Mackpro

Being a 93 I assume it’s a VMAC 1 electronic engine However in a rare chance It could be a mechanic fuel pump engine. On all VMAC 1,2 and 3 CH/CX the speedometers are all set the same on the dip switches on the back of the speedo head. The tire size, gear ratio, trans tone wheel teeth ( usually 16) and trans top gear ratio are all changeable using the appropriate Mack software or Tech Tool. That’s how you calibrate the speedo. The new replacement speedo heads are different on the dip switches. Have you replaced the speedo head lately?

https://www.globaltransmissionsupply.com/eaton-fuller-transmission-fault-codes this works on the original Ultrashifts but not sure on the Ultrashift Plus . Most problems we saw were wiring harness/power supply , the XY shifter on top of the trans and clutch issues.

If it starts but you have to crank on it 8-10 seconds every time then it could be either of the timing sensors. When one goes bad it runs off the the other one but it’s hard to start like it’s a fuel issue. Or someone adjusted the valves wrong. As in when the flywheel pointer was on 1/6 they adjusted cylinder 1 instead of cylinder 6. Seen that happen several times.

Mdrive or Eaton Ultra shift plus?

Using Tech Tool . This is the quick test we use to check EGR system.

Buy some “Off” insect repellent with “Deet” . Spray on headlights and wipe off. Makes them like new. Our company won’t buy new headlight housings so we use Off. It must be Off with Deet though.

Won’t start working till 150 degree coolant temp. Then it’s only by request by engine ECM

Is it saying that it will derate to 5mph in a certain amount of minutes?

If you still need info . Message me your email and I can send you the complete bulletin

I saw lots of delete related fan clutch issues and hear of even more today from friends at dealerships. The huge Borg Warner Cool Logic fan clutch was a disaster and Mack kept using it till 2013-14 . Then the smaller Behr fan came out in a kit with fan blade and all needed parts included. Bad news is to make it work correctly the engine ECM needed to be reprogrammed from the dealership. The dealership contacts Mack and they make the change in the programing for that specific truck and the dealership programs the ECM with the complete program. Sadly you can’t pick and choose what you want going back in to the ECM. It’s all or nothing. Same goes for changing to a air fan clutch. Now I’m hearing that several guys who already changed to the new fan clutchs and got the correct program installed by the dealership then later got theirs deleted and now the fan clutch won’t engage because the file the delete guy put in has the old Borg Warner fan clutch programing mixed in with it. It was quite a mess for a lot of guys. Most all of these delete guys know nothing of the actual files going into the trucks . They go buy a bootleg version of Tech Tool and have some out of country 3rd party people remote in using Team Viewer and shoot the software into the truck . I have not seen it affect trucks that already had air fan clutches on them though. However never really saw very many Mack Mp truck with air fans. Mostly Fleet trucks like UPS and Kenan seemed to always use Horton air fans. Air fan on Volvos are super common.

On your oil filter stand there are 2 different oil control solenoids that control oil to the piston cooling nozzles and the oil temperature. The engine ECM controls these solinoids. No exact data on actual temps they are trying to achieve though. But 250 degrees in the summer is common. You always want your oil temp at least over 212 to boil off water /condensation.

Yes

Post it here . I’m on the phone with my old dealership 10+ times a day

I might have more info but it wil be Monday before I can get to my old paper copies of my Midliner service bulletins

It was a weird set up compared to domestic trucks. The only downside is that the air compressor ran all the time. I guess it’s the European way of doing things. I still have lots of Midliner service manuals at work.

https://n0c357rmy1njbuit2friqwu.blob.core.windows.net/documents/3UaRo$KdI0EBhB_TCH-008-012_US_001.pdf Here is a bulletin on adding a Bendix air drier to to the Midliner air system. Also Robert Bosch built the air pressure regulator that controls the tank pressure. I think the larger and last Midliners used a traditional type air compressor and governor.

From what I remember from working on Midliners at the dealership in the late 80’s and into the 90’s was that the air compressor on most Midliners pumped all the time . They had a pop off valve down by the air tanks that would open at a set tank pressure and close when pressure dropped to a certain PSI. I remember it was a pain to install a air drier. I’ll see if I can find some info on it.

The VECU code PSID40 FMI 4 is for your daytime running light module missing from the fuse panel. Lots of drivers pull them out and throw them away for some reason.

On our trucks this sometimes happens when it rains or we wash the trucks. The rubbed bare wires in the frame rails seem to short out more easily when it rains or wet.

As Onxy said the ABS and ATC system can cause dead throttle pedal issues. I thought it was only on the M-drive trans trucks but also happens on outer manual trans trucks . It was throw a Speedo sensor code as well.

The connecting rods are “ Fractured Fit” on MP engines. They freeze and break them when they are whole. So they have a rough look where the lower and upper meet.

I believe there was a service bulletin on replacing the complete tandem pump assembly when there was leakage at the tandem pump weep hole. I replaced one on an older MP with 800,000+ miles on it . Where the fuel pump bolted to the powers steering pump was chewed up inside where they connected. It was one of the few times where I pulled the injectors on a hard starting complaint and it wasn’t a cups issue.

The 04 emission MP7 in the CTP/CXP has copper injector cups and there is no upgrade to the stainless cups and updated injectors for this engine. However there are upgrades to the injector hold down yoke and bolts. There service bulletins out there for the parts and procedures

When I would go the the Mack schools in Atlanta and Chicago they had the big posters on the walls of the quad turbo engine.

Using the stalk switch on the right side of the steering column. Go through the display screen till you see “Trip Info “. Enter into the Trip Info and you will see Trip1 and Trip2 and engine hours. Go into Engine Hours . If all you see is dashes then the Engine ECM is not powering up . Possibly bad engine ecm or low voltage/bad ground to the engine ecm .