The cylinders varie from cold start tocold start. misses and carries on for ten to twenty minutes but does not smoke at all then if you stomp on it will come out of it an run real strong all day with plenty of power an fuel economy. have replaced all injectors and under valve covers wiring harnesses with no change I have put up with this for 50,000 miles-190,000 on vehicle now. Various diagnostics have been run on it an all they tell me is it misses when cold then its ok. also all glow plugs have been tested an replaced. they all work great or it would not start at all. It starts right up even in cold weather with no smoke but a severe miss. A REAL MYSTERY. PLEASE HELP.
I am not familiar with the model but from your description it is a common rail diesel. You omitted to mention whether it is direct injection or indirect.
Given if the engine and cold start and injection equipment are all serviceable the engine would spring into life on all cylinders almost simultaneously.
Assuming the injection equipment and the cold start is serviceable, the only thing that will then prevent a cylinder firing is an engine problem, namely a lack of compression.
It would be interesting to know if the misfire is always the same cylinders and if those are on the same bank? If the engine is an indirect type the cylinders are particularly sensitive and prone to not starting if things aren't perfect or almost perfect. The heat loss from this design is great and so a cold start aid is necessary even in relatively mild weather. Direct injection is much more forgiving and tolerant of imperfections and good examples will start well down to freezing point without aid from a cold start.
A compression test and a cylinder efficiency test on a cold engine would indicate the condition of the cylinders and if they are found to be equal within a very small margin it can be assumed the problem lies elsewhere and the fuel and cold start systems should be revisited.
There is incidentally, a condition known as tappet jacking. With a cold engine the oil pressure can be abnormally high during and after starting so it is possible for the hydraulic lifters to jack the valves from the seats if the springs are just a little weak. Conversely while an engine stands overnight the valve spring pressure on those valves left open when the engine stops can squeeze the oil from the lifters so on starting those valves open significantly less than the others. While not exactly causing a misfire it does result in a cylinder that is temporarily producing less power. This condition does not always produce the expected noise and it can take a significant amount of time to rectify itself.
Food for thought...
You have a powerstroke engine in a 2005 Dakota? That must have been a nightmare getting set up.
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SOURCE: Backfire loss of power
I would figure that it's the brain. I have had to replace mine 2 times. It backfires and misses and stalls and sometimes runs great. You can also check to see if the conections to the brain are all firmly attached. I guess it is aproblem with this year of dakota and brains ar hard to find.
SOURCE: 2002 stratus stuttering on takeoff and while driving
you can have the engine light checked at auto zone or advance auto but check the cam position sensor
SOURCE: runs about thirty miles then acts like flooded or exhaust plugged
try checking your cadlist convert on your exhusted
SOURCE: 1997 ram 1500 5.9 wont rev past 2000 rpm
well, the timing on your ram is computer controlled. is the truck in drive when this mis-fire occurs? or at idle? youve addressed part of your ignition w/the cap-rotor-plug wires. did you examine the old cap for carbon tracking? did you install the rotor properly? i know on my '97 ram the dist is feakin' buried in the engine it would be easy to rotate the rotor while installing/removing it so the timing mark is off. does your engine have the right plugs installed? your plug wires follow the correct firing order with your dist? you did not mention anything about your ignition coil. here is how to safely remove and check your ignition coil. disconnect battery-at the coil disconnect the lead wire (TOP) and primary (BOTTOM) from the coil. label your wires, or take a pic of your ign coil before you remove it so if you forget where the wires go, you have reference point. remove mounting screws and remove coil. clean coil to remove rust/dirt and wipe coil terminals off. inspect case for damage. with a multi-meter, check coil primary resistance by selecting ohm's and then place + and - leads on the pos/neg terminals on the coil, dodge used 2 brands of coils either a "diamond" or a "denso" primary resistance for the diamond mfr'd coil will be between 0.97-1.18 ohms. secondary resistance 11,300-15,300 ohms. Denso primary resistance 0.95-1.20 secondary resistance of 11,300-13,300 ohms. to measure secondary resistance place one of the leads to one the primary terminals and the other lead attatch to the large center terminal. compare your readings to the above values. if your readings are not within range of the above values, your problem is the ignition coil. other causes you may consider is faulty: speed sensor, throttle pos sensor/trans issues like bad pressure solenoid (actuates gear changes) a fault in your overdrive system. hope i have helped!
SOURCE: 96 dodge intrepid 3.5 seems timing is to slow starts & runs
Replace your catalytic converter. Check your exhaust manifold for leaks aswell
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