bulldog52 Posted July 30, 2016 Share Posted July 30, 2016 We have three 2007 Granites with mp7 engines and are constantly dealing with sensor issues. Exhaust temp with one and oil pressure and temp with the other two. We've tried the "updated" sensors and it's still a problem. With one it'll cause an intermittent shutdown and the other two the gauges dance around. No answer from the dealer other than try another sensor or bring it in so we can throw parts at it. Has anyone come up with a fix for this? Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/ Share on other sites More sharing options...
turckster Posted July 31, 2016 Share Posted July 31, 2016 Is the engine harness ok? If the old sensors pushed oil into the harness, has the oil contamination made it to the eecu terminals? If so the oil contamination can cause electrical glitches. The only good cure is a new engine harness. A temporary fix is to clean out the oil contamination with electrical contact cleaner but the oil will migrate back. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-340949 Share on other sites More sharing options...
Macktech689 Posted July 31, 2016 Share Posted July 31, 2016 Mack knows the exhaust temp sensors are unreliable and has come up with a delete kit to remove it. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-340960 Share on other sites More sharing options...
bulldog52 Posted July 31, 2016 Author Share Posted July 31, 2016 So if you delete the factory sensor, do you install an aftermarket sensor and gauge? I'm guessing if you delete it then you also have to reflash the ECM? Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-340975 Share on other sites More sharing options...
Macktech689 Posted July 31, 2016 Share Posted July 31, 2016 Installing an aftermarket sensor should be done but is not part of Mack's "fix", that's something you'll have to do. Reprogramming of the instrument cluster is done as part of the "fix" 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-340976 Share on other sites More sharing options...
bulldog52 Posted July 31, 2016 Author Share Posted July 31, 2016 So the "fix" is to eliminate the exhaust temp sensor altogether?!? That doesn't make much sense. What about the rest of the sensors? Has anyone figured out how to keep oil from getting into the harnesses? Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-340989 Share on other sites More sharing options...
fjh Posted August 1, 2016 Share Posted August 1, 2016 Problem is there are several places and it aint cheap to replace! Remove the gasket from the pan level sensor plug is one fix! However, it can come from the injector harness, it can come from any of the oil pressure sensors monitoring the engine! One fix would be a 2 piece harness adding yet more places for moisture into the harness. Catch 22! A connector at the valve cover would be nice but good luck with that! They aint doin that anytime soon! They are to busy bandaiding the fuel system! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-341011 Share on other sites More sharing options...
bulldog52 Posted August 1, 2016 Author Share Posted August 1, 2016 Yeah we've already replaced one injector harness on one of the Granite tractors and installed the two piece oil level sensor harness or pressure harness, can't remember which one but we're still getting erratic readings. That tractor just has the gauges bouncing around but never a shutdown situation. The other tractor sometimes has the shutdown light and beeper going off all day causing the driver to go crazy and sometimes it shuts it down entirely. Sent from my XT1565 using Tapatalk Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-341022 Share on other sites More sharing options...
Ian liburd Posted June 14, 2023 Share Posted June 14, 2023 i have a mack granite with@an mp7 engine. the electronic malfunction light is on and when i accelerate it goes and comes back. the problem is the engine brake cuts in and stops before the light comes back on also theres a little hessitation when accelerating it would hace no power on pedal for like 6~8 section and in that time it blows a lot of nlack smoke. Quote Link to comment https://www.bigmacktrucks.com/topic/46274-mp7-sensor-issues/#findComment-532954 Share on other sites More sharing options...
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