indefinitely in stock form, Bully dog might be the problem. I've had many 7.3 powerstrokes in different Fords and many miles , have never had a TPS issue.

I don't even bother saving them when I scrap a truck. my driver is a 97 F250 supercab 372,000 miles, it replaced my 2003 E350 clubwagon ext. runs great but body falling off 550,000 km .

 

The power for the OBDII is fused. I've had mine pop before; thought my cheap code reader died, but nope, new fuse and back in business. Check for that.

 

The injector harness is part of the valve cover "gasket". There are two pass-through plugs on each gasket that like to melt, causing reduced or no voltage to one or more injectors. Mine had this happen under 200k.

I had a beans diesel ts6 chip on my 96 and it kept eating through cam sensors. Loved the extra power, but it may have fubard my components. I was in the process of cleaning out some plugged tiny long tube on the front of the engine, after doing the valve cover harnesses, glow plugs, and a new motorcraft a.c. compressor when the shop burned down around it. Never got another diesel.

 

I thought OBDII didn't work on the diesels. I recall having to go to a shop with a Ford specific diesel reader in order to pull codes, but that was way back in 2001 so my memory could be wrong.

 

I used an SCT unit a few years ago on my 96. But as you say, things have changed since 2001

 

that one was probably a 94 model year. first year was eec4 electronics

 

The OBS powerstrokes are semi-OBD2 compliant. You have to get special PIDs to read codes or view live data. 1997 should be able to be monitored with the right scanner.

A couple things first off. when you're in park and rev the engine, does it stumble around 2k rpm? Does the fuel filter (top, middle of engine valley) look black as coal? How is your oil level?

Fuel pressure could also be an issue. You can either install a gauge or measure with a tire pressure gauge (be careful with the tire pressure gauge, itll make a mess and ruin the gauge!) You should see around 40 psi at idle, 50 psi while running down the road. There is a schraeder valve on the driver's side of the fuel bowl/regulator assembly.

TPS could also be an issue, if you end up getting access to a tool that can read live data, you can monitor throttle position as seen by the computer.

Valve cover gaskets could be an issue, but this does not seem to be the likely culprit from what I am understanding from the symptoms.