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2004 Jetta 1.8t Auto

My car cranks without starting and Ive tried everything else. Since VCDS is giving fault code 01314 - Engine Control Module (49-00 - No Communications) I figure that the ECU is probably fried and the next thing to do is swap it out. Ive been trying to learn as I go but could use some pointers. From what I understand I need to find a used ECU with the same exact part numbers as mine. I believe I have Immobilizer III being a 2004. Do I need to bring the car to the dealer to be able to pull the PIN for the immobilizer and adapt to the new ECU? Is there any way I can do this myself? I know I can adapt with VCDS, but I dont have the PIN. If I do have to take it to the dealer, since my car wont start, do I need to have it towed or can I just bring the old fried ECU and the new replacement? Any advice is greatly appreciated.
 

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INteresting, that code normally speaks to the inability of the VCDS program to speak to the ECU. traditionally caused by an faulty install of an aftermarket stereo. ECU may be "fried", but i would be hesitant to throw that kind of cash at it on a hunch.
 

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INteresting, that code normally speaks to the inability of the VCDS program to speak to the ECU. traditionally caused by an faulty install of an aftermarket stereo. ECU may be "fried", but i would be hesitant to throw that kind of cash at it on a hunch.
I am definitely hesitant to do that. I had thought from what I found on other forums that that code was indicative of a ECU gone bad. Im just trying to figure out what else I can try, I am really stuck at this point. I have a thread for my problem and what all I have tried (including the VCDS scan), if you wouldnt make taking a look and seeing if anything sticks out to you:
http://www.vwforum.com/forums/f15/2004-mk4-jetta-1-8t-cranks-but-wont-start-75458/
 

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It seems you are to a point where it may be best to trailer it into a shop and have them diagnois it. just have a good place that can work on it do the diagnois and then trailer it home and install what they said you needed (if you have the ability to tow it yourself and skills to do the work indicated)

To me, it sounds like it has spark, and air, but there is a terrbile vac leak or plugs are toast and spark is irratic/blowing out the spark before it turns over.

I am wondering if it is really the accellerator having issues and the ECU codes are casued by that. Accelerator Position Sensor code you show is that of a failing gas peddle in a drive by wire car and "could" case the Check DTC Memory - Intermittent codes for the ECU.
Rosstech says to Check Measuring Value Blocks (MVB) in VCDS, did you do that as well i presume?
 

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It seems you are to a point where it may be best to trailer it into a shop and have them diagnois it. just have a good place that can work on it do the diagnois and then trailer it home and install what they said you needed (if you have the ability to tow it yourself and skills to do the work indicated)

To me, it sounds like it has spark, and air, but there is a terrbile vac leak or plugs are toast and spark is irratic/blowing out the spark before it turns over.

I am wondering if it is really the accellerator having issues and the ECU codes are casued by that. Accelerator Position Sensor code you show is that of a failing gas peddle in a drive by wire car and "could" case the Check DTC Memory - Intermittent codes for the ECU.
Rosstech says to Check Measuring Value Blocks (MVB) in VCDS, did you do that as well i presume?
Thanks for your thoughts. This was my first time using VCDS, so I dont have experience with Checking Measuring Value Blocks, but Im checking out the RossTech manual and will do it tonight. Ive always had BMWs, so this is my first real experience with a VW. This has kind of become a personal challenge and I would really like to figure it out without resorting to bringing it to the shop (though I may eventually do that anyway). Another thing...the injectors arent getting pulsed when I try to start the car, so I assume that the ECU is not sending the signal and/or signal not getting to injectors. I can get a start every time with starting fluid, and then it immediately dies. Could I still have a vac leak or spark issues rather than fuel delivery problem?
 

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If you're getting it to turn over with starting fluid then I would be looking at the fuel system. You said you're getting no injector pulse so I would start there on why aren't the injectors getting power. It may not hurt to check the wiring going to your head unit. Even though it has an oem head unit unless you're the original owner I would be wanting to know if the car had one at one point and the wiring back there is chopped up. I think it's worth the 5 mins it takes to pull it out and just make sure it hasn't been messed with at some point as far as it giving you the code about the ecu
 

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You can always dry crank to check spark. Unplug fuel pump fuse and crank it with the plugs out of the block to view.
 
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