About 2 weeks ago, my Durango sounded like it was running on 6 or 7 cylinders. So I install 8 plugs , as recomended in the manual, and they did'nt cure the problem.So to make a long story short, I have done the following tests on my Durango: Fuel pressure because of the rough idle, it fluctuates between 40 & 50. When I raised the RPM's just barely above idle, I had a reading of 50 psi, steady.The Throttle Position Sensor, was at 5.0.. The Idle Air Control Valve, also checked out good..I lisstened to all Fuel Injectors, and all had a good ticking associated with the speed of the motor. I still need to check the resistance on each Injector. I need to re-check my vacuum, but preliminary test show no leaks. I need to check at the manifold vacuum, not the Throttle Body where my friend had hooked up gauges 2 nights ago. After I changed the Plugs, I was focused on the coils, over each plug. I remembered one coil was missing the rubber seal around it. So , I installed a new one hoping it would fix the problem, but it did'nt. I checked the resistance on it , and it was at 0.7 ohms. The 1 that I took out of my Durango, was 1.0 ohms.Anything between 0.6 to 0.9, is good.. The charging system is all good. Had it checked about 2 weeks before, all this came down.I've still some checking to do, some more tests, but hopefully this will give you something to think about. I'm no ace mechanic, but it's got me confused. So many sensors, and whatever, all have to do with Fuel, and Air mixture.If I'm not mistaken, ALL of them have to do with it..As soon as I get some more readings, from whatever I have'nt checked, I'll post them, and hope for the best.. Thank You Guys.. These Forums can be a major help to someone, like myself. Thanks Again.. With, all this going on, I failed to mention, I have little or no power, above 20 to 25 mph. And once warmed up, it does'nt run too bad, nothing near where it should be. And it can be running ok, then all of a sudden, just start running like crap.It's been really hot these last few days. when I go out to start it, it literally half way warmed up, and it runs fairly well, decent idle.So go figure. I'll take notes as to what happens if I take it for a spin, in it. I gotta back up a little bit. I also failed to give you my scanner readings. when we first attached the scanner, we came up with, too lean left bank, too lean, right bank. a few days later, no more P0171, or P0174. Now it's giving me P0300. Misfiring. I read somewhere that a person with similiar problems, came up with P0302, which they stated meant #2 cylinder was acting up. I've checked mine a few times, and still, just P0300 or P300.. So that's it for now. Please help,anyway possible, and once again, thank you..

 

I started reading your post and got a headache about halfway through the first couple of lines so I did not go further. Please use some caps to separate your sentences. Makes it easier for us to help you if you put a little effort into making your post readable. I did see you have a Durango, so all I can recommend is that you post your question in the appropriate section for the year of Durango you have. Welcome to DF.

 

mrcohjr

I would need more information, like the year of the vehicle. I'm guessing you have a 4.7 engine? If you do have a 4.7 engine, does the engine also have a power steering switch near the power steering pump. If it does, disconnect the connector and see if the switch is leaking. The power steering fluid will leak into the wire harness and short the wires to the o2 sensors. By you helping us with the year of the vehicle, we can move your post from this section and to a section where you will get more information. I would do a dry, wet and running compression test. If you don't how to perform the three compression test. Just let me know.

 

Sometimes a crank sensor can cause a repeated P0300.

However, on a 4.7 it is very common for all this mess to be the result of a rocker or valve spring that has failed. The extra richness from the dead cylinder is the root cause of your DTCs being all over the place. Yes, even codes for the opposite bank.

Take the valve covers off and start looking.

 

thanks foranswering my SOS call. its a 2001. Ya know it says 2000 on the pink,but when i went to order that set of 8 coils for the plugs, guy said those started in 2001.anyway, i am leaking some power steering fluid. It's leaking all over everything around that ares.I just replaced the hose a few months back, and i assumed that it was leaking there again. I.ll check on that switch, you mentioned. I'll get back with an update asap. Thank's.You've convinced me, that there's still hope..

 

I have'nt checked the crank sensors, but I'm getting down to them. In fact, i'm on my way to check the power stearing switch, and i'll check the crank sensors also. As far as the compression checks go, i'm not to sure what's meant, by, wet dry, and running. But i'll check it out.. thanks, i'll reply as soon as i run these tests.. thanks again...

 

Okay, i did find alot of steering fluid in the connection of the steering switch, so i replaced it, and the oxygen sensor before the cat, converter. Now i sprayed some starting fluid in my air intake, reattached the air filter, and it started good and ran pretty smooth, until it burned it out.I've been trying to avoid the task of replacing my fuel pump unit.But earlier i said that when i checked the fuel pressure, that because of the extremely rough idle, that caused the guage to bounce, back and forth, from 40 to 50, but when i pushed on the gas just to right above idle, it ran a smooth 50..Was i wrong in giving it more gas, because if i should have left it alone, and considered that my idle, then that would point to my pump, filter, and pressure g, am i right??? i dont know how to place my post in the right section of this site, i cant figure it out. thank you again for your help.

 

I will move this to the appropriate Durango tech section, you will get more visibility there. The new member section is not the place to discuss technical problems.

 

Thank You, I appreciate it, jkeaton...