A4 1.9 TDI (110hp) Avant EGR delete & Power Loss questions.

[Mudchute]

Hello everyone,

I've just got myself a 1996 Avant in banana yellow and its ace, so much car for so little money (140k mileage, fsh for £250!) however it has a an issue with power loss.

Its gutless! What power there is, is consistant but with no turbo torque steps or urges, just very flat with no step up in power at any point. I think the turno isn't kicking in and I can't even hear it wind up at all. I can see common themes appearing accross the internet involving split vacuum hose joiners, maf sensors and n75 valves. Any ideas? Is replacing the vac pipes first a good place to start?

Also, I want to take the inlet off clean the thick gunk thats no doubt in there and fit an EGR delete kit however I'm at a loss as to which kit to order. I see many have egr port blanking plates and also 50 ish mm dia' ally tubes with a ribbed end for mounting a hose and a flange on the other end. EGR Delete Kit For VAG 1.9TDI 90/100/110/115BHP - FR&R Tuning| MAHA Dyno Rolling Road Tuning| Stage 1, 2 & 3 Engine Performance Upgrades - (Powered by CubeCart) (http://fr-rtuning-shop.co.uk/index.php?_a=product&product_id=1904) I can't see anywhere that would go for my engine so I want to avoid spending £60 on a kit only to find out it has couple of blanking plates in it to suit my engine.

http://i14.photobucket.com/albums/a311/ihatesissycars/20120909_194556.jpg

As far as I can tell, if I removed the EGR valve I'd only have x2 holes to blank of with small plates? Audi EGR BLANKING PLATE A1 A2 A3 A4 A5 A6 Q5 Q7 1.2 1.4 1.9 2.0 2.5 TDI | eBay (http://www.ebay.co.uk/itm/Audi-EGR-BLANKING-PLATE-A1-A2-A3-A4-A5-A6-Q5-Q7-1-2-1-4-1-9-2-0-2-5-TDI-/130685976725?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item1e6d7dc095)

Does that make sense?

All help is appreciated!

[OddBallBoy]

Does it seem to drive ok until you try to use a bit more power, then you suddenly seem to have even less power than when you started it? If so, it's dropping into limp mode and is most likely due to a fault code generated by the MAP; low inlet manifold air pressure. And yes, split/perished vacuum pipes will cause that. As could a split in any of the intake pipes anywhere from the air filter to the intercooler to the inlet manifold. And sticky vanes on the turbo. N75, etc, etc...

Definitely worth changing all the vacuum pipes before you do anything else - just get a good couple of meters of silicon pipe off ebay for very little money. It's a very quick and easy job to do, the silicon pipes go on and off all the connectors easier than the rubber pipes, they'll last forever and if it doesn't work, at least you'll have ruled them out as being the problem. Would also recommend getting yourself a cheap code reader (VAGcom would be better but that would cost you the same as the car!) and then at least you can confirm the fault code is the MAP rather then the MAF, which if faulty would also drop it into limp mode. A cheap code reader will also let you check for any other engine, SRS and ABS codes as well. I have read posts before slating the cheap code readers but mine is VW specific, cost less than £30, has never caused any problems and has more than paid for itself in diagnosing issues I have had.

I had this limp mode problem on my Passat 110 TDi (AFN engine which yours may well be too?) and I did the vaccum pipes, checked all inlet system pipes, including the metal pipe that runs across the front of the car (pre-intercooler) as this can rust through, replaced the MAP (this was the fault code being thrown back but a fault code on the MAP doesn't necessarily mean it's the MAP itself that is faulty), tried disconnecting the MAF temporarily which made no difference, checked the turbo actuator rod was moving, took the turbo off and cleaned it using a specific turbo cleaning product, but none of these actions resolved the issue.

You can check the turbo variable vane actuator on the turbo is working - if you can connect a piece of pipe to this and use something to create a strong vacuum (sucking it is unlikely to be enough - if you could suck hard enough, you could no doubt make a fortune in other ways...), you should be able to see the actuator rod moving. I've heard that because it sits on top of the turbo, water can potentially sit in the well around the vacuum pipe connector and rust the actuator rod, even though you'd expect it to evaporate off due to turbo heat...

I decided to live with it, didn't want to spend a fortune on a new turbo (have heard mixed reviews of reconditioned turbos) and if I was gentle with my right foot, I could normally avoid it dropping into limp mode, and if it did, I just flicked the ignition off then on again quickly to reset it, even whilst driving. Bizarrely though, after nearly a year of driving it this way, whatever the problem was sorted itself out and it's been fine for the last couple of years! Runs perfectly even with 201k on it. Fingers crossed, touch wood etc, etc...

