VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: johnboy on May 14, 2007, 03:56:40 pm
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Hi guys, great forum!
Ive spent a couple of hours browsing the forum and I was wondering if someone could give me a basic outline of the mods I can make to the AAZ engine.
I have a 96 Passat Estate TD with a later AAZ engine (with EGR) which I want to increase the performance of, while keeping reliability.
Id like to boost the power to around the level of the 90BHP Tdi without changing too many parts. Is this possible?
Although Ive tuned a few petrol engines and despite working in a VW parts dept, Ive never really worked on diesels before so all info would be appreciated!
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first off.. delete the EGR.
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OK, what benefit will I see from ditching the EGR? Is it as simple as blanking off the EGR connections to the manifolds and any vacumn pipes?
Also found this link while browsing...
http://vwdiesel.net/phpBB/viewtopic.php?t=579&start=0&postdays=0&postorder=asc&highlight=&sid=6aaee06478055559febc40fcf1a4d895
...which seems to be the kind of thing Im looking for, however the pump on mine looks a little different...
(http://i49.photobucket.com/albums/f275/retroscort/DSC00310.jpg)
(http://i49.photobucket.com/albums/f275/retroscort/DSC00311.jpg)
(http://i49.photobucket.com/albums/f275/retroscort/DSC00312.jpg)
(http://i49.photobucket.com/albums/f275/retroscort/DSC00313.jpg)
Are the principles the same?
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the principles are pretty much the same.
as for EGR, it basically dumps soot and sludge into your oil, as well as gums up your intake.
if you remove the intake manifold, you will see a lot of sludge buildup in it... cleaning it out might actually give you a couple of hp from better airflow!! :lol:
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johnboy, i too have a td aaz engine in my mk3 golf and i went to the derv doctor in derby who increased the boost from 0.8 bar to 1.2 bar and increased the fuelling whih made my motor bhp increase from 75bhp to 95 bhp. give gavin a cal mate.
http://www.thedervdoctor.co.uk/
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OK, guys, Ive had chance today to properly compare my pump to the pics in the make your 1.9td faster thread.
Can you take a look at my pics compared to the originals and make sure Im on the right track!
(http://i49.photobucket.com/albums/f275/retroscort/Smog105410470.jpg)
(http://i49.photobucket.com/albums/f275/retroscort/Smog105410471.jpg)
My pump doesnt have numbers 1 & 2, so i guess i can forget about them!
Number 3, the fuel cut off solenoid...
(http://i49.photobucket.com/albums/f275/retroscort/DSC00314.jpg)
Number 4 solenoid...
(http://i49.photobucket.com/albums/f275/retroscort/DSC00312-1.jpg)
Number 6 and 7 are clear on my pump but is this screw number 5?
(http://i49.photobucket.com/albums/f275/retroscort/DSC00310copy.jpg)
and Im guessing mine pump doesnt have number 8, but maybe you can see something i cant!
(http://i49.photobucket.com/albums/f275/retroscort/DSC00315.jpg)
(http://i49.photobucket.com/albums/f275/retroscort/DSC00313.jpg)
Also Ive been looking at what might be involved in removing the EGR system. Im guessing I can dump the whole lot and simply run a vac pipe between A&B
(http://i49.photobucket.com/albums/f275/retroscort/EGR.jpg)
Will I need to do something with the wiring to the change over valve (pos8 on the etka screen) or can I just leave it plugged in?
Again all advice will be appreciated!
thanks to nogama3 too for the info, although id like to have a go myself first!
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Sorry to somewhat hijack the thread, but what is the purpose of the shock absorber looking thing that goes between the throttle and pump body? Mine had one, but I took it off as it had absolutely no resistance.
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Good question! Mine also has no resistance so Im guessing its knackered! Im guessing its some kind of vibration damper??!
Also just noticed taht Ive put the arrow for number 3, the fuel cut off solenoid, in the wrong place, its actually below the immobiliser block I think!
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i thought that thing was to eliminate the sticky throttle...
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i thought that thing was to eliminate the sticky throttle...
...Could be!
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Thought Id let you know how Ive got on.
First off I decided not to touch the solenoids on the pump, mainly because of the fact that it is fitted with an immobiliser which i didint want to screw up!
I borrowed a very accurate digital boost pressure gauge from work (the proper VAG tool!) so take some readings
Started by taking a max boost reading before touching the pump =0.89 bar (12.9 psi)
Then turned the fuel screw by 1/2 a turn after breaking off the anti tamper tabs, and adjusted the idle back.
