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Discussion Starter #1
When in neutral I can rev the engine no problem. Put it in drive and it will not rev past 1400. When you drive, it is just a dead pedal. I will floor it and hardly anything happens. It does not rev, just bogs down. Felt I was going to have to get out and push it up a hill on the way home.

I have a remote start. In the past it would turn over for a second or 2 and start right up. Now it turns and turns and turns...... Acts like it lost prime. If you touch the pedal a little while turning over it will start.

I took it in to a parts store today to scan it. The only code was the OD off light. I think it was a 0751. For the last couple of weeks sometimes when you put it in gear the OD off light comes on. You put it back in park and go back to drive and it is fine.

Any ideas as to why it is bogging down?
 

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as far as the hard start; a couple of things - first is the idle set screw on the IP. i've heard as the truck gets older, it wears & loosens. if you just barely touch the pedal as it turns, it will start. or it could be a leak in the fuel system. checking fuel pressure is a good test. i just bought a fuel pressure gauge from "larry b's". there is some info on his site. also "jgeorge" has a real good right up explaining the fuel system and how to maintin it. it is either low pressure or a loose idle set screw. there's a few parts like the overflow valve-if not holding, you won't get enough pressure. you have to clean misc. parts in the system.
jon
 

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Discussion Starter #4
New fuel filter about 3 weeks ago. Did not replace the pre screen yet. The Dodge dealer looked at me like a deer in head lights when I asked for the part. The Cummins dealership is on the other side of Denver and I have not had a chance to get there yet. Air filter is K&N and was cleaned and reoiled about 2 months ago.

I contacted Larry B's about his fuel lines today and have not heard back. I am getting some fuel line from John at HCD for my veg system. Want to start plumbing it but not until I figure this out.
 

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oiled filters are not a good choice for a turbo charged engine. that filter if dry doesn't stop all the particulates, it needs the oil to catch them. the turbo is like a vacuum, it actually sucks the oil out of the filter, the intake tube will be coated w/oil. then, the grit gets past the filter, not good. ask around here, K&N is only good for the intake tube, you need a dry filter. larry b has a few very useful products for the dodge trucks - starter relay and diode to protect the fuel shut off, starter contacts, fuel pressure gauge, marine diesel hose. i have called several times (tonight i asked for help wiring my starter relay), they have been helpful. i bought all of their prducts for this truck.
jon
 

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Discussion Starter #6
The K&N came with the truck. I am getting an Amsoil dry filter from HCD. Was waiting for the next Denver get together to pick it up.
 

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Check your fuel shutdown solenoid to be sure it's pulling up all the way. Sometimes they get a little sticky, or the linkage gets off a little and they don't open up as much as they should. It causes that type of problem.
 

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Discussion Starter #8 (Edited)
Had a diesel mechanic from UPS look at it today. He thinks I have 2 problems.

1) not sure
2) maybe torque converter (I hope not)

Would a bad fuel solenoid or relay send a code?
 

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The first thing you need to do it set your idle up. That will cure the hard start.

A filter won't cause this problem unless the filter is really horrible.

If it runs ok except for the bogging down, I would look at the throttle linkage to make sure you are getting full throttle. The next thing I would look at would be the AFC. Take it off and cover the hole in the top of the rear of the injection pump with some duct tape and go for a test drive to see what happens. You don't have to disconnect anything from the AFC, just tie it up out of the way for the test drive. It should make black smoke and go pretty good if the AFC is bad. However, even with a bad AFC it should make more than 1400 RPM.

If you would like a copy of my fuel supply system writeup email me at [email protected] .
 

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Discussion Starter #10 (Edited)
I came to Cummins from a 6.5 TDI. so, I respond ...... AFC?

Joe,
I read you write up a couple of days ago when the problem started. It was very informative, thanks for taking the time to do it.
 

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I came to Cummins from a 6.5 TDI. so, I respond ...... AFC?
Look on the back of the injection pump. You will see a hex hole in a screw in the top of a rounded part. If you have my write up look on page 9 at the picture of the fuel solenoid. You can see the AFC just above it. There are four screws that hold it in place. Two of them also hold the fuel solenoid in place.
 

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Discussion Starter #12
What is the purpose of the AFC?
 

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The AFC restricts fuel until there is sufficient boost to burn in cleanly. At least that is the idea. If it fails it is like having only part throttle. The most likely cause of a failer is a broken or leaking hose to it.
 

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Discussion Starter #14
Just checked, it has been removed in the past. The factory screw was replaced with a screw that has a nice big flat blade head. I will pull it tomorrow. A little windy and chilly today in Denver.
 

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Discussion Starter #15
OK. I bumped up the idle and it starts better. I was going to go ahead and do the AFC thing. Dropped the first bolt. The washer hit the ground but the bolt did not. I cannot find it. This is when I lost my desire to work on the truck today. Think I will finish watching the draft and have an adult beverage.

Thanks for the hint on upping the idle.
 

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Discussion Starter #16
Figured it out finally. The boot on the fuel solenoid was cracked which allowed the shaft to drop to far when the truck was turned off. When the truck was turned on the shaft was off center and could not go back up.

A new boot is on order. Thanks Joe G. for the site.
 
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