Help with Vacuum system please / 17964 Vagcom error

[alictait]

Hi guys,

After developing an intermittent power loss fault on my B5 00X 1.9 TDi, I purchased a Vagcom lead. I am now getting the following error on my shareware version.

17964 - Charge Pressure Control: Negative Deviation
P1556 - 35-10 - - - Intermittent

Checked out the wiki here which is recommending that I initially check the pipes between components. Other than what I can basically see from the top of the engine are there any main pipes that would cause the issues. I have already noticed a couple of potential discrepancies with the pipes and trimmed some of the ends off already. (no change though) I have also ordered some new pipe to replace any larger sections that I find.

The second recommendation is to

• Check Solenoid Valve for Boost Pressure Control (N75)
• Check / Clean / Replace Charge Pressure Control
  • Check / Clean mechanism for variable nozzles

This means little to me so if anyone knows of a how to guide then can they please let me know, or alternatively would purchasing a haynes manual assist?

Any help appreciated, and apologies if it has been posted before, I did search but anything I found didn't really give the advice on how to do it.

Cheers

Ali

 

[dieselfitter251]

I'm not sure it's the same problem but it may just be that your ECU spits out different Jargon to mine.

The bit that sticks out is 'Charge Pressure COntrol' . I think this relates to the Charged air system, or intercooler and pipes to us...
Check out this thread...
http://audi-sport.net/vb/showthread.php?t=66673

There are two of these units, they're both identical but operate on different ends of the intercooler system, one for inlet, one for exhaust. The one that went on mine was at the back of the engine mounted on the rear of the I/C pipe (just in front of the bulk head, vac pipe runs to the ECU and one to the intake air box and one to teh turbo) but the other is between the front right (drivers side) of the engine and the radiator area, a bit tricky to see and even trickier to get to. Once you start inspecting these you'll also notice the spaghetti of vaccum pipes.
I've started replacing the smaller vac pipes (role of vacuum hose = £15ish) and am going to start on the larger pipes in time.

As for the points 1 and 3 in the recommended fix I'm not sure, there are some tit-bits of info in the haynes manual and check out www.vagcat.com , it's quite helpfull too.

Oh yeah, and my engine is an AFN , yours may be different but I'm guessing it can't be that much different. My local Audi garage was actually quite helpfull, who'd a thunk? eh?!

 

[alictait]

Thanks for the info, just trying to digest it now - lol.

My engine is the AJM 85kw one, Don't know if it will make a difference, but like you I am about to just start replacing the pipes that I can find / get to.

I think I have found where the N75 Valve is so will at least change all the pipes leading to and from there.

Where did you get your pipe from, I ended up getting silicone stuff (seen others replace with this) from ebay as no local suppliers had itm guy in local parts shop said that there was no call for it and Audi wanted over £8 a metre and they never had it in stock anyhow. Question is whether I will need hoseclips with the silicone stuff. I have found a length that looks like it will go to the valve near the radiator, that feels as though someone has sliced the front part of it off.

Good informative post that you gave me the link too, sounds as though you have been through what I am about to try and rectify. Its so hard just now not to get tore into it though before my hose actually arrives. lol, Great to actually get a picture of the valve in question.

Thanks for the help, will report back soon.

 

[dieselfitter251]

Aye, loadsa head scratchin on my part too! I got the smaller braded hose from Audi for about £15 I think.. 35mm diameter? that was for a 5meter roll. I think your local guy was just lookin for a sale, assuming were talking about the same stuff. The larger 50mm was about £18 for a 5meter roll.

www.vagcat.com

you'll need to register, but a really valuable site!

http://www.vagcat.com/epc/cat/au/A4Q/1997/157/49/1767715/

items 10 -22 i think

 

[alictait]

Cheers for the links m8, still don't understand them though - lol,

Anyway, don't want to speak to soon but I think I have been lucky and sorted it just by changing the hose. Hose didn't arrive till 3.30pm today as my post is so so late around here, but well done to the guy for posting it yesterday and me receiving it today, even if I bought from Audi at the £7.61 + Vat per metre I wouldn't have got it till tomorrow.

I have changed any of the hoses that have looked dubious and there was one that was particularly bad that led from what I think is the exhaust recirculation unit that went straight to the N75 valve that is tight behind the radiator. I spent an age getting the bolts undone that were holding on the N75 valve as they had seized, the one on the bottom was a ****** as I didn't have any ramps to try and get it from underneath, so eventually Jacked it up with my trolley jack which is precarious enough as my driveway is red chip stones. After getting the bolts off I then couldn't get the electrical plug off of it and didn't want to force it just yet. So with the hoses replaced that I could get easy access too I started to reassemble. I had taken out the Air filter housing to give me easier access to everything. I decided that the likelihood of just replacing the hoses fixing my issue would be slim so only put the n75 valve back on with the top bolt and very very loose. So with everything back in place I came in, had my tea and then ran back out to take the car for a quick run and wow !!!, Seems like a new car so far, as I said I don't want to tempt fate as I couldn't open her up too much because when I did The loose N75 valve started flapping about in the engine (never thought about that), so will have to wait until tomorrow till I get that fitted properly. Initially though there was def. more pick up, and it didn't go into limp mode at all.

Fingers crossed

 

[dieselfitter251]

Well done then... If even one of the hoses is perished enough it could collapse under the required vaccum, sounds like you've sorted it. Just be sure to reset your fault codes, my car's done over 275k so I think (now that I'm about aquire a garage) I'll be replacing as many as I can.

£7.61+VAT a mtr, must be a different pipe to the sections that I bought.
Where abouts are you in South Lanarkshire?

 

[alictait]

I stay in the Clyde Valley, what about yourself is it East Lothian ?

I don't know why the dealership was so dear, he didn't know off hand what the hose was so had to look into the Vacuum system diagrams to get the part codes, maybe he was just giving me the top whack price.

Are you a mechanic yourself then ?

My car is (only) at the 155 K mark, Ive had her for 4 years and put 50 K on the clock, done most of the work on it myself along with my brother, although Its going to be due another timing belt soon (about 45 K since the last) and I may well be putting it in to a garage to get it done. My brother done it the last time, but he is still having nightmares about it - lol. I must admit though that I love the car, not remotely interested in changing it - especially now if I have rectified the issue. (thats quite a cool smilie too)

Do you know if you can program key remotes without the full version if Vagcom ?, I have tried the one key in the ignition whilst the other locks the door malarky with no joy.

Anyway thanks again for yout help, I'll report back later once I have had a chance to get everything nipped up and get her tested.

 

[alictait]

Well,

Out at 9 this morning to get everything tightened up and reconnected. I couldn't for the life of me get the bottom bolt in on the N75 Valve so its been left out till I can get it on a ramp and get access underneath. Seems secure enough just now though.

Thought it was still gubbed though as once I had it all connected I took it for a run and it was worse than ever, took it back home and whilst I had been putting it all back together another hose had slipped off, so a reconnection later and presto ---- sorted.

Only problem now was that whilst checking over the rest of the engine I thought I saw a wire off on what I have since found out to be the fuel temperature sensor, So I decided to investigate and managed to pull both wires right off of it. Never even left enough wire on it to get a new connection to it.

Put it on to the Vagcom prior to fixing and guess what - Fuel temp sensor flagged as an error code (wasn't there before, so was obviously fine initially). Had to remove the electrical connection (which I broke in the process) and sliced back the plastic to bare enough wire to get a new wire soldered to it. A bit of dodgy soldering later and managed to get it fixed, Not as neat as it was but its sorted and no more vagcom error.

Cheers again for your help.

Ali

 

[dieselfitter251]

Not a mechanic but I've had enough grazed knuckles to gain a bit of experience and have a go at most bits and pieces. Timing belts give me the fear though, anything that requires 'special tools' or heavy enginge work, I've striped a couple of top ends with my dad but I'm not confident enough myself. In saying that though, 237K on the Stinky it should be getting de-coked and reground and all the rest! Scared to touch though incase it falls to bits!. afaik you will need a full copy of vagcom to code keys but don't even ask how. There may be some links in the tech/vagcom forum... also check out the US site www.audiworld.com those boys are pretty much on the game, I spent quite a bit of time on there before finding Audisport.

