Guys,

I was reading another post that i found on the site an it sounds alot like my problem. I have listed below for your reference. I have a few differences, but mostly the same. Here it is. http://autoforums.carjunky.com/...njector_hell_P50742/ .


Before i go any further i should tell you the circustance with which this started. I stopped and filled up my car at the gas station, and started on an hour long trip. The car started missing horably and then speedometer and the temperature guage started acting eratically. Then the alternator light came on. I pulled over and turned off the car. After looking at everything under the hood, i decided to see what would happen i f irestarted the car. I started with no problem, no lights or anthing except the check engine light. The speedometer and stuff worked fine. I had to do this two or 3 times to get back home. When i got home, i pulled the codes off the compter and got the following codes. P-0106, P-0123, P-1478, and P-168.4. I replaced the map sensor, cleared the codes and none of those codes reappeard and the check engine light was off. I drove to town the next day. The car drove great. Problem solved i thought. Then the missing started on my way back home. None of those codes ever returned except the last and that is related to disconnecting the battery.


When i got back home i ready the codes, expecting to see the same codes and to find out the map sensor was not the problem at all. This time i got the P0204 code. If the vehicle runs long enough, the p0304 will come on as well. I have replace the spark plugs and wires. I have not done everything that was done in the previous post, but i have taken it apart several times and to no avail. My engine misses all the time. If i clear the code, it comes back immediately. I have looked for a visual damaged area on the wiring harness, but have not found one yet. To verify that it was not the injector, i swapped the #4 and #6 injectors and still have the same problem. I disconnected the #6 injector and started the car. The voltage on this injector read 2.5-3 volts., same for the #2 injector. The voltage on the #4 injector was 15 voltas approximately. Thats as far as i have gotten. I do have an ohm meter and know how to use it. Just not familar with the wire harness good enought to know where a short might be or which pin to measure at the ecm to check for a short in the wire. Another forum told me they thought it might be the ecm (computer) and that it might have a bad driver. However, when i went to order one today. The guy told me to make sure i didnt have a short or it could just blow the new ecm. Any help would be greatly appreciated.

I can do anything mechanically related if someone can give me some direction. I dont mind buying a rebuilt computer, but dont wish to do this if it is not the problem.

Well Chryslers do have problems with their PCMs & drivers in particular so that definately wouldn't be out of the questions.. The voltage you are getting to the injector is too low but comes up when you disconnect the #4 injector. The injectors get their power from the ASD relay and you should be seeing system voltage, 12 v or 14.x while running. I would back probe #2 or 6 and see what the voltage is when you disconnect #4. Also put a noid light on that connector & see if you have a pulse.

I would also be looking at the wiring harnesses, I've seen some problems with no evidence on the outside of the harness. I would start with the obvious stuff, maybe open up the harness under the battery to make sure there is no corrosion in it, look around for evidence of a damaged, pinched, moved, fluid saturated harnesses, grab the harness & wiggle them, see if that makes any codes come back or run differently, the injector harness in particular. You can disconnect the PCM connectors, find the power & ground circuits & verify those (maybe one of the guys with a good data base can hook ya up with a wiring diagram) , probe the other pins with + probe & key on, any 12 v reads on the other pins would indicate a short to power, with the sensors disconnected & a test light with the clip hooked on to the pos bat term, prob the connector pins & if its lights up that would indicate a short to ground........

If this was a straight #4 misfire with no injector pulse & good power it would be a slam dunk PCM(I'm assuming you've ohm'd the injectors to eliminate a shorted injector plus swapped them & the problem didn't move). All those codes you got 1st could still be a PCM, they will throw the kitchen sink when the go, but these are all reference voltage & power supply codes so personally if it was my call I thing I would want to make there isn'tanything going on in one of the harness, probably not, but ya never know............

I was assuming you have a 3.3L v/6


(This post was edited by Sidom on Jul 30, 2009, 5:35 PM)

HI,
My 2003 Town and Country has about same issue as yours. Climbed Grandfather Mtn in NC and car started running rough with 0204 and 0304 codes set. Changed wires and plugs and swapped out number 4 injector with no success.
Can you tell me what finally fixed yours? Appreciate any help

I have figured out what is wrong, but have not fixed it yet, because of lack of money. The initial problem is directly related to the wiring harness. Directly below the location where the fuel injection harness connects to the main engine wiring harness, my wiring harness was touching the engine block and melted all of the insulation off of the wires. But during this process it fried on of the circuits on my computer. Therefore, I have to replace the computer. I should have the money to replace it this Thursday. I will let you know.

You can see if this is your problem by following the wiring harness from the injectors (under the air intake) behind and under the power steering fluid reservoir, downward towards the back of he engine. There is a connector just below the power steering fluid reservoir. That is where mine was shorted due to the insulation being melted off the wires. I will eventually have to replace that portion of my wiring harness, but to test my computer, i have just replace the insulation on the wiring harness and protected this area. Its not hard to make the fix, but I couldn't tell I had a problem until I took the wiring harness off of the car.

Hope this helps

JD,
Well done my friend! Not only was the fuel injector harness melted but it was exactly where you said it would be just under and aft of power steering reservoir near the 10 pin connector. Also it was not obvious until I removed the outer insullation covering. Looks like this to be a common problem on 2003 town and country. Should be a recall- not sure if it is. New harness is about $ 225 at Chrysler but beleive I can repair old one with connectors and a crimper tool.

I temporarily insulated all the wires with tape and then started car - runs very smooth now. Computor is OK but unfortunately the shorted wires caused injectors to flood the engine when I was in the mountains and damaged the catalytic converter. Bought one on ebay for $213.
Thanks again. Believe ebay has computers listed also.
Cheers!
HB

Glad to hear you guys found your problems........Thx 4 coming back & posting your results.....

I have a 2002 Town and Country with a 3.8 posting the same code. I did find that the wiring harness was fried right where you said it was, just behind the main connector behind the power steering reservoir. I managed to fix it, checked all circuits. All circuits were good. However, when I reconnected the harness, and fired it up, the computer immediately posted the P0204 code again. I think it is the PCM, but where else could I check for a short or possibly damaged wires? Should I check from beyond the main connector, and trace back to the PCM first before I just fork out and buy a new PCM? I just want to make sure I don't have another problem with a frayed, pinched and shorted wire. I'm afraid of frying the new PCM. Thanks.

Let me first state that this was the solution for my problem, but I cannot see or guarantee that this is your problem. But if you have melted the wires like my car did, then you will likely have to replace the ECM. I bought a refurbished/reprogrammed computer from Ebay for $199.00 and it solved my problem and only took a week to get it. I think the name was Automotive Exchange. Just make sure that all wires are fully insulated. I recommend changing the fuel injection portion of the wiring harness, but i still have not replaced mineand it runs great! Knock on wood!!!!!

Thanks for the reply. I'm going to do one quick inspection of the rest of the wiring and get the PCM. I saw the paticular ebay auction for $199 that you were talking about too. I also re-routed the wiring to go up and around the power steering reservoir as well, so none of the wires touch the block. I think it will be fine for right now. I will let you know how mine went after I install the new PCM. Thanks for all your help.

I made the exact same change. I would continue to use the heat protection wrap that was on the wiring harness, just in case it touches again. You will need to have the VIN and mileage on the car when you call in to order the vehicle. If you buy over Ebay, you can send the seller a note. I like this method because PayPal somewhat protects you. Good luck and let me know if it works for you. Hope this post helps everyone, because I spent 2 months trying to diagnose and solve this problem. While another post did say the wiring harness could be damaged, without telling me to take the harness off to examine, I would never have found this problem.