Engine damage

G60DAN

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Right happy days got my S3 back last weekend after having forge con rods fitted and new

water pump
oil pump
piston
piston ring set x4
chain tensioner
cambelt kit with belt idler
con rods
big end bearings
forge 007 DV

all at the cost of £2190.92
and still have a code coming up of 17963 chargr pressure maximum limit exceeded
off 2 see bill on sunday hope he can sort it as its doing my head in
 
That's exactly the same fault as mine, quite a lot of these popping up recently. First thing to check is the N75, i gave mine a clean and it seems to be behaving.

Quick test with a multimeter to check if it's 'ok' . Should be between 25-35ohms, mine is at 31ohms. I think the closer it is to 35ohms the faster it reacts (aggressive) the closer it is to 25ohms the slower it is (smoother)
 
i had the same problem on my s3, i turned my actuator down alittle as it was going over the standard psi limit on the ecu
try turning down a clearing code see if it comes back
 
That's exactly the same fault as mine, quite a lot of these popping up recently. First thing to check is the N75, i gave mine a clean and it seems to be behaving.

Quick test with a multimeter to check if it's 'ok' . Should be between 25-35ohms, mine is at 31ohms. I think the closer it is to 35ohms the faster it reacts (aggressive) the closer it is to 25ohms the slower it is (smoother)

where did you get this info from?
internally their bores differ which is why some control differently to others... spikey so called "race" valves etc
 
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Extracted from generation dubbs:

here's some info I compiled from various posts regarding the different valves..
I had a dead n75 in my car when I had purchased it... causing me to do alot of research

So these are what I've found so far.
058-906-283-C 20-30 ohm
058-906-283-F 25-35 ohm
034-906-283-H 25-45 ohm
034-906-283-J 20-40 ohm
034-906-283-K 20-40 ohm

word is C has been superceded by the F. I don't know anything else about the H,J, or K.

"...as we now know, the N75 regulates boost pressure based on the ECU's signal. The only problem is that the N75 is pre-designed to react a certain way to this duty cycle signal. Since there are various turbos out there and various [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]engines[/FONT][/FONT][/COLOR][/COLOR] to pair them with, there are several different revisions of the N75 that you can buy from any VW/Audi parts dealer.

The main change between these various N75 valves is the way that they react to the duty cycle signal. Some valves have a small threshold for the need to lower or level out boost pressure. Some valves are intended to allow much higher boost levels and hold them even throughout the entire RPM range. In the end, the ECU still controls the valve's open/closed state. The valve just reacts faster or slower to these signals.

The main part number for the N75 valve is: 034906283.

Each revision of the N75 has a different letter added to the end of it's part number.

Here is a current list of the various N75 valves that you can find at your local VW/Audi dealership and what motors they were made for:

034906283C - Oldest valve, A4 1.8T original
034906283F - Newer revision for 1.8T (maybe 170HP or TT 225)
034906283H - 1991/1992 ABY [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]engine[/FONT][/FONT][/COLOR][/COLOR] and AAN [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]Engines[/FONT][/FONT][/COLOR][/COLOR] in S4/S6
034906283J - 3B [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]engine[/FONT][/FONT][/COLOR][/COLOR] in early S2
034906283K - ADU and ABY [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]engines[/FONT][/FONT][/COLOR][/COLOR] in late S2 and RS2

There are alot of places on the web that offer "upgraded" N75 valves for your 1.8T/2.7T.

ECS-Tuning sells a "race" valve. THis valve is infact the N75 version "H". It will cause boost to spike very high and in some situations cause your ECU to cut power in fear of detonation (also called "limp mode").

The N75 version "J" is a very popular model. It makes the K03 react very linear throughout the RPM range and doesn't cause the "limp mode" problem with most 1.0bar chip programs.

The N75 version "K" is an uncommon version to see in use but, it is very similar to the "J" version and many people see no need to bother with it.

**NOTE**: As with any upgraded item for [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]your [/FONT][COLOR=#0066CD ! important][FONT=inherit ! important]car[/FONT][/COLOR][/FONT][/COLOR][/COLOR], check to see if other people have tried this part with the exact same program you are using on your ECU to see what the effects are.

On a side note, most ECUs will have a preset limit for boost pressure. The ECU can determine the boost pressure by reading the air mass as it enters the [COLOR=#0066CD ! important][FONT=inherit ! important][COLOR=#0066CD ! important][FONT=inherit ! important]air [/FONT][COLOR=#0066CD ! important][FONT=inherit ! important]filter[/FONT][/COLOR][/FONT][/COLOR][/COLOR] end of the intake pipe. By pairing an upgraded N75 with a high boost ECU program (ie. GIAC "X" chip) you are very likely to hit "limp mode"
 
Well I will let Bill sort it out this Sunday thanks for all the input.
 
I got it from various different sites Bill, is it wrong? I'm not a 100% that i'm correct on the whole 'ohm' thