MaxxForce 7 MODs

[jacob11379]

Originally Posted by Big Dreamer

Stumbled onto this..
https://www.ebay.com/itm/DPF-emulato...EAAOSwrslaWCZw

I have it sitting in my truck right now. Guy said it would work on my coach. I bought it and had it installed and it does not work. Throws two codes.

[Caliber]

Originally Posted by Big Dreamer

Stumbled onto this..
https://www.ebay.com/itm/DPF-emulato...EAAOSwrslaWCZw

There's a big problem with that ad,,,
MaxxForce 7's where never installed in ProStar's. Maxx7 is a medium duty engine, Prostar's take a heavy duty engine.

[Rodg495]

I've driven my Maxxfoce 7 5,500 miles without a regen. I feel lucky to have this engine running smoothly and with full power. So many of you have issues with the DPF where I have not had any so far. The coach has 14,000 miles on it. Opinions on whether I should do a periodic regen every ???? miles . I drive it at about 62 mph cruising and idle it very little. I try to keep the RPMs up in slow traffic using lower gears. The computer has never asked for a regen, the regen light will flash on occasionally but does not stay on. I do use a very low dose of Cetane additive in the fuel. Regen at speed or Parked-Regen ?

[Dennis_K]

The engine does passive regens all the time while driving at speed. I assume you are referring to a forced regen, if so you can only do that when the system asks for one. It sounds like yours is working as it should. At least that is the way mine works and I assume yours is the same. In 46,000 miles I haven't had to do a forced regen on my MaxxForce 10.

[jacob11379]

Ill know more tomorrow but the mechanic's shop said they found a hose from turbo to intercooler loose and I was losing my boost pressure.

Which would make sense as to why the DFP is filling up with so much soot. I would imagine if im losing boost pressure the engine is running rich and the soot is gonna be more pronounced.

picking up coach tomorrow and taking her for a 3 hour trip so well see how she runs....

[jacob11379]

Well, I would say my trip was very nice. I didnt realize the loud noise coming from the engine was a boost leak, i just thought this engine must have a lot of velocity over the air filter or something. Now I know what a boost pressure leak sounds like.

So they fixed the leak. Which honestly I'm still dumb founded as to how this coach was being sold, going on test rides, made it through whatever testing they do when selling a used coach, while making such loud and painfully obvious noise to anybody that has driven one before.

But hey, why cry over spilled milk! At the end of the day I got it for 30k under what other coaches like this are going for and it cost me about $750 to get it fixed a couple times. Seems like I took a risk and it paid off. This time anyway!

So obvious things. NOISE, it is about 75% quieter now.....Gas mileage, I was getting 6-7 on scan gauge when I first bought the rig. 8-9 after cleaning DPF. And today it read 13.2....I'm not saying those numbers are correct but i am saying with everything equal the engine changes have made the scan gauge read way different numbers.....boost, now my numbers are running as high as 31psi and the coach is running completely different. Itll stay in low RPM with 25psi of boost where before it would fall on its face and shift. With DPF plugged it would drop to 2nd on hills. When I cleaned it I would stay in 3rd most of the time and even 4th would try to hold. Now 4th is holding pretty good.....power, if I had to guess I would say it increased about 15%, which doesn't seem like much but it really is in the way the coach is running, feeling, sounding, that is MUCH better.

I took a video a few weeks back, and I'm gonna try to go down that same road and hill when I go back home on Sunday. I'll post before and after.....

Thanks for all the help in this thread. Especially the guy that told me what his boost pressure was running on this coach. That was what I told them at shop and made them drive it as the first time they didnt.

Also, I found out that coach was made and sold in Canada, and that the parameters for my regen and DPF are the bare minimum. As well as my ECU doesn't have the ability to read low boost.

I'll attach notes

[jacob11379]

Mechanic notes...

[Ludovik]

Originally Posted by jacob11379

I have it sitting in my truck right now. Guy said it would work on my coach. I bought it and had it installed and it does not work. Throws two codes.

We have provided troubleshooting but it seems there was another issue.
Make sure that MAP and Inlet temp sensor are working and have good voltage on them.