=0.94 bar (13.6 psi)
Finally ive after adjusting the wastegate and giving the fuel screw a further 1/4 turn ive ended up with 1.09 bar (15.8 psi)
The result is a definate improvement, although the car still isnt going to break speed records, it certainly feels more torquey and driveable!
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i think that shock thing is to stop the lever from snapping back and causing the abrupt engine braking. mine still worked but i removed it because it also hangs the revs between shifts
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I'd also love to know the answer to the question of what should be done with the valve number 8 (POS 8) in the diagram. I have this thing still in place but no wires attached. Am I sacrificing power?
thanks
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I'd also love to know the answer to the question of what should be done with the valve number 8 (POS 8) in the diagram. I have this thing still in place but no wires attached. Am I sacrificing power?
thanks
Cant seem to find a definative answer to this. Ive asked a couple of the mechanics at work (I work at a VW dealer) and they dont know! One guy who might know is back from holiday this week so Ill ask him!
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Johnboy, my car is set up at 1.2 bar with the fuelling adjusted to meet the demand!
i hope that helps. apparently, it is quite safe to take it upto this level as long as the fuelling is adjusted.
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number 3 and 4 what is it for and what should i do with it?number 8 is probably sterring the EGR i remove wires from it:)and it's OK
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No's 3 & 4 are simply the the pipe that takes the exhaust gas from the manifold to the EGR valve.
Im planning to make some blanking plates up for my manifolds soon to see if I notice any difference without EGR. I plan to simply disconnect the vacumm tube and see what happens when I disconnect the change over solenoid.
As for more boost, 1.2 bar (17psi ish) is safe is it!
Im tempted to have a play, but I need the car to stay reliable!
Any ideas on how hot the exhuast gas temps would be at that kind of boost?
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Had a chat with couple of guys at work about the vacumn change over valve.Basically its there to aid caold starting and to hlp prevent run on after the engine is stopped, its not essential, but if youve got it, you might as well keep it connected!
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Made up some blanking plates for the EGR and fitted them today. WOW I honestly can't believe the difference in performance! The engine will rev right up to the red line (4500rpm on my rev counter, didnt want to rev it any harder!) and was still pulling, when before it was running out of steam at 4000rpm!
Very easy mod, any well worth it!
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How fast is your car from 80-120kph in fourth gear? thats 50-75mph.
I have basically the same car, but an eco-version, would be interesting to see how big difference there is in performance after mild modifications.
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Id say with the mods ive done, that the car is definatly more responsive and tourqey.Its not loads faster but for a big car and simple mods, it is worth while
Ill get back to you...
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Did you forget to test 50-75mph?
Here's my times:
80-120kph in 4th gear = 8,35sec
80-120kph in 5th gear = 10,6sec
I'm still running stock eco-IP (tweaked), no IC, stock exhaust, Garrett T2 and stock airfilter box. Boost 1-1.2bars.
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No mate, didnt forget, Ive been away on holiday this week so didnt get a chance. Ill find out soon.
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Ok checked the times very roughly today using the stop watch on my wrist watch! and to be honest theres nothing in it.
4th gear 9 secs
5th gear 12 secs
When you say yours is a eco version what do you mean by that exactly?
In the UK all the 1.9TDs are basically the same, with very few diffrences in the 5 or 6 years they were available and all have the AAZ engine code.
I think VW called them "umwelt" in the UK, and they were always marketed as a high efficiency engine.
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The Eco IP doesn't have the boost enrichement system on the top of the pump. The engine doesn't get any more fuel under boost, just air.
The car has a cat and about 55kW stock, no intercooler.
I can't get any more out of my pump without running superhigh idle, maybe if I cut out a piece of the lever to get it further back!
This is probably as fast as an ECO-diesel gets, with all parts stock.
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I see now! All UK AAZ had boost enrichment as far as Im aware. Sounds like the performance of you car is good considering its limitations!
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Hi, been reading this thread, very interested. I'm about to add an intercooler to my 1.9TD vw transporter t4 and obviously need to do pump mods. (ABL engine code)
My pump look like the one in the pics, however mine does not have a fuel enrichment device attached. Does anyone know if and how these can be retrofitted and where I can source one (UK).
Sorry to highjack the thread but I thought you might be able to help.
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It's doable:
http://www.vwdiesel.net/phpBB/viewtopic.php?t=8693
I'm going to do this as soon as I get my mercedes on the road again, it seems to suck all my money at the moment :roll: