Brook T Posted July 5, 2018 Share Posted July 5, 2018 Hello everyone I hope someone can help me on this problem. I have a 2008 chu613 ser 1m1an07y18n002436. The truck was running fine with no issues or complaints. Then the truck shows up back at the shop with low power. I took it for a test drive and sure enough its a sick dog. Running like its missing on more than one cyl and wont even spin a tire. We changed the fuel filters and it still ran like crap. I parked it for the night and came back to it the next morning. I took it for another test and it ran great and didn't skip a beat.........until about three miles later it was like someone flipped a switch and it ran like crap again. No codes. Running again like its on 3 or 4 cyl. Checked the fuel lines for air leaks and did not find a prob. Took off fuel lines at ecm and there was no blockage or restriction. Fuel system appears to be good. Parked truck again over night and same thing the next morning. Ran liked a raped ape for 3 miles or so and then fell on its face again. What am I missing here. boost pressure is between 30-35 when running great boost pressure is 20-22 when running poor thanks in advance everyone!!!! Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/ Share on other sites More sharing options...
fjh Posted July 6, 2018 Share Posted July 6, 2018 injector cup issue is my first guess 1 Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402034 Share on other sites More sharing options...
TimberJack Posted July 11, 2018 Share Posted July 11, 2018 Did you check the plugs for oil at the ECM had one do that. Ran great until it got hot then ran like crap. I changed harness and it fixed problem Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402290 Share on other sites More sharing options...
turckster Posted July 12, 2018 Share Posted July 12, 2018 How old are the injectors? Could be a cup leakage issue or the injectors could be the problem. When it is running poor? Is there air in the fuel return? You can see it in the return port in the fuel tank, if there are bubbles coming out in the return port you have leaking cups. Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402343 Share on other sites More sharing options...
c-mac Posted July 12, 2018 Share Posted July 12, 2018 I have had the problem you've described that was a bad engine ECU but it always set a trouble code. Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402348 Share on other sites More sharing options...
staxx Posted July 13, 2018 Share Posted July 13, 2018 Check for fuel debris blockage at EECU inlet outlet and fuel base banjo fittings 👍🏁🇺🇸 Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402381 Share on other sites More sharing options...
fjh Posted July 13, 2018 Share Posted July 13, 2018 1 minute ago, staxx said: Check for fuel debris blockage at EECU inlet outlet and fuel base banjo fittings 👍🏁🇺🇸 low fuel pressure code? Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402382 Share on other sites More sharing options...
staxx Posted July 13, 2018 Share Posted July 13, 2018 You won’t necessarily get a low fuel pressure code when system is blocked . Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402383 Share on other sites More sharing options...
fjh Posted July 15, 2018 Share Posted July 15, 2018 On 7/13/2018 at 9:19 AM, staxx said: You won’t necessarily get a low fuel pressure code when system is blocked . AHH ! Good to know! Quote Link to comment https://www.bigmacktrucks.com/topic/53747-2008-mp8-falls-on-its-face/#findComment-402447 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.