I'm currently at the end of the M74 and moving up to East Lothian next week, if you were still having problems I was going to swing by (two folks scratchin their heads is better than one!!!) but it sounds like your on top of it. If you can be bothered, have the time and don't mind working outside it may be easier the take the bumber off to get into the front end. Check out the link in the FAQ's section of the B5 forum about getting the car into 'service mode'. It makes a lot of stuff easier to get to in the front end. About your temp sensor wires. A lot of the sections of the loom can be bought seperately, or even make your own. As long you take your time and insulate any spliced wiring from water you should be fine. Good luck, hope to see you in the B5 forum!

 

[alictait]

Cheers for the offer, that's very kind of you, had I not got this far I would have def taken you up on that. So glad that it seems to be rectified though as its been going into limp mode for about 3 mths,had been getting progressively worse probably as the main pipe deteriorated.

Ive had the car in service mode before when my brother was doing the timing belt, I think its going to be a lot of sweet talking to him to get there again. How long have you had your ca ? Have you put it into a garage to get the timing belt done ?

Ive had a look at the Audi world forums before I hate the layout of them. Ive also found the Audidiy.com forum very good, once I discovered how to navigate that too.

I have managed to fix the fuel temp sensor issue for just now. Next time I am passing a scrappy though I think I will jump in and grab a few bits n pieces including the switch that I broke in the process, Its insulated up just now but I had real trounle trying to get into the wires to reconnect. The wiring that went to the sensor is part of a bigger loom and there was very little play available in it. I don't have the nimblest of hands, but I got there. Just was annoyed with myself as I tried to fix something that didn't need fixing.

The Vagcom has been invaluable though, I don't understand the more technical stuff it can do otherwise I may have been tempted into buying the full package. Had it been still $2 to the £1 I prob would have, byt £75 is prob too much just now just for me to reprogram a couple of keys.

Thanks again for all your help and generous offer.

Ali

 

[dieselfitter251]

Agree'd on the keys. My ignition barrel broke a while back and as my car is a grey import (brought over by a squaddie in '97) they had to replace the whole barrel and give me two new ignition keys. Check out the price from a dealers, if you've already got the keys it may be relatively cheap?

I usualy put mine in to get the tb done! Yes I'm a chicken.

I've had mine for about 2 1/2 yrs and put 66k on it...!! ABS is currently shot, need two rear ABS sensors and as it's a quattro they're dealer only parts.... £130 quid a pop. Tried parts from a scrappy but they just don't cut it...

Good luck with the B5, I may be getting rid of mine soon. I need something newer with less mileage and I can't afford a B6, so I may go for a BMW or VW.

 

[alictait]

Agree'd on the keys. My ignition barrel broke a while back and as my car is a grey import (brought over by a squaddie in '97) they had to replace the whole barrel and give me two new ignition keys. Check out the price from a dealers, if you've already got the keys it may be relatively cheap?

I usualy put mine in to get the tb done! Yes I'm a chicken.

I've had mine for about 2 1/2 yrs and put 66k on it...!! ABS is currently shot, need two rear ABS sensors and as it's a quattro they're dealer only parts.... £130 quid a pop. Tried parts from a scrappy but they just don't cut it...

Good luck with the B5, I may be getting rid of mine soon. I need something newer with less mileage and I can't afford a B6, so I may go for a BMW or VW.

Ouch on the ABS sensors, I guess it won't be happening then. Ive had mine for 4 years, got a good un at the time. About a week after I got it the Airbag light came on on the dash and has been on until I got my Vag com last week, which reset it and it hasn't came back. Shortly after I got it I had to change the MAF but other than that its been pretty cool.

Can you remember how much the timing belt cost you in a garage. Was it up here that you got it done ?

Do you really need something newer, thats the question Ive been asking myself and really with my car running well I could trade it in put £10K to it and not have anything better. Whereas now its costing me very little and I love it.

For some reason I never got the thread reply notification, but then I haven't gotten a few recently, very strange.

Ali