olegreen Posted Friday at 07:52 PM Share Posted Friday at 07:52 PM First I would like thank everyone with help in the past. Ive been reading these forums for years with a lot of helpful information. Ive got a high rpm miss that I cant figure out and was wondering if anyone could help me out. First, I just replaced the cam, injectors, eup's and thats when I started to get the miss. Ive also changed both cam and crank sensors, fuel filters a few times and the ground bolt on the block has been cleaned. There is no lights on and it works because I had a 8-3 code when I changed the unit pumps. The miss only happens around 1700-1800 rpms, good below and above that range. Also the fuel pump has been changed to. Any help will be greatly appreciated. I really think Ive got a bad rebuilt bosch unit pump but at this point not sure. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/ Share on other sites More sharing options...
fjh Posted Friday at 08:13 PM Share Posted Friday at 08:13 PM You can’t rule out a bad injector ! If it’s not throwing a code! just saying! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594694 Share on other sites More sharing options...
olegreen Posted Friday at 08:18 PM Author Share Posted Friday at 08:18 PM The miss didnt happen until I replaced the last 4 eup's. I had 2 I installed, then the dealer had to order the last 4. Truck ran really good until I installed the last 4 eup's. Bad thing is it runs really good in every gear besides 10th, thats the only gear I can make it miss. It will pull all the way to 2000 rpms in all other gears. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594695 Share on other sites More sharing options...
Joey Mack Posted Friday at 08:31 PM Share Posted Friday at 08:31 PM What year truck and model ? Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594696 Share on other sites More sharing options...
olegreen Posted Friday at 08:40 PM Author Share Posted Friday at 08:40 PM (edited) 98 Ch 613 maxi cruise. The engine is a 2000 rated at 350 horse power, if that matters. Edited Friday at 08:47 PM by olegreen Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594697 Share on other sites More sharing options...
fjh Posted Friday at 08:57 PM Share Posted Friday at 08:57 PM You could try installing the cal codes ! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594698 Share on other sites More sharing options...
Joey Mack Posted Friday at 09:03 PM Share Posted Friday at 09:03 PM Did you inspect the EUP wires right behind them for cracks in the insulation? The wires are very strong, but the insulation will crack with age. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594700 Share on other sites More sharing options...
olegreen Posted Friday at 09:06 PM Author Share Posted Friday at 09:06 PM Dont guess I know anything about installing any cal codes. Also cylinder one had a bad spot on the wire from rubbing on the block, but all other wires seemed to be good. Also with the key on checked with a volt meter. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594701 Share on other sites More sharing options...
Joey Mack Posted Friday at 09:08 PM Share Posted Friday at 09:08 PM I think the EUP terminals are in the J-2 plug on the EECU. Do you have a pin-out diagram? I know I posted it at some point.. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594702 Share on other sites More sharing options...
olegreen Posted Friday at 09:15 PM Author Share Posted Friday at 09:15 PM No I do not have any wiring diagrams for the truck. Plus, back to the cal codes I didnt think you had to recalibrate a new eup. Its going to be hard to get this to duplicate since it only does it in high gear and high rpms. Ive got another eup coming and going to try to change them out one at a time to see if there is any changes. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594703 Share on other sites More sharing options...
Joey Mack Posted Friday at 09:26 PM Share Posted Friday at 09:26 PM You can move #3 to another hole and see if the code follows it. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594706 Share on other sites More sharing options...
olegreen Posted Saturday at 08:04 PM Author Share Posted Saturday at 08:04 PM I wish it was that easy. Since I replaced all the Eup's I dont get any codes. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594750 Share on other sites More sharing options...
Joey Mack Posted Saturday at 08:17 PM Share Posted Saturday at 08:17 PM Ok.. i thought i saw an 8-3 code posted.. youre sure that the valve adjustment is by the book ??? Not a valve overlap method ? Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594751 Share on other sites More sharing options...
olegreen Posted 9 hours ago Author Share Posted 9 hours ago Valves have been checked and adjusted 3 times since the new heads was installed. When replacing the Eup's we adjusted and checked for anything or problems under the valve cover. We adjusted the valves by putting 1-6 in the inspection cover and adjusted whichever valve was closed. Then 3-4, 2-5 and so on. Thats was how I understood you adjusted them. It just seems like its something going on with a Eup. Could the crank/rpm sensor be the problem, Ive replaced it and it didnt change much, Ive also disconnected it with the truck running and no change. The truck turns over about 4 times every time before it starts, Ive read if the crank or cam sensor was bad it wouldnt start that quick. Thanks for any and all help because Ive tried with no success on a few things. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594780 Share on other sites More sharing options...
Joey Mack Posted 9 hours ago Share Posted 9 hours ago (edited) Ok... I know I am strict about this, but here goe,s... When you bring the 1&6 timing mark to the pointer or hole in the flywheel housing, you look at the #2 exhaust valve rocker arm (the front valve rockers). If it is rocked/ open, then you are up on #1. If not, you are up on #6. Roll the engine 360, and start the valve adjustment on #1, including the .010" on the bridges. Follow the firing order. As you turn the flywheel to the next marks, it will be in order. [You will only adjust one cylinder at a time, per the firing order. it takes 2 full revolutions to end on #4 ] Edited 8 hours ago by Joey Mack More info needed Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594781 Share on other sites More sharing options...
olegreen Posted 4 hours ago Author Share Posted 4 hours ago Ok Im going to try to adjust the valves your way to see if there out of adjustment. I know we didnt adjust the bridges so we will check that also to. So if the valves are out of adjustment this could be causing my high rpm miss fire? Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594783 Share on other sites More sharing options...
Joey Mack Posted 3 hours ago Share Posted 3 hours ago Yes.. i know you have been pushing hard on this. The engine needs to be below 100 degrees when you do the valve adjustment. To check the bridges, I took a .010" feeler and trimmed both sides on the grinder to fit in the exhaust bridge, provided you have engine brakes. It works on all of the adjustable bridges. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594784 Share on other sites More sharing options...
olegreen Posted 3 hours ago Author Share Posted 3 hours ago That was my next question, my engine doesent have the spring loaded pushrod or a engine brake. So, do I still do the bridge adjustment the same way at .010? Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594785 Share on other sites More sharing options...
Joey Mack Posted 3 hours ago Share Posted 3 hours ago Yes your bridges have adjustment screws? Correct? Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594786 Share on other sites More sharing options...
olegreen Posted 3 hours ago Author Share Posted 3 hours ago I cant really remember for sure, but I think they did. So you adjust the bridges before the valves? Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594787 Share on other sites More sharing options...
Joey Mack Posted 2 hours ago Share Posted 2 hours ago Yes.. Quote Link to comment https://www.bigmacktrucks.com/topic/76579-e7-etech-high-rpm-miss/#findComment-594788 Share on other sites More sharing options...
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