richyung601 Posted November 8, 2013 Share Posted November 8, 2013 My 97 Mack CH613 shuts down while at idle and going down road. I was told it's the ECM. This is a mechanical engine so there is no ECM on the motor only in the cab on the passenger side behind the kick panel. Just for diagnosing purposes I got a ECM out of another truck put hooked it up in my truck it runs until I turn the key back. It also will take the truck down the street it does not have full engine power and it's smokes but it does not shut off so I've came up with it's the ECM!!! Any suggestions? PLEASE HELP!!! Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 9, 2013 Author Share Posted November 9, 2013 Will someone help me out here? Quote Link to comment Share on other sites More sharing options...
gearhead204 Posted November 9, 2013 Share Posted November 9, 2013 sounds like you found your problem. wrong decade of truck for my help . 1 Quote Link to comment Share on other sites More sharing options...
staxx Posted November 9, 2013 Share Posted November 9, 2013 Need to buy a new ECM and have it programmed find a used good module same as your old one or have your old one rebuilt. 1 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 9, 2013 Author Share Posted November 9, 2013 Need to buy a new ECM and have it programmed find a used good module same as your old one or have your old one rebuilt.thanks for your reply I want to make sure I'm understanding you correctly when you say module you mean the ECM correct? Quote Link to comment Share on other sites More sharing options...
staxx Posted November 9, 2013 Share Posted November 9, 2013 Yes 1 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 10, 2013 Author Share Posted November 10, 2013 YesThanks for all the help staxx!!! I have something else I noticed when I was driving the truck with the original ECM the rpm would studder around 1400 rpm do you think since the ECM is bad it will cause that? Thanks Quote Link to comment Share on other sites More sharing options...
staxx Posted November 10, 2013 Share Posted November 10, 2013 If the ECM wasn't sending a good signal to your econovance your engine timing would not work correctly , so yes 1 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 10, 2013 Author Share Posted November 10, 2013 If the ECM wasn't sending a good signal to your econovance your engine timing would not work correctly , so yesOk thanks very much!!! Quote Link to comment Share on other sites More sharing options...
boyd Posted November 11, 2013 Share Posted November 11, 2013 sorry just seen this. what i would do first is remove the tachometer sensor clean it and put back in. what it sounds like is happening is the tach sensor/tach issue may be putting the ECM in Derate mode, it is doing it because it senses the tach not working correct. 2 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 13, 2013 Author Share Posted November 13, 2013 sorry just seen this. what i would do first is remove the tachometer sensor clean it and put back in. what it sounds like is happening is the tach sensor/tach issue may be putting the ECM in Derate mode, it is doing it because it senses the tach not working correct.Thanks for the help where is the tach sensor located? Thank Quote Link to comment Share on other sites More sharing options...
boyd Posted November 15, 2013 Share Posted November 15, 2013 I believe on this model it is still going to be screwed into the engine bell, you will see a pigtail plug going to it, if you unplug the plug you can screw the sensor out of the engine bell. when you remove clean the magnet and screw back in. look at the wiring where it goes into the sensor to see if look freyed or broken. this sensor will look identical to the speedo sensor which is located on the output of the transmission, and on some models was even the same part number. the flywheel serves as the toning ring for this sensor. a year or so after this they moved this sensor to the face of the engine bell rather than on the outside diameter of the engine bell. hope this helps.. 1 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 16, 2013 Author Share Posted November 16, 2013 I believe on this model it is still going to be screwed into the engine bell, you will see a pigtail plug going to it, if you unplug the plug you can screw the sensor out of the engine bell. when you remove clean the magnet and screw back in. look at the wiring where it goes into the sensor to see if look freyed or broken. this sensor will look identical to the speedo sensor which is located on the output of the transmission, and on some models was even the same part number. the flywheel serves as the toning ring for this sensor. a year or so after this they moved this sensor to the face of the engine bell rather than on the outside diameter of the engine bell. hope this helps..This the same sensor that screws in at the fly wheel? Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 16, 2013 Author Share Posted November 16, 2013 If the ECM wasn't sending a good signal to your econovance your engine timing would not work correctly , so yesHello Staxx thanks for all the help the truck is back running great does not cut off since the new ECM has be programmed and out in. Now I have a situation with my head light since the new ECM is in all the clearance lights comes on but my headlights does not come on. They will work when you press the flash to pass button so I know the lights work. I put a fuse in fuse 16 spot #16 the lights comes on but when I turn all the lights off with switch the head lights stays on. What could cause this? Quote Link to comment Share on other sites More sharing options...
