I like the idea of staying focused on cylinder one. I have put a stethoscope to injector 1 and heard it clicking, resistance tested it and it was the same as the rest and I sprayed soapy water on it when the engine was running to check the seal. Can an injector pass all those tests and still be malfunctioning? I am just curious. I think I will take a look at it and swap it with cylinder 3 this weekend.
I got my Diablosport inTune yesterday. I plugged it into my car and got a message that my car needed PCM calibration update. I plugged it back into my laptop then back into my car and got the update. Even though my symptoms are still there the car does seem to run smoother. This morning my car misfired on start up but it went away before I could get a data log on it. After work I connected the intune before I started the car. It misfired and threw code P0301 again. This time I got a data log on it. Now I'm trying to figure out how to view the log.
I recorded two data logs. One with the misfire and one without. There is a visible difference between the two but I don't know how to read them. I tried to attach them to this post but I'm getting an invalid file error on the upload. Does anyone know how I can get them posted?
Just when I was about to give up and go buy a toyota I came across an article about open loop and closed loop modes.
This is what I found:
Closed loop mode means the engine control module (ECM) measures the A/F (air/fuel) ratio and uses this information to maintain the A/F ratio at a certain constant value. This mode uses feedback from an (oxygen) O2 sensor to close the loop. The A/F that the system tries to maintain is 14.7 to 1. Also, it just so happens that the standard O2 sensor is most accurate at 14.7 A/F ratio, which gives a good feedback signal.
The bottom line is that the ECM control logic tries to maintain a 14.7 A/F ratio during normal conditions. Normal conditions are a fully warmed engine and other than full throttle.
Open loop mode differs from closed loop in that the O2 sensor is ignored and the engine can be managed to run at A/F ratios other than 14.7, usually richer or lower than 14.7. The ECM controls the fuel injectors without getting any feedback that the calculated fuel delivery rate actually matches what the engine received. Without feedback, the loop is open, hence the term "open loop". A good example of open loop is when the engine is first started on a cold day.
My engine runs rough when first started until the oil temp reaches about 80 degrees, open loop mode. After that the engine runs ok except for the hesitation in third gear, closed loop mode
If an injector is clogged it might not be able to supply enough fuel causing a lean condition in open loop mode. In closed loop mode that same injector might still have trouble supplying enough fuel but the fuel feedback control system will compensate once in closed mode making the symptom less noticeable.
Yesterday I swapped injectors on cylinders 1 and 3. All of the injectors and the bores they rest in had deposits on them. Cylinder one looked dry compared to the other cylinders.
This morning I cold started the car and it ran rough until it got to about 100 degrees. The symptoms are all still there though the idle seemed different when it was misfiring. Unfortunately, my car did not throw any codes. I'm hoping the misfire moved with the injector and there hasn't been enough condition logged to throw a new code.
Started my car this morning, it ran rough, threw code p0301 and didn't smooth out until it got to about 100 degrees. The misfire didn't follow the injector. That means a possible collapsed lifter or a broken valve spring. Dropping it off at the dealer tonite.
I still say that a cam position sensor and a crank sensor are going to be an easy change and cheaper than the first hour of labor at your dealer. Regardless of what people say either sensor can cause a random cylinder or single cylinder misfire... I could be wrong... but for the price its cheaper guesswork than letting a dealer throw your money at it... and even if its not... I bet its dropped a valve seat... I just don't trust em!
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First response from the dealers is that my car is misfiring because it doesn't have Mopar spark plugs in it. Really? I has the champion copper tops in it. The same dam part number that's listed on core support of the car! I don't know what I'm going to do. I can't fix stupid.
Got my car back from the dealer today. Three days and $118 later we now know that Mopar brand spark plugs are no different than the regular Champions like I told them. They are retards and I can't afford to have them experiment on my car. On the way home I picked up an Intake Air Temp sensor. We'll see. I am planning on replacing the Crankshaft Position Sensor and the Camshaft Position Sensor. They are cheap parts. When you run out of ideas, replace the cheapest stuff first.
^Dude!!! That's what I'm saying! Its frustrating as hell... I don't know why I keep posting to change the cam and crank sensors... but I feel compelled to! Lol. Like you said and I did earlier... they are going to be cheaper than starting with the stealership B.S. and I do think your going to have to do a trial and error thing with parts that can cause a misfire.... within reason.
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