CEL on, glow plug light flashing, limp mode, Help!

I'm on the road, the problem started about 1,000 miles ago. The car would go into limp mode and the glow plug light would come on. I could shut off the ignition then restart and the problem went away. I took it to the dealer in Fatteville, NC, no codes came up. The problem has since increased in frequency, and now the CEL is on, the glow plug light is flashing, the car is in limp mode and restarting doesn't change anything. A beep also sounds upon startup. I'm in Daytona, Florida, it's raining hard out, and I don't trust driving in a Florida monsoon in limp mode for several miles to a dealer I don't know... any ideas are appreciated!

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'99 NB, manual, 100k miles, new injector pump by VW, new TB

Have you had your brake switch replaced? if it is failing (ON) then your car will go into high idle mode (because it thinks the brakes and the throttle are being applied at the same time.

moondawg

Had the bls replaced by the dealer in April, still under recall warranty. No issues since then, many miles later... until this.

is the synthetic turn signal fluid routed through the CAT filter, do you use the waste oil to recharge the potato chip? lol

Well I took it to the dealer, it took them 2 hours (190 bucks so far) to tell me that I need the intake and throttle body cleaned, would that cause these symptoms?

Well I took it to the dealer, it took them 2 hours (190 bucks so far) to tell me that I need the intake and throttle body cleaned, would that cause these symptoms?

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No. But it's not surprising that they would recommend a solution that doesn't correct the problem you actually have.

My guess, and that's all it is, would be a loose connector from a sensor, somewhere. I think a CEL will almost always generate an error code; I don't understand how you can get a CEL but not an error code.

The ECM will always try to optimize performance based on the inputs it gets from the various sensors. Limp mode usually indicates that one of those inputs is out of spec.

Actually, it sounds like either fuel starvation or air starvation. The cel is probably one of those 'max fuel exceeded' kinda things. The other is a lack of boost pressure from a sticky turbo or bad N75.

Well I took it to the dealer, it took them 2 hours (190 bucks so far) to tell me that I need the intake and throttle body cleaned, would that cause these symptoms?

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No. But it's not surprising that they would recommend a solution that doesn't correct the problem you actually have.

My guess, and that's all it is, would be a loose connector from a sensor, somewhere. I think a CEL will almost always generate an error code; I don't understand how you can get a CEL but not an error code.

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Well the second dealer did find a fault code: 18047, "sporadic throttle sensor switch." Two dealers, 3 hours, 270 bucks, guess I need to get a new laptop that will run the VAG, for those prices I could have bought the software.

Weedeater, you are the second person to mention the N75. I ordered it from Impex, I'll put it on and see. I would rather spend 100 bucks on an easy fix that makes sense, instead of paying the dealer big bucks for something that doesn't, and might not fix the problem. Let alone busting my ass on the intake myself and still not correcting it.

There was another person with a similar problem, apparently the throttle sensor switch can go bad and cause the car to go into limp mode, you may need to replace the one on your car. If I recall it is held on by 3 10mm bolts and is near the accelerator pedal. You may need to search for "limp" or "switch".

Here is the link, they called it the "floor pedal switch" which sounds like your Throttle Sensor Switch.... If that is the same switch, you might want to check your part number, then this is your problem. http://forums.tdiclub.com/showflat.php?C...rue#Post1131956

I replaced the N75--actually it is called the wastegate regulator valve in my manual--now the car won't start. This not starting has also been an issue recently, sometimes I need to crank it for 10 or more times before it catches. Turns over fine, just no igniton. Have 5,000 miles on a new injector pump by the dealer, what could this be?

Re: CEL on, glow plug light flashing, limp mode, H

Do the following:
1 Replace break switch. If no cure, reinstall the removed one and sell the other on e-bay.
2. Replace throttle position sensor switch (the one on the diesel padal). If cure, ok. If not, check if the pump that was replaced recently is bad. This can happen. Hopefully, this should solve the problem, including lot of cranks.

Re: CEL on, glow plug light flashing, limp mode, H

OK, having searched the forums for starting problems, I came up with the 109 relay, so I got one from the dealer and that seems to have fixed the starting problem. Drove it ~10 miles today on the new N75, so far seems fine, will log some more miles and report back. Am also wondering about the throttle sensor... can't find it in the manual... where do I find it, what is it called, how much does it cost? It sounds like a good thing to have on hand.

Re: CEL on, glow plug light flashing, limp mode, H

Check the link on my previous post, they were calling the Throttle Switch the Floor Pedal Switch, probably because it is right next to that pedal on the floor, you know the one that makes you go faster, yes that one on the right.... Oh wouldn't that also control your Throttle..... Maybe only in Germany though where they tend to be more precise in their description of functions, go figure...

Re: CEL on, glow plug light flashing, limp mode, H

Thanks! Had a brain cramp, you had listed everything, all the clues were there... it's called a pedal switch with sensor actuator or something like that, dealer wants an even gross for that, I'll check IMPEX for their price. It looks to be the actual accelerator pedal, the rod, and the box that the rod pivots in, which has an electrical plug connector and is secured to the inner firewall by three nuts. Whew.

Re: CEL on, glow plug light flashing, limp mode, H

dang double post

Re: CEL on, glow plug light flashing, limp mode, H

Update after 100+ miles, with no problems:
N75 fixed the CEL/limp mode/flashing glow plug light
109 Relay fixed the no-start problem

Total cost $130 plus a donation to Fred's (how do I do this? the link isn't working for me) ...a lot cheaper than letting the dealer clean the intake which wouldn't have fixed the problem!

Thanks to everyone who responded, also to drivebiwire.

Here is something I learned from the Bentley manual on this go-round:
"The accelerator pedal is directly connected to the ECM via a potentiometer. This eliminates the need for an accelerator cable and is known as 'drive by wire.'"

Anyway the car has once again gone from "worst nightmare" to "the best car I ever owned."

Re: CEL on, glow plug light flashing, limp mode, H

Congratulations, good to hear that you have sorted out your problem....

I have a very similar problem. I went to pass a guy today and just as I finished passing him my car went to limp mode with the flashy glow light. After cleaning out my shorts due to the loss of power while in the oncoming traffic lane at 120KM/hr, I was able to turn the car off and restart it fine but the flashing light was still there and continues to be there after 200km and a few starts. I've done some reading of the posts and here is what I know of my car based on what I've read.

1. Brake lights are ok and turn off and on with the pedal fine.
2. I have a spare 109 relay but havn't changed it yet. Does it have to fail completly before it generates a fault?
3. Cruise control works
4. Glow light flashs about 1 min after start, even if you don't touch the throttle.

I think the glow light fault resests itself every start so would it be the TPS if I don't even move the throttle and the light comes on?

If it was relay 109 wouldn't it take some bumps or jarring of the car to flicker the contacts?

What is N75? Would that generate the flashing glow light right after startup?

Any suggestions on what to replace first?

Thanks

Any suggestions on where to start?

Start with determining what the fault code(s) is(are).