Inside the DREADED HPFP

[rchandler341]

I thought I would share this with the group. Especially those that are trying to understand the failure of the High Pressure Fuel Pump (CP4).

Today I had the recall Z96 done and the HPFP replaced with the "new" style. I wish I could get another new one to tear apart and see the difference. But here are a few photos of my old pump. I asked the service advisor if I could have it. At first he said absolutely not. It had to be returned to Stellantis (Chrysler-Jeep). I told him he was misinformed and on the recall paper it states that "no parts return required for this campaign". He sent me to the parts manager and he said that I can have the old pump. I found the recall letter and showed the service advisor. He said that was good to know. Don't be afraid to ask for your parts if you want them.

Once I got home I tore it apart to look for signs of failure. I have 47,994 miles on the 2021 JTRD. A year ago I pulled the metering valve on top of the pump and found metal. I did this again last December 2023 and found metal around the screen and pump housing. I also had metal in the bottom of the fuel filter housing, but it was non-ferrous and not magnetic. Once I got the pump apart the rollers and cam inside the pump are attracted to a magnet. So the metal in the fuel filter housing is from something else.

If you change your fuel filter, see metal, get a magnet and see if it attracts it. If it does that will at least tell you it could be the pump internals failing.

The pump does show some scoring and wear. I believe it should with almost 50k miles. I am hoping it is true that the recall replacement pumps have "better" hardened internals. Our workforce pickups have the HPFP replaced at 100k miles. This is mandatory in our company fleet to protect the fuel system in our diesel trucks.

Here are a few pics to show everyone the inside of our old pumps. I was happy to see the buckets did not spin and grind the cam and rollers as some failed pumps do.

EDIT: When I pulled the metering valve off the top I did not see any metal as I did before.

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[BigG]

I'm looking at the recall notice and I don't see where it says no parts return required. I would like to have this info in hand when I go in.

EDIT: found it in the repair instructions

 

[rchandler341]

I'm looking at the recall notice and I don't see where it says no parts return required. I would like to have this info in hand when I go in.

EDIT: found it in the repair instructions

Yes, left hand column on page 3/61.

This would be great to have in hand. I had a copy of it on my phone.

 

[Free2roam]

Guess I should have looked at the recall portion. I wish I had my old pump. I'd send it in to rcd

 

[Jteakus]

And still we don't know what was done to the replacement pumps to make them better.

 

[Towzone100]

I thought I would share this with the group. Especially those that are trying to understand the failure of the High Pressure Fuel Pump (CP4).

Today I had the recall Z96 done and the HPFP replaced with the "new" style. I wish I could get another new one to tear apart and see the difference. But here are a few photos of my old pump. I asked the service advisor if I could have it. At first he said absolutely not. It had to be returned to Stellantis (Chrysler-Jeep). I told him he was misinformed and on the recall paper it states that "no parts return required for this campaign". He sent me to the parts manager and he said that I can have the old pump. I found the recall letter and showed the service advisor. He said that was good to know. Don't be afraid to ask for your parts if you want them.

Once I got home I tore it apart to look for signs of failure. I have 47,994 miles on the 2021 JTRD. A year ago I pulled the metering valve on top of the pump and found metal. I did this again last December 2023 and found metal around the screen and pump housing. I also had metal in the bottom of the fuel filter housing, but it was non-ferrous and not magnetic. Once I got the pump apart the rollers and cam inside the pump are attracted to a magnet. So the metal in the fuel filter housing is from something else.

If you change your fuel filter, see metal, get a magnet and see if it attracts it. If it does that will at least tell you it could be the pump internals failing.

The pump does show some scoring and wear. I believe it should with almost 50k miles. I am hoping it is true that the recall replacement pumps have hardened internals. Our workforce pickups have the HPFP replaced at 100k miles. This is mandatory in our company fleet to protect the fuel system in our diesel trucks.

Here are a few pics to show everyone the inside of our old pumps. I was happy to see the buckets did not spin and grind the cam and rollers as some failed pumps do.

EDIT: When I pulled the metering valve off the top I did not see any metal as I did before.

Nice writeup!

 

[Rusty PW]

The cam looks like it has some scoring on it. How deep?

 

[rchandler341]

The cam looks like it has some scoring on it. How deep?

You cannot feel it with a pick or your fingernail. It is just visible. There is the same scoring on the rollers.

I am still trying to understand where the non-ferrous metal came from that I saw in my previous threads. It must be aluminum or stainless steel. But from what? Possibly the lift pump? I dunno.

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