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General Information => Troubleshooting => Topic started by: Smokey Eddy on March 06, 2013, 10:29:24 am

Title: tdi egr and ecu issue
Post by: Smokey Eddy on March 06, 2013, 10:29:24 am
2000/1999.5 ALH golf
cleaned a terrific amount of sludge from the egr, intake and runners after the car went into limp.
Car is dramatically faster now but still in limp mode...
I also snapped the MAF diaphram arm ... so i wired it open is that ok? My aaz didn't need one :P

tons of hard carbon bits must regularily go through the engine because of the egr... such a good idea.... in theory.
Title: Re: tdi egr and ecu issue
Post by: 745 turbogreasel on March 06, 2013, 11:44:30 am
I think the reason EGR buildup is so bad is that none of the carbon leaves the intake.

I'll bet $2 its a MAF problem.
Title: Re: tdi egr and ecu issue
Post by: shorttimer on March 06, 2013, 05:10:39 pm
I'm eliminating the EGR on my AAZ build. Just found a 1.6TD exhaust manifold. Direct swap with no EGR.
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 06, 2013, 08:46:56 pm
Yeah that's how I had my last car. So anyways, I disconnected the battery for an hour and tried again... still goes into limp. Why or how does that valve in the intake help the engine?
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 06, 2013, 08:51:50 pm
Sorry, do I mean maf?  Its the valve that's part of the egress valve but not the exhaust valve the big one on the diaphragm.
Title: Re: tdi egr and ecu issue
Post by: 745 turbogreasel on March 06, 2013, 09:06:40 pm
(MAF) normally pertains to the Mass Airflow Sensor, and the computer will always *** a brick if it  isn't working.
On an ALH, you might be talking anti-shudder (ASV) or Exhaust Gas Recirculation(EGR), or conceivably the VNT actuator.

If you don't have means of checking the OBD codes, you should at least look onto an ELM scan device.

OK, my alphabits are all wore out now.
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 06, 2013, 11:00:16 pm
the vnt actuator? yes this is the thing i broke i believe. it looks like a throttle body...
(http://i49.photobucket.com/albums/f279/edmcclung/temp_2_zps43513550.jpg)
i broke the arm that comes out of the black diaphragm in the left of this image
Title: Re: tdi egr and ecu issue
Post by: 745 turbogreasel on March 06, 2013, 11:21:11 pm
Anti Shudder valve, I'm not sure the  ECU can detect that...
Check you didn't poop loose a vac line behind the intake, maybe on one of the N75  valves back there.
Bit of carbon keeping the EGR from closing? -plunger opposite the spaceship in your palm
Ruptured  EGR diphram? - put a hose the the bit in your palm in the pic, and suck or blow, if it leaks, it's toast.

Looks like it was due for a cleaning.
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 07, 2013, 10:36:54 am
I noticed the car shudders a tad when I turn it off. Doesn't bother me and for $350 its gonna have to. I think I could have mixed up the vac lines. Can someone snap a pic for me? Or post one if they have one?
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 07, 2013, 10:45:58 am
And of the two sensors that are back there. One is longer than the other so I think I got it right but I don't know what is now throwing the CEL. Hmmm at least the diaphram will be easy to test. If the valve is stuck or broken do you guys recommend I replace it or remove it?
The intake was way more plugged than that. No wonder I thought the car was so slow. I did the burn method - works superb. Just keep a rag and a bucket of water with you.
I checked the valves at the back all are connected.
I'll have to remove it again and see if its stuck or what.
After I start the car I can get to almost 3,000 rpm before it limps and its way faster now until the CEL trips. It just cuts boost and makes the car smoke black like crazy.
Title: Re: tdi egr and ecu issue
Post by: 745 turbogreasel on March 07, 2013, 01:27:55 pm
It will do exactly that if the N75 for boost control isn't hooked up, or is plumbed  the wrong way.  Checl both ends of the little hoses, they get pretty crispy after the first decade or so.

Can you get Q-bond at your local auto store?  It works great for fixing plastic craps like that arm.

Bad EGR valve will give constant check lamp unless you can turn off EGR request in VAG-COM
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 07, 2013, 06:53:07 pm
Okay. I have a couple meters of replacement line. Checked what I could find and looks to be all connected but I don't know that its correct. Can anyone verify the position of them?
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 07, 2013, 06:54:58 pm
I burnt the carbon off the valve but I wrapped the diaphragm in an ice cold soaking wet towel. Ill try and get my lips on there and see if its still bust.
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 08, 2013, 03:45:56 pm
Update, the diapram doesn't leak if I blow or suck on the hose. One of the charge pipes was loose. Fixed that and that cured the smoke and most of the power loss bit the CEL is still coming on after about 30 seconds of running.
Title: Re: tdi egr and ecu issue
Post by: theman53 on March 08, 2013, 07:56:38 pm
If you could use a test light on the Glow Plugs. I know it is weird to say, but mine went like that. Fine before I started messing with it and after had the cel? Or take it to a place to run the code.
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 08, 2013, 09:38:50 pm
I know two of them are burnt out but they didn't trip the cel before. Ill certainly replace them pronto in case they are the cause of the trouble. Thanks for the feed back guys. I have a feeling the egress its self is stuck open. Ill take it off again on a day I don't have to work. How much vacuum is needed for the valve to operate?
Title: Re: tdi egr and ecu issue
Post by: Smokey Eddy on March 13, 2013, 01:01:06 pm
The light stopped coming on ... car drives fine... didn't do a thing.
Just wanted to say thanks for the help fellas.