2stacksuperdog Posted November 16, 2013 Share Posted November 16, 2013 Hello Staxx thanks for all the help the truck is back running great does not cut off since the new ECM has be programmed and out in. Now I have a situation with my head light since the new ECM is in all the clearance lights comes on but my headlights does not come on. They will work when you press the flash to pass button so I know the lights work. I put a fuse in fuse 16 spot #16 the lights comes on but when I turn all the lights off with switch the head lights stays on. What could cause this?Sounds like a bad high beam switch Quote Matt Link to comment Share on other sites More sharing options...
staxx Posted November 16, 2013 Share Posted November 16, 2013 Day time running lite switch actives headlites anytime parking brake is released and fuse 16 is in. 1 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 16, 2013 Author Share Posted November 16, 2013 Day time running lite switch actives headlites anytime parking brake is released and fuse 16 is in.Ok thanks so what do you recommend to get the lights to work when I push the button in on dash to turn them on? Is there a fuse for the lights if so what # fuse? Quote Link to comment Share on other sites More sharing options...
staxx Posted November 16, 2013 Share Posted November 16, 2013 Do the lites go out when the park brake valve is pulled out and fuse 16 is in ? 1 Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 17, 2013 Author Share Posted November 17, 2013 Do the lites go out when the park brake valve is pulled out and fuse 16 is in ?No they stay on even with the key off and switch in off position. The park brake pulled out and fuse in only way to turn them off is pull fuse out. Quote Link to comment Share on other sites More sharing options...
richyung601 Posted November 19, 2013 Author Share Posted November 19, 2013 Do the lites go out when the park brake valve is pulled out and fuse 16 is in ?No they stay on even with the key off and switch in off position. The park brake pulled out and fuse in only way to turn them off is pull fuse out. Quote Link to comment Share on other sites More sharing options...
staxx Posted November 19, 2013 Share Posted November 19, 2013 Sounds like something got melted together , take a look behind the headlite dash panel and follow headlite wires back to first big connection or hood harness pivot points. Quote Link to comment Share on other sites More sharing options...
Mark Stanford Posted August 3, 2019 Share Posted August 3, 2019 O8 mack chu mp8 engine yesterday lost all power and truck shut completely down, all fluids are full, dash shows circle with x,it'll start up runs for minute half then it's like fuel shuts of,mediate shut off,no spit and rudder can someone help me out,in last 3 weeks replaced transmission, front rear end and exhaust baked and clean someone help me please!!!! Quote Link to comment Share on other sites More sharing options...
Mark Stanford Posted August 4, 2019 Share Posted August 4, 2019 20 hours ago, Mark Stanford said: O8 mack chu mp8 engine yesterday lost all power and truck shut completely down, all fluids are full, dash shows circle with x,it'll start up runs for minute half then it's like fuel shuts of,mediate shut off,no spit and rudder can someone help me out,in last 3 weeks replaced transmission, front rear end and exhaust baked and clean someone help me please!!!! Quote Link to comment Share on other sites More sharing options...
Mark Stanford Posted August 4, 2019 Share Posted August 4, 2019 I can not figure out how to see the replies Quote Link to comment Share on other sites More sharing options...
Mark Stanford Posted August 4, 2019 Share Posted August 4, 2019 25 minutes ago, Mark Stanford said: I can not figure out how to see the replies Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.