93 F450 Diesel running bad

[FB71]

you are very welcome. I'm glad I could help you get it back up and running for minimum cost!!

[sc72]

OK so here is the bottom line with the problems with the 92 7.3 Diesel not running good. FB71 you are 100% right it was a fuel contamination problem. The station were we normaly buy our fuel, some how got gas mixed in with their Diesel fuel, all is good now, replace the fuel filter, all new fuel lines and inline filters. The truck is back to making money and i'm quite happy the repair bill was a small one. Thanks to your expert advise we were able to fix the problem our selves and keep the cost to a minimum. Thank you

[easywind]

As an owner of an obs 97 I've found the two main starting issues to be, A)battery power and B)clean oil and the proper amount.
Batteries need to be fully charged. Oil need to be clean and full including the HPOP.

[Larry Hampton]

Sorry, his is an IDI, a '94 model. It was the lift pump, his bill was $425, $125 for towing and $300 for the lift pump, labor, they drained the tanks of the 4 year old fuel.

[sc72]

I just realized I misread the OP. I thought it said the truck was a 94. I see its a 92. OK, so to revise my first question; 92 could have been either a 7.3L IDI or DI. IDI uses a conventional injection pump, the DI uses the CAT HEUI injection system. Diagnostics for each are significantly different. Can you tell which you have?

Yes Sir, it is a 92 the position of the injecters would lead me to think it is a IDI, the injecters stand straight up, i did check the fuel filters [ cut the filters apart ] nothing extra in the pleats, i pulled the injecters, some were dry and the rest were wet and had carbon deposits, i'm probably wrong with my terms here but, the pintals or the sharp ends protruding from the injecters are still sharp. I pulled the fuel line loose at the fuel filter and had plenty of fuel at that point.

[FB71]

I just realized I misread the OP. I thought it said the truck was a 94. I see its a 92. OK, so to revise my first question; 92 could have been either a 7.3L IDI or DI. IDI uses a conventional injection pump, the DI uses the CAT HEUI injection system. Diagnostics for each are significantly different. Can you tell which you have?

[Zanzer]

ok, first question; 7.3 DI or DIT? (no turbo, or turbo?)

second; do you have access to a scan tool? Not a code reader, but a real scan tool.

it could be a fuel issue (as stated), a high pressure issue, or an electronic issue.

I repaired and taught PowerStroke 7.3L DIT repair for many years at Ford. I'll be glad to try and help.

Ok, Jim's on board so I'm totally subscribing to this thread now

Mine is a 7.3 Turbo. I don't have a true scan tool, just a reader I was thinking maybe my SCT Xcalibrator interfaced with my laptop but I'm not sure if it has diesel capability.


Per Shadetree's question - I service the truck religiously with Motorcraft filters and Rotella oil.


I'll be the first to admit that diesels aren't my thing. I've worked on the simple stuff like services, glow plugs, injector pumps, etc but my knowledge is still way behind what I know about gasoline engines IMO.

[sc72]

ok, first question; 7.3 DI or DIT? (no turbo, or turbo?)

second; do you have access to a scan tool? Not a code reader, but a real scan tool.

it could be a fuel issue (as stated), a high pressure issue, or an electronic issue.

I repaired and taught PowerStroke 7.3L DIT repair for many years at Ford. I'll be glad to try and help.

Thank you sir, i'm headed out to the truck now, crap all i have access to is a code reader and this truck is a OBD1 and it is a DI Engine. I'll be back later.

[sc72]

Well this is going to sound stupid but ill explain ... when is the last time you changed the oil ?? If its the 7.3 the inj work off oil pressure . Fb71 correct me if I'm wrong but a 93 should be the 7.3 . I'm not saying that's your fix just something to try. I have had the same problem before on high mileage engines mostly .

OK. note taken, will check records. might just change the oil anyway.

[Larry Hampton]

It was the lift pump. He took it to a diesel shop, $400 for the lift pump, labor and 2 gallons of diesel is what his wife told me, he's in a meeting.

His is a DIT too.

[shadetree]

Well this is going to sound stupid but ill explain ... when is the last time you changed the oil ?? If its the 7.3 the inj work off oil pressure . Fb71 correct me if I'm wrong but a 93 should be the 7.3 . I'm not saying that's your fix just something to try. I have had the same problem before on high mileage engines mostly .

[sc72]

ok, first question; 7.3 DI or DIT? (no turbo, or turbo?)

second; do you have access to a scan tool? Not a code reader, but a real scan tool.

it could be a fuel issue (as stated), a high pressure issue, or an electronic issue.

I repaired and taught PowerStroke 7.3L DIT repair for many years at Ford. I'll be glad to try and help.

It's a DI engine, please excuse me i have to leave for a little bit, i'll get back to you in a little bit. Thanks

[sc72]

Around here, in Balto/DC traffic, the F450 JerrDan rollbacks usually average 8-10. 12-14 out in the burbs and rural areas.

OK. thanks then i'm not far off if any.

[sc72]

I have a 95 with a similar issue. I would be going through the gears and it would sometimes fall on it's face from one gear to another. I thought it was a fuel issue because I could press the clutch and rev it a few times and it would clear up. I changed all the filters and ran Diesel Kleen through it religiously but it still did it. Then one day it wouldn't take any fuel at all. It idled fine but when you hit the accelerator it was like it wasn't connected to anything. I think I've got mine somewhat pinpointed down to the drive by wire throttle set-up. After messing with the throttle driver a little it finally cleared up enough to get it to move again but it still acts up from time to time. I can't comment as to whether replacing the switch cleared it up because I haven't been able to locate a replacement yet. It's just something for you to consider while troubleshooting the issue.


EDIT: I'm curious to find out about the lift pump too. Thanks for the heads up Larry

Zanzer,i'll start with the lift pump tonight, were would be the best place to split the fuel delivery after the pump and what should the gallons per minute be for a good working pump. I will look into your other suggestions also.

[FB71]

hey i'm getting 10 mpg whats the average with these. Thanks

Around here, in Balto/DC traffic, the F450 JerrDan rollbacks usually average 8-10. 12-14 out in the burbs and rural areas.