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in the last 2 months this has happened 3 times. i am cruising along the freeway and bam...it fells like a miss...the truck lunges and then takes back off. it lasts just a split second. the first 2 times i had cruise control on. usually travel 60-65mph. it did it again after coming home from a hunting trip and i wasn't using the cruise and was going ~75mph. no CEL light, so autozone won't even try to read codes...just left me scatch'n my head.

This is for the old '99 that the parents have now. It's got a "miss" at idle............but only after the engine has gotten up to operating temp. Cold idle is normal with no miss. It's a miss, but the computer adjusts by increasing the idle speed slightly after warm up.. Running up and down the road, she runs as good as ever. Dad says she's been averaging 19mpg most every fill up. What should I look for and check to diagnose this??? Thanks guys!!

Customer called me yesterday asked if I could tow their truck in and see if I could figure out what's wrong with it! It's a 99 2500 2wd auto with stock 24v new lift pump and reman vp44. The truck starts and lopes hard with no throttle pedal. No engine codes. Anyone have any ideas? The vp44 was put on about 4 months ago and it's been sitting at another diesel shop for 3.5 months. I don't know where to start!

My truck ultimately runs great. It has good power. I recently replaced a crankshaft position sensor and noticed the plug will need to be replaced also. However replacing the sensor only, the check engine light has not illuminated again.However recently I have started to get a miss at idle after coming to a stop. Very slight, but noticeable. You can feel it in the truck. Not similar to the hard miss the crank shaft position sensor caused. The weird thing is my AirDog 150 has also started dropping pressure pretty bad. When new it was putting out 17psi nearly constantly, about a year later it was at 15psi. Then it kept dropping, much quicker after that. Now it is at 11-12psi idle. Though it still holds over 10psi WOT. I do have the typical draw straw issues at 1/4 tank.I purchased a new filter tonight (NAPA) and plan to install it tomorrow. If the pressure does not increase a significant amount I will add some washers to increase the pressure like I have seen done on here.It seems as though the AirDog is drawing air more often than it used to. At a 1/2 tank I can draw air. I did replace the sending unit recently so I am fairly sure it is not that. Besides I can run the truck to nearly empty and as long as I don't make a quick stop it is fine.You can hear the difference in the pump noise when it draws air. It is fairly significant. I am planning on installing a draw straw in the basket to remedy the 1/4 tank issue.It is just odd to me that this miss only occurs at stop lights regardless of the tank level. Once it has idled for a bit at the light it clears out. It never happens when the engine is cold it seems. Only when warmed up and after a stop. No elevated smoke levels at all.The truck is slightly harder to start in the cold lately. I plan to replace the battery cables and probably start looking at replacement batteries...these Walmart batteries didn't last nearly as long as the Duralast I had before. The truck also on occasion cranks for a long time when parked facing down hill.Any ideas?

Ok here goes, i have my truck (in the sig) that has a noticable miss when the air temperature is below 40 deg or so. The colder it gets, the worse it is. But it only happens when the engine is under a slight load, not at idle, not at wot. The higher the chip is turned up the more noticable it is also. When the outside temp get above 50 or so I can turn the chip up as far as I want and I'll never feel it.Now my dad's truck is an '02, 6 spd, has a 70 hp bully dog chip on it also does the same thing. Not as noticable but its definitely there when it gets cold or when you throw a trailer behind it. My dad's spent a lot of time at different shops trying to figure this out. My neighbor's '01, 6 spd, edge ez, same miss. No codes on any of them.After doing a lot of reading and research a lot of ppl suggested a high pressure leak inside the head whether due to bad o-rings, crushed injector tubes, or maybe even bad injectors. Today I put new rv275 injectors in my dads truck with new tubes and o-rings as well. Felt pretty good when i test drove it this afternoon even with the trailer behind it. But i was skeptical and sure enough another terst drive this evening with a slightly colder temp confirmed it was still there. So its back to the drawing board, I'd like to get this fixed or else there's no reason to sink any more money into my truck looking for performance if its gonna keep missing. Just read on another forum to test the alternator, it might be sending a voltage spike. Luckily I'm a diesel tech in training so I have a test bench to use but I'm open to any suggestions. I figured if our 3 trucks have the same problem somebody else out there has to as well and know how to fix it. Thanks in advance for any help

Hey gangGot a guy here with an 07. He was asking me if I had ideas on his issue - details belowRuns a straight back exhaust - no DPF/muffler etcRuns a Edge Comp Race ...... on levels 1-4 whilst towing .... truck "chuggs/misses like its running lean" - his words.On Levels 5-7 its fine.Happens in OD or without OD and he doesn't think its EGT/Boost defuel (my first thought).Edge say its not the chip ......... My question is why OK on levels over 4 (like 5-7).Lets here some ideas - will pass them on - thx for help

Well if Cummins cant fix it it's doomed to fall of a clif. I took truck to cummins to let them try. Well if I had stock injectors he said they could search for leaks by pressure the system. And there stock injectors are about 500.00 each, thats what he said,I dont know. They did the usual routine stuff, hook up scanner and the usual stuff came up NOTHING. They seemed sure that the crossover tubes where leaking and one may have been. It runs a little diff. but miss is still there. Here is where I am at,new DDP 50 HP injectors, ECM,Apps,crossover tubes, cam sensor, VP Blue Chip, Head rebuilt, Starter, Alternator, water pump, thermostat & sensor, new airdog 150 with quick connects, rotors pads, drums shoes, drive shaft, ujoints, carrier bearing, kyb shocks, tires good, 2 year south bend clutch, edge ez, bd intake, gauges, 5 inch exhaust, power steer pump,ball joints, turbo the oldest thing on truck 4 years. new batts. switched out wire harrness. What you give me for it? lmao One positive thing is he is sure the head gasket not blown. lol I guess I will just drive a truck with a miss for ever. This is a real pisser.You mean this truck cant be fixed?At the end of my rope, I cant see spending another dime. 7K In 8 months.Mapp and ait the only thing not changed.

hey guys i dont no if you all remember my post bout my 2002 24 valve with the weird miss in it but just thought i would let you all no what was wrong with it. ok so the truck ended up blowing out the head gasket between 5 and 6 and on top of that the aftermarket head gasket i put on the truck not even 11,000 miles ago took number 5 piston out with it so in short the motor gets a over haul at just 154,289. thanks for everybodys help.

Ok I got new ecm and power is back and pulls great, but it still has a miss at idle, I dont know if it has miss a cruise speed or not but I do know if you put a bypass box on it it runs just fine. So where to look? I am thinking wire harness?Is wire harness two peace or single harness, in other words am I dealing with a night mare to do my self?