dieselfuel007 Posted July 7 Share Posted July 7 We have a 07 granite with a 370 and t310mr trans it’s had a random miss that’s been getting worse you run it hard loaded in town that’s when it’s the worst when it cools down it’s not as noticeable sometimes it even nearly goes away almost instantly we’ve changed nozzles and eups cleaned engine grounds it’s been at the dealer they can’t figure it out I have a 05 granite that has the same engine and transmission can I swap ecms to see if that helps or does anyone have any other ideas Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 7 Share Posted July 7 does it do it when idleing? if so, does the RPM's go from 650 to 625 and back again? Hook a fuel pressure gauge to it and see if there is a pressure change when the miss happens. Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted July 7 Author Share Posted July 7 Yes it’s got a miss when idling it doesn’t really come and go idling it’s kind of like if you take off at one stop light it’s missing really bad next one not so much it’s obviously down on power as well it really seems electrical to me just because it’s intermittent but seems to be more frequent than it used to be where is the best place to check fuel pressure Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 7 Share Posted July 7 when you had the EUP's out, did you notice any cracks in the wires? they are proned to crack and rub againt the block. you can un hook the EUP wires, and un plug the EECU and check the EUP wires with DVOM for a short to ground on the block. Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted July 8 Author Share Posted July 8 Dealer did all the work with the eups but I will take a look at the wires 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 they should have known to tell you what i said.... just sayin... Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted July 9 Author Share Posted July 9 If these wires are grounding out at the eups would there be a lightning bolt on the because it doesn’t have one on it was the dealer for three weeks trying to find it Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 so there werent any 8-? codes???? Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted July 9 Author Share Posted July 9 No that’s what’s strange I don’t recall a lightning bolt coming on in the truck when it does this I’d don’t have a lot of knowledge of how the system does it’s diagnostics if it had a bad wire or a wire grounding out should I have a lightning bolt? Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 not always a code right away, but a 9-2 code is a bad ground code... its called ''power reset without the key'' as if the batteries were unhooked while it was running or cranking.. my point is... if you use that buletin and check all the grounds, it fix this issue.. I never tell someone to replace EUP's wire hareness, or ECM's, because in my experience it's been a bad wire, or connection.. it sucks to spend 5 G's on nothing.. 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 9-2 code.pdf Quote Link to comment Share on other sites More sharing options...
Adkat Posted July 9 Share Posted July 9 Does the lightning bolt⚡ come on when you cycle the ignition to on? 1 Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted July 9 Author Share Posted July 9 I will clean these grounds I’ve cleaned the engine ground before but I will do it again where is this ground breaker in the bulletin and the ones on the dash?if there isn’t a lightning bolt on the dash will it retrieve this code if I use the cruise control or do they have to be active to do that? Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 the lightning bolt needs to be on to retrieve the codes with the cruise buttons.. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 Do you have one of these?/ Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted July 9 Author Share Posted July 9 No I don’t have a code reader for Mack Quote Link to comment Share on other sites More sharing options...
Adkat Posted July 9 Share Posted July 9 @dieselfuel007 does the lightning bolt light up as you turn the key on when the ECM is doing its self test? Ground breaker, not sure on your granites over there, but should be on firewall or EPDM. @Joey Mack will know where Have to pull cluster and dash panel out to get to dash grounds 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 AdKat is right.. Quote Link to comment Share on other sites More sharing options...
JoeH Posted July 9 Share Posted July 9 While idling & missing, press a flathead screwdriver firmly against each injector line, roughly an inch above the EUP connection. You should feel injection pulses. If one of them isn't pulsing then that's your problem cylinder. Second test is a cylinder cut out test: individually pull a wire off each EUP, one at a time, reinstall each wire as you go. Don't back wire screws out all the way, they're not designed to come all the way out. The wire end is egg shaped to slide off a loosened screw. You'll get a spark as you take the wire off. You're listening for which EUP cutout affects the idle the least. Another thing to check: valves have Rotators. Pull your valve covers and look for missing rotators in the valve caps. Joey will know better than me what these look for. If all this checks out then you need to inspect your camshaft for a bad lifter that maybe ate a lobe on your camshaft. I just had $18,000 of work done on my 2003 AI350, which had some combination of all of these failures including injector nozzle. Only part of the above I dodged was camshaft, but I did have 2 failing lifters and 3 bad EUPs. 2 broken EUP springs and 1 failing solenoid in an EUP. 2 Quote Link to comment Share on other sites More sharing options...
JoeH Posted July 9 Share Posted July 9 Any time an EUP is removed, remove it's lifter as well. Costs nothing to lift it out and check the roller and do a visual on the cam lobe. The axle shifted on one of mine, resulting in the axle only being held by one side. 1 Quote Link to comment Share on other sites More sharing options...
JoeH Posted July 9 Share Posted July 9 I found the screwdriver/injection pulse test in Mack literature. Sounds "batty" til you try it. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted July 9 Share Posted July 9 Not crazy at all. I put a finger on the lines and can feel the pulsing.. Quote Link to comment Share on other sites More sharing options...
dieselfuel007 Posted Friday at 11:57 PM Author Share Posted Friday at 11:57 PM Well I’ve finally had some time in the shop swapped ecm with another truck and put the ecm from the truck with the miss in the other truck neither truck run different with the others ecm checked fuel pressure it seemed good at idle and at 1600 while I was at my dealer I picked up a fuel pressure regulator/check valve instantly upon start up could tell it run a lot smoother it was on the job today driver said its way better thanks for all the help 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted Saturday at 12:04 AM Share Posted Saturday at 12:04 AM That's what I'mtalkin' bout.. Those regulators will F-U-up... I preach them often.. Good deal. Jojo Quote Link to comment Share on other sites More sharing options...
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