MBN C15 Fuel Resistor Made No Difference but now have 2 new codes

To "unbridge it" you just get a 6NZ file downloaded into the ECM and this works the best. Mr. Haney does these all the time and MANY guys on this site alone have had their MBN's switched to a 6NZ tune and it is like night-n-day difference.

I went the Bully Dog route on my MBN and after a few different tunes, I finally found a custom one that is getting me what I want.

 

With my fuel temp wire in place. I can see a little extra boost on hard pulls. This usually kicks on the CEL. I am running 150 ohm resistor on the truck I drive.

If I pull the resistor then I don't see any over boost and the CEL never comes on.

Mine would derate the power if the CEL came on too many times.

 

If you're getting a boost derate, I would expect that you have a 2003 or early 2004 truck with a C-15 CAT with an engine serial number that starts with MBN. You need to flash the ECM with an earlier file before you do anything to this engine. The flash upgrade will pay for itself in a month or two in fuel savings alone, plus you'll love the extra power and throttle response

 

Yes it is an MBN C15. It is not my truck, it is just assigned to me. I am pretty much stuck with bolt on stuff since the boss won't pay for computer reprograming at this time and Butler Caterpiler won't do a dang thing to try and help it out in the fuel milage department or the power department.

I think the serial number is MBN24264. I might be wrong. I had posted it here once but it seems to be gone.

 

If that's the case, you're stuck with a slug.

Bulter Cat can't do anything that would be consider tampering with the ECM, whether it increases hp or fuel mileage, their hands are tied

 

Mine is a Bridge (MBN) c15 435hp. Nobody will do anything. Everyone wants to cover their butts. Was told to change turbo,cam, etc. After hours of researching I finally figured out I need to send my ECM to Mr. Haney to be re-flashed. It is hard to pay the extra money to have it done but it sounds like it will pay for itself in short time. Mr. Haney if you could please send me your contact info so I can send you my ECM. Thanks

 

Yeap, I truely enjoy the truck other then it has less power then cats c13s. I mean, it has over 800K on it and it still looks good and I keep it looking good. I truely wish cat would get their heads out of their backsides and do something about these bridged motors. There are thousands of them on the roads still and people pissing and moaning about them all the time but cat does nothing about it when they have the ability to fix the problems and still meet the emission requirments for the date that these things were produced.

Seems their answer is to tell people to get a different truck.

The big thing is that Butler knows about these modifications and they have told me point blank that if I bring the truck in, they will check the ecm and if they find any modifications then they will reflash it back to its MBN status no matter what I bring the truck in for.

27 lbs of boost is insane for the most part, what is it going to hurt to let the boost spool up a little more?

The other thing that really gets me is that the motor can be uprated to 525 and 1850 torque but Cat seems to think that this uprate is worth 600 dollars even though it only takes an hour to do it. When it was still under warrenty the uprate was 4 times that if not even more.

Butler knows what our company does and that we pull some good loads. I mean that when loaded I am never under 105,500 lbs unless I have to deal with road restrictions and then I can still usually axle and bridge over 95,000 lbs. Butler has told me that we should have a higher hp rating in this truck. It can't hurt the economy but it might help to get the thing rolling better and beable to pull more then an ant hill without scrubbing off 20 mph.

Some of the cat gurus tell me to let it pull down to 1200 rpm. WTF. that is about 50 mph. Our speed limits are 65 on state and county roads and 75 on the interstates. Not to mention that it won't hold 1200 rpm muchless 1700 rpm or higher unless you are running perfectly flat ground and grossing less then 80,000 lbs.

If I could find a downloader and cables for less then a grand then I would buy it in a heartbeat myself. That way I could go back to stock when it has to go in the shop for something then rerate it when it comes out of the shop.

But Cat knows about these goings on. The more that cat holds out on these people, the more they will loose since people will keep shying away from anything that says Cat on it.

 

Kenworth finally uprated mine to 500hp (field setting)? but the torque setting stays the same and still only 28lbs of boost. Does not feel like 500hp, more like 435 where it started. 2 days of going back and forth with them and it still feels gutless as hell. KW only charged $500 for the uprate and I know cat wanted $600. My ECM will be going to PDI when I have the money.

 

These ECM's can be changed to the earlier 6NZ and 7CZ files also for big Hp and fuel mileage gains. The MBN uses the same part number ECM from CAT as the earlier engines

 

You definitely do not want to lug an MBN down to 1200rpm Rat especially as heavy as you are!