Unfortunately, it could be one of many things causing the problem but the best you can do if you don't want to pay a professional to sort it for you (I didn't, I'm too much of a tight a*** and quite like trying to sort things myself, find it satisfying) is work your way through everything as methodically as possible, starting with what you can check for little/no cost, ruling things out as you go along.

Good luck!

[Dan J]

Mines a one owner from new (though you wouldn't of thought it by the state of it when I got it) 160k
As per oddballboys post really, kind of described my situation since I bought my 97 avant tdi (110 AFN) to a T :)

When I bought mine nearly 3yrs ago now it was in a state on most accounts really, to start with vacuum pipes were very tired and worn, so they were replaced first as some were leaking along with one of the boost pipes going to the intercooler then I removed the inlet manifold and it was a wonder the engine actually ran because it was very clogged up with yrs worth of oil passing through it and solidifying , cleaned that out and got it back on.

Then blanked the EGR valve off by removing it and making my own plates up, got it back on. Alls good still

In the last 12 months amongst other bits I've had to clean the exhaust turbo vain as it was sticking and causing it to go into limp mode when just going past 3000 revs if I was pushing it a bit, read about this problem on here and sorted it :)
now runs sweet as a nut (purres like a cat) pulls like a train.

Have replaced quiete a few other engine related parts and suspention,brakes,which I won't bore you with as the list goes on, recently

had the oil cooler recently spit it's dummy out but that's another story.

Definatly clean your manifold out it will make a world of difference on power,tick over and ultimately fuel,
change your vacuum pipes as per oddballboys post, can be had for pretty much less than a fiver off ebay.
check boost pipes for leaks,and give the inter cooler an inspection for condition etc.
turbo vain could be sticking or restricted and not opening fully so check that, and actuator movement.

Mine runs much better now than when I first bought it, feels almost like a new car.

Happy fiddling :D

[Mudchute]

Hi guys, thanks for the adivce,

I'm gradually working through the list and I'm having some success. I've replaced some of the vac pipes with some hose I had although I've run out so I've ordered some more (4mm and 6mm id black silicone form ebay) although so far this has made little improvement.

I did notice that (crude and probably a bit daft but I thought I'd try it) when sucking on one of the pipes early in the system that there didn't appear to be a limit to how much air I could draw through it so this would suggest a leak however my knowledge of the cars vac' system is limited. I'll report back on this once I've repaired/replaced what I can.

I checked the operation of the variable vane system in the turbo and I couldn't get the actuator rod to move by hand. I wasn't sure if this was due seizure or the spring being too strong to move by hand but I elected to have a go at this.

I did the Mr Muscle clean/bodge and gave the ouside workings a liberal dose of wd40. I left it for 15 or so mins and tried working the lever again. It was still stiff at first but then something gave. I thought I broke it but persisted in working it and, success! It quickly regained full movement. I could comfortably move it by hand and it would spring back itself when let go. I worked it by hand (!) for a few minutes with lots more wd40 and it soon felt like a healthy system. A quick blast (with a big smoke boom at one point!) has shown a big improvement in bottom end torque in the lower gears and below 3k. The engine still bogs though when accelerating past 3k in higher gears going into the limp mode until switched off and on again but I believe the vac system to be at fault here. I'll replace the hoses, test its abaility to hold a vacuum and try again. I think the next culprit would be the N75 valve but I'll wait and see how the hoses go.

I'll report back any more findings for the benefit of others.

Hopefully all will be sorted soon then I can get on with the outside makeover. The inside of the car is mint but the bodywork and paint, a bit messy so I'l lbe getting the NATO green matte paint out along with a roller :D this combined with some -40mm psrings and big wheels should create quite the tank!!

[Dan J]

Hi guys, thanks for the adivce,

I'm gradually working through the list and I'm having some success. I've replaced some of the vac pipes with some hose I had although I've run out so I've ordered some more (4mm and 6mm id black silicone form ebay) although so far this has made little improvement.

I did notice that (crude and probably a bit daft but I thought I'd try it) when sucking on one of the pipes early in the system that there didn't appear to be a limit to how much air I could draw through it so this would suggest a leak however my knowledge of the cars vac' system is limited. I'll report back on this once I've repaired/replaced what I can.

