Inconsistent limp mode

I have a 2005 Jetta TDI with a BRM engine, and I keep getting codes p0101, and p0404, and the "emissions workshop" message. Last fall, I threw away a lot of money by letting one of the local stealerships touch it. To be fair, I used to live in Fargo, ND, and the VW stealership there is fantastic; competent mechanics, and reasonable prices. Here in Colorado Springs, Penkhus is pathetic (but that's another story for another time).


Anyway, when I brought the car there, it threw these codes, and still does. In theory, I have a new EGR valve, and a new upstream o2 sensor. The real problem causing limp mode the most was a hole in an intake tube, which I fixed.


Now, when the temperature is below 20C, and I'm on back roads, limp mode almost never happens. When the temperature is above 30C, or I'm surrounded by other cars, limp mode happens much more frequently. I experience a slight shudder, or a significant jerking (like there is insufficient fuel reaching the engine), sometimes it just happens while I'm coasting. Yep, still the same codes, and the same "emissions workshop" message. To resume normal operation, I stop the engine, and restart, then go on driving. I have noticed that sometimes I can smell coolant, and the coolant smell happens almost every time I'm using the AC.


A little background on this vehicle:
Last summer, I traded my 2006 old New Beetle TDI (which I'd driven for about 120k miles) to a small stealership because I wanted 4 doors. After a few weeks, the intake leak started, and it was all downhill from there. The timing belt was replaced about 191k, I'm not just over 222k. It might have a new EGR valve, and upstream o2 sensor from last fall. I replaced the air filter last fall, and I'll be doing that again today or tomorrow. There doesn't appear to be any obstruction in or around the intake. I can't see or feel any fluids leaking from anywhere in the engine bay. When I start the car cold, I think there is a small puff of gray smoke, but the coolant level seems consistent.


Thanks all.

I hope someone can point me at something that I haven't thought of yet.

Might want to look through the MKV forum instead of the MKIV. Not sure why they replaced the O2 sensor since it has nothing to do with either of those codes (you will usually get a P2196 on a TDI).

Keep in mind that car is probably due for a camshaft at that mileage.

You need to watch the Actual vs. Requested MAF data when the EGR is commanded on and off. See if it is doing what it should be doing. I'd also check the thermo-flap in the bottom of the air cleaner. It is almost certainly bad (they pretty much all are by now). That can mess with the MAF values, as it not only is getting a steady diet of super heated air, but when the EGR cooler starts leaking, it essentially turns the entire air cleaner into one big low pressure EGR valve, and often ruins the MAF, especially if you have a poor/wrong air filter installed.

Thanks guys. I will see if I can get time to poke around for something that matches your description this weekend.


I saw another couple of comments elsewhere about the camshaft. If so, this jetta is getting recycled.



As to "Why would they replace an o2 sensor with those DTCs?", that's part of a long story that ends in me contacting VW, only to be told they trust their stealerships (and by correlation, don't value their customers). That's why this is my fourth, and last VW.

acfreema said:

......................................that ends in me contacting VW, only to be told they trust their stealerships (and by correlation, don't value their customers). That's why this is my fourth, and last VW.

Click to expand...

Yes, but the repair business is a separate entity under the same roof. There are some good ones, very very few.
There are a lot of things listed in the Ross-Tech wiki for P0101 (couldn't find the other) including fueling, lots to diagnose. Many folks, even shops, will just replace whatever component is listed, a big mistake. The ECU is a very simple system, not comprehensive, it just reports what it sees. The camshaft bidness you're reading about is mostly from dealers not using the proper oil back in the day.

You have had bad service, it isn't really the car's fault. Or the brand, for that matter. I can parade a dozen cars just like yours in front of you that are very reliable cars and their owner's love them.

Oilhammer, it is the brand.

In a nutshell:
I contacted vw with a complaint about repairs, exchanged a lot of information regarding what I brought them (a broken car), and what I drove away after paying roughly $1200: a car with 100% of the problems that it had before I donated to Penkhus' retirement fund.

After much telephone, and email exchange, they said they trusted that their technician did the job correctly. What the technician didn't do is take the duct tape off the intake pipe to find a 1" hole. His notes didn't even mention duct tape.

There is much more to the story, including a blatantly lying service manager, but I did promise only a nutshell worth of story. That is why the replacement for this vehicle will be a BMW or subaru, and I will not touch another product made by vw. I was very pleased with both of my tdi beetles, and my wife's 2009 jetta tdi that we sold back because we were moving to a place with emissions testing. In the end, I can only vote with my few dollars, so I'm taking my money elsewhere, and never looking back.

So long, cya!

We understand why you feel the way you do about the brand. But it ain't the brand and it doesn't matter anyway. I follow the Honda CR-V forums and can't believe some of the stuff I read from clueless dealer repair departments, especially on their newer cars.
Follow any advice by OH, you'll get home.