wheeler73

Also make sure to use red locktite on the cam retaining bolts and check your H rings.

There are different cam keys. If your cam was changed before it could have been put in incorrectly. Also you can get a Mack dealer to request a horsepower upgrade and find out if the injectors and or the turbo will need to be changed along with programming. Sometimes you can just get away with programming. Also you can have the dealer check if the programming is at step 12B. If it is not have them program it to step 12B as I have seen the programming help with low power.

Only if they burnt where they meet the injector. Coolant goes around the cups and if the cup leaks at the head exhaust goes into the coolant

Let us know what you find.

What did you find?

Could also be an egr cooler. Seen that more than once. Have the egr cooler checked. Also have seen injector cups, air compressors, and liners with erosion cause the issue. But if there is exhaust in the coolant I would check the egr cooler and injector cups first.

The best service truck I have drove was an Isuzu HTR with the straight 6 Duramax which is a rare find.

They still come with the gold bulldog if they have all Mack components. That is one thing Volvo did not kill yet.

Check the EECU for oil intrusion. See that alot and will cause incorrect sensor readings. You can clean the oil out of the EECU and connectors with contact cleaner. There is a bullitin to install an oil level jumper harness and replace the oil level sensor. Also have seen the oil pressure sensor and piston oil cooling pressure sensor pushing oil and there is a bullitin on a jumper harness for the oil pressure sensor. Also the bullitins state the harness does not need to be replaced. We change the harness and EECU if it is not a warranty repair as the oil wicks back out of the EECU and harness.

Harness or EECU. Do you have guided diagnostics and the breakout boxes and are there any codes?

Is this a MP7 or MP8?

Yes it probably is condensation if it is only a small amount. Replace the sensor as they go bad all the time and re-test the system. The system in my opinion is a bad design as Ford used a similar system years ago on cars and light trucks without a egr cooler and had a lot of sensor issues.

I used an old AC motor mass flow tube cut to attach the cheetah to the truck.

Here are links to youtube videos I posted for Mack engineering to see. http://m.youtube.com/watch?v=W9J9Hi-juLk and http://m.youtube.com/watch?v=H9eHF1QZ2a0. If they dont work go on you tube and search MP7 egr cooler cleaning. I am new to this so bear with me. It works on MP8 also just have to set it upma little different. It works very well. We also did this with ASET AC engines.

Is it the lower exhaust studs? If so you can take them out and clean the holes and studs and appliy silicone to them and reinstall them and see if it stops. The Mack grey silicone works the best.

Does the truck idle a lot? How many hours on it? I see a lot of sensors go bad also see the egr coolers get extremely dirty if the truck idles a lot. I have a way to clean the egr coolers on the truck. Let me know if you would like to know how?

Key on engine off it should read below 0.05 and running with the egr closed about 0.08-0.1 . That is from looking at many. Also does not matter if it is a MP7 or MP8

Check for a boost leak. I had one the other day do the same thing and the charge aircooler was split on the top row.