I checked the operation of the variable vane system in the turbo and I couldn't get the actuator rod to move by hand. I wasn't sure if this was due seizure or the spring being too strong to move by hand but I elected to have a go at this.

I did the Mr Muscle clean/bodge and gave the ouside workings a liberal dose of wd40. I left it for 15 or so mins and tried working the lever again. It was still stiff at first but then something gave. I thought I broke it but persisted in working it and, success! It quickly regained full movement. I could comfortably move it by hand and it would spring back itself when let go. I worked it by hand (!) for a few minutes with lots more wd40 and it soon felt like a healthy system. A quick blast (with a big smoke boom at one point!) has shown a big improvement in bottom end torque in the lower gears and below 3k. The engine still bogs though when accelerating past 3k in higher gears going into the limp mode until switched off and on again but I believe the vac system to be at fault here. I'll replace the hoses, test its abaility to hold a vacuum and try again. I think the next culprit would be the N75 valve but I'll wait and see how the hoses go.

I'll report back any more findings for the benefit of others.

Hopefully all will be sorted soon then I can get on with the outside makeover. The inside of the car is mint but the bodywork and paint, a bit messy so I'l lbe getting the NATO green matte paint out along with a roller :D this combined with some -40mm psrings and big wheels should create quite the tank!!

Yes the rod will be stiff and give you some resistence, sounds like your was well and truelly seized, you may have to do the mr muscle trick again and move the rod up and down whilst it's in there so you clean the crap off the inner bit that moves, I did this on mine, the first time I did it it was great but the problem crept back in after about 4 months so I didn't do it for long enough, boosts up a treat now throughout all gears.

The only way to ensure you haven't got a leaky vacuum system is replace all possible pipes you can. Costs less than a fiver ;) Edit: youve ordered some.

Again I'd strongly suggest removing the inlet manifold, you will be shocked how clogged it is, this will be effecting the performance for sure past 3k revs and upper gears, in 5th gear mine pulls like a train from 60 to upper limits:biglaugh:

Any tips you need regarding getting the exterior sorted just shout.

[Mudchute]

Thanks Dan, hopefully the hoses will yield results.

Rethe outside what I need is for someone to come along and offer me some really cheap springs and some really cheap wheels!! I need to replace a wing too and the n/s one is a bit beaten up, are they hard to remove?

[Dan J]

Thanks Dan, hopefully the hoses will yield results.

Rethe outside what I need is for someone to come along and offer me some really cheap springs and some really cheap wheels!! I need to replace a wing too and the n/s one is a bit beaten up, are they hard to remove?

Yes mate you'll notice straight away if they've made a difference. Get on that inlet manifold aswell ;) It's only 4 bolts :D
while was messing about with all that I also cleaned and decreased the inter cooler which had a fair amount of crap in it,
never done a front wing on these but when I had the front end off of mine (cambelt change) it looks pretty straight forward to remove the wings, a few top bolts running along the top where the bonnet shuts either side and a few down the inside where the front door hinges are, there might be others hidden behind the inner arch skins but not sure so just a guess on that one im afraid.

[adamss24]

I would get pd130 intake and hoses then get a Allard EGR delete if you want an improvement to the way the engine breathes ! The 1.9 Tdi AFN is not particularly fast in stock trim but can be made fast with bolt on mods. Getting a set of 0.216 nozzles (as fitted to the old shape audi a6 140 Bhp or transporter T4 150Bhp) will give you a min of 20Bhp. Get an old skool tuner who can solder in new sockets on the ECU and have new maps fitted and you will have 150-160 Bhp ! If that's not enough then GT1749VA turbocharger (as fitted to the pd 130 audi a4/a6 and vw passat) fits without modification and it's good to 185Bhp with supporting mods. If you want even more then BV43 turbo and 11mm pump + PD 130 lift pump will be good for 220 Bhp max. then you need head work to keep it all together ! Stage 1 and 2 will be ok on the stock clutch, any more and you will need a stronger clutch: AWX dual mass flywheel and Sachs SRE clutch should hold nicely whilst still feeling stock.
The beauty with the old VE engines is they get better with power and the economy does not suffer at all !
I had a AHH 90 Bhp engined audi a4 which could pee all over vr6 golfs, the AHH is a 90 Bhp engine with a VNT turbocharger and 11mm pump ! I ported the head, fitted forged rods, twin valve springs and titanium retainers from Rosten performance then used a thicker head gasket, PD150 head bolts and Bosio Race 520 nozzles (0.260 size). I fitted a PD130 turbo and i could get the clutch slip in ANY gear. I then fitted a BV43 and had less clutch slip and a lot more top end. Unfortunately i crashed the car and i had to pull the engine- the flywheel was just about to break as it was cutting the retaining bolts due to the torque. The car was still running the stock 90 Bhp map !
Here's a clip if you want to watch soon after rebuild- note that i don't rev the engine much over 3.5k - the clip it's low quality as i was using the mobile and in one instance it was raining as well but you can see the difference ! Click on the links...
http://i840.photobucket.com/albums/zz323/adamss24/th_littleclip.jpg (http://s840.photobucket.com/albums/zz323/adamss24/?action=view&current=littleclip.mp4)
http://i840.photobucket.com/albums/zz323/adamss24/th_060711-1841.jpg (http://s840.photobucket.com/albums/zz323/adamss24/?action=view&current=060711-1841.mp4)

[Dan J]

Hi Adam, interesting post :) what are the gains of the Allard egr kit over just putting blanking plates on the standard valve?
Do you mean pd130 inlet manifold or just the boost pipes air box and front intake into the air box?

Im not looking for big power as I don't think mine would last if I did but changing a few simple bits to get it breathing better I'm all up for.

[Mudchute]

Update time, I'm replaced all the vac hoses (some were in a bad way) and also found a split in the inlet manifold/pipework join. I've also removed the EGR and fitted some blanking plates and now, what a difference. It pulls surprisingly strongly, much better than I thought it would! I'm very impressed!

I can set about some decent maintenance now. Its not long had a service but another won't hurt. I'll tackle the belts too and set about cleaning as much of the inlet system out as possible.

I've got some used ebay coilovers at home and some 18" rs4 rep's too.

I appreciate this car has its faults but each one has been straightforward and fixable without too much fuss. I've had to replace the front anti roll bar link rods plus a track rod end and again, due to the way its made it all happened so easily. Looking at the rust and mud covered track rod end filled me with dread thinking seized tapered joints threaded bar/lock nuts but no, 10 minutes and it was done. Its so well made. I' think I've been converted to ze way of ze germans!

Anyways, thank you all for your help. Once I've got everything up to a good level of condition and functioning I'll be back wanting some more info on tuning! My girlfriends 2.0 dti Alfa Giulietta trucks along like freight train so it'd be nice to outrun her for a change!

[Mudchute]

Update, The car performs very well now, grunty and with little smoke too. I'm still getting a dip in power though when accelerating through 3rd mostly. As the revs pass 3k the engine holds back for about 500rpm then power comes back. It doesn't go into a permanent limp home mode just briefly during full throttle situations. Any ideas?

In all other situations it appears to perform as I'd expect however I have no benchmark to measure it against.

I know the variable turno gubbins is vac operated. Is its resting position in the low down spooling up position or the top end spooling up position if that makes sense? Reason I ask is that I still think I have a lack of vacuum. Is there a vac pump somewhere I can trace the system back to? I see the black plastic bulb like part acting as a reservoir but I can't see now't else.

I'm asking as my heater control is laggy and would I be right in thinking that this is also vacuum operated like some cars? A lack of vacuum woud explain why I'm getting both problems... Or I'm talking c**p!

[Doctle Odd]

Those AFN engines are pretty bullet proof. I blocked my EGR at the valve end of the cooling pipe with 2mm steel using the pipe as a template. In Ireland the yearly test NCT is pretty thorough and I thought they might notice the missing pipe. It's slightly easier to run less smoky and slightly more pokey. A good remap would bring it up to 135-140 brake without harming it. Give the turbo vanes the mr muscle treatment and plenty of wd 40 on the actuator. You don't need to delete the EGR off the ecu.

[Mudchute]

I've removed my EGR valve altogether as most mot testers here coudn't care less so long as what comes out the back is fine.

I like the idea of a remap but don't like the idea of the cost. It'll cost more than I paid for the car! Is there a cheaper alternative...

[Doctle Odd]

A good remap 2-300 I suppose. You can get chips you just plug into the pump, badly made ones will screw up the car. Some people swear by them they do add horsepower and increase economy. Bad one 25 ish adjustable one from a company that doesn't want to look like gits is 80 ish. I have driven a Passat with a bad remap it drove like a 1968 Vauxhall Viva, I have driven a Bora with a €100. chip it was a rocket