Dar

Good day. Got a 2005 mack vision equipped with the aset engine. Got a 3-1 code for exhaust temp senor. At engine start up the gauge cycles with the rest of the gauges but does not move after that. I replaced the sensor, still does not work. Followed wires back into cab to the connector behind the radio, unplugged harness there and checked voltages. I am getting 1.8 volts on both pins. Anyone know what I should be seeing here for voltage? Also tested new and old sensors on the bench with heat gun and ohm meter and both seem to be operating the same. Any help would be appreciated.

Yes I changed it. Code cleared after and engine idled smooth after. But otherwise no difference. 

*90 kms per hour.

I'm sure I could find a dyno within an hour or 2 from here. However I dont think there would be any point to running it on a dyno. I know its low on power. When I'm up to Weight and conditions are not perfect I can't even make it up to 60mph. If I do get up to speed she is giving it all she has just to keep it there. I wouldn't dare try to pass someone on the highway if they were going 90 cause it would take a mile to get passed them.

It has an Eaton fuller 13 speed. Not familiar with the mack trans. Does does the eaton also utilize this torque limiter switch? 

I have been pulling the same trailers, same loads, same roads, only driver, so I know for a fact that it had more power than it does now. 

Update. Had truck at the shop. They scanned and cleared codes. 9-5 code went away and has not returned. They also checked and pressurized intake system for leaks, checked turbo and actuator operation, and calibrated. Turbo boost is good. Checked fuel pressure. Checked for exhaust restriction. Checked throttle operation.  Performed cylinder balance test. They also scanned truck while driving in low power conditions and could not find anything wrong.  Everything checks out good. Cannot make the truck smoke in any condition. Still has codes for front and rear axle temperature sensors. And a 3-1 code.  Any chance the 3-1 code could cause a derate? Any other ideas? I dont know what to do with this thing. Already bought another truck to get by. But would still like to get it fixed. 

Not loosing any coolant. Checked fuel pressure today after the filter and pump and pressure would not dip below 60psi under load. The #2 pump code remains on all the time now and when I rev the engine to 1800 under no load I can hear the engine start to miss. Think the next step will be to change that fuel pump. 

Yes the boot is sealing to the hood. Besides the pump code when it's cold out I still have the 9-5 code for compressor discharge temp. And 3-1 code for exhaust gas temp. As well as codes for front and rear drive axle temp, obviously not concerned about those codes.  As nice as it would be to get rid of these codes I dont think they are the problem here due to the fact that they have all been active for 2 years prior to this problem. 

Replaced the fan clutch. Also replaced the visible damaged turbo discharge temp sensor. Code did not go away. Does it need to be cleared with a scan tool?  Still have no power. However it is also throwing #2pump code at cold start ups. When it warms up code goes away. Will wait till the fuel tanks get emptier and hopefully drain them. 

Thanks guys. My fan clutch locked up the other day which isnt nice when it is -25 Celsius. Should have that back together tomorrow and the turbo temp sensor should be in too. Will see what that does. 

Fuel filter is brand new. 

Currently the wires are ripped off right at the sensor. So the sensor will need to be replaced first. 

Hi guys. I have a 2005 mack vision with an aset engine, been running it on the farm for a couple years. Always thought it was a bit low on power and boost was a bit high but it worked so I just kept driving. This fall however on my way home one night I could not get up to 60mph on the highway. Since then I can only get up to highway speed empty and even then the boost is continually 25-30 psi. Loaded I cannot get up to highway speed and boost rises as high as 33ish psi. There are a few codes present.

9-5.  Compressor discharge temp sensor

2-5. Front drive axle temp 

2-6. Rear drive axle temp

3-1. Exhaust temp sensor

All these codes were present before this new problem came up. Truck is fully serviced including new air filter and fuel filter. As soon as I get to town I will pick up some fittings so I can check the fuel pressure after the fuel lift pump. Also have a sensor coming for the turbo discharge temp code. If you have any suggestions I would be happy to hear. Thanks. 

I was reading a post from a few years ago of about an 03 model with what seems to be very similar problems.