F-650 with CAT problem

Tow Master

Tow Master

Diesel Dude
Joined
May 10, 2009
Messages
89
Hey all!

I was wondering if anyone had any experiance with working on a CAT? My 2004 F-650 Rollback with 190,000 miles has been acting up. When you go to start it it cranks a long time about 10-15 seconds then starts like its cold. When it is running and idling it has alot of diesel knock. I tried chaning the fuel filter and that didnt help. The other day I was loading a car at my shop then pulled out onto the road and it wouldnt accelerate to speed like the fuel pedal wasnt hooked up. I turned around and drove it later and it runs fine going down the road but idles like crap.

It just started doing it the other day and Im not sure what to do. I had my friend check it with a scanner and he said the injectors look ok? He said some of them have problems with the pick up in the main tank cranking and getting air in the system.

Anyone have any ideas or anything to look at? I dont want to drive it now and have it break down then pay to get it towed back. Thanks for your help! Jason :Cheer:
 
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you could have some poor quality fuel with the way diesel is anymore its a very good possibility
 
Wow thanks for the quick reply! :D

Its possible! I always get fuel at the same place. Its the only place in town that has pumps to load a dual tank truck. The do a lot of big rigs and go through alot of fuel but anythings possible.
 
What kind of CAT engine is it?? C7. C9, 3126??? Because if its a HEUI system then you should check your ICP sensor that is located on the head. Those like to go bad. what kind of scanner was your buddy using? was he able to view active codes on the engine alone?
 
Oops.. I think its a C-7 Whats a HEUI system and how can you tell if the ICP sensor whent bad?

It was a QTC scanner but I think he just checked it for codes, and checked the injectors.

Im just not to familiar with medium duty trucks and I owned this truck for a year with no problems.
 
HEUI is the same fuel injection system powerstrokes use: Hydraulically actuated Electonically controlled Unit Injectors, i can almost guarantee its the C-7, i havent seen a 3126 in any medium duty truck newer than a 99, but thats just me
 
You would have to check it by either back probing the sensor or reading the voltage via data link... its located on the head on the driverside kinda in towards the front, but its right on top... Its a 3 wire senor.
 
Update!

I took it to CAT yesterday and they hooked it up to the computer. They did some sort of test and showed me they tried to raise the idle and when they raised the idle numbers for a sensor where suppose to match up but they didnt?

They say it means in needs the HEUI pump. They said they think the driver went bad and its internal on my motor so I need to buy the entire $1100 pump :doh:

They said they were 90% sure thats what it is. Im real glad I tool it there they were great guys. I was just checking to see if there was a way to check the pump or driver to find out if its bad for sure.

Thanks for everyones help! Jason
 
Ya C7 are the smallest cat truck engines out there...Not anymore tho because cat pulled out of the over the road truck engines, i think starting back in early 2009
 
Tow Master said:
I took it to CAT yesterday and they hooked it up to the computer. They did some sort of test and showed me they tried to raise the idle and when they raised the idle numbers for a sensor where suppose to match up but they didnt?

They say it means in needs the HEUI pump. They said they think the driver went bad and its internal on my motor so I need to buy the entire $1100 pump :doh:

They said they were 90% sure thats what it is. Im real glad I tool it there they were great guys. I was just checking to see if there was a way to check the pump or driver to find out if its bad for sure.

Thanks for everyones help! Jason
Click to expand...
WHered you take it Jason, clevlend bros, Kenworth?
 
Tow Master said:
Hey all!

I was wondering if anyone had any experiance with working on a CAT? My 2004 F-650 Rollback with 190,000 miles has been acting up. When you go to start it it cranks a long time about 10-15 seconds then starts like its cold. When it is running and idling it has alot of diesel knock. I tried chaning the fuel filter and that didnt help. The other day I was loading a car at my shop then pulled out onto the road and it wouldnt accelerate to speed like the fuel pedal wasnt hooked up. I turned around and drove it later and it runs fine going down the road but idles like crap.

It just started doing it the other day and Im not sure what to do. I had my friend check it with a scanner and he said the injectors look ok? He said some of them have problems with the pick up in the main tank cranking and getting air in the system.

Anyone have any ideas or anything to look at? I dont want to drive it now and have it break down then pay to get it towed back. Thanks for your help! Jason :Cheer:
Click to expand...
On the back of the cylinder head there is a fuel pressure relief/check valve in the fuel return. They get debris in them(usually little bits of injector o-ring) and stick open a little. Don't bother trying to clean it, it's better to just replace it and be done.:Cheer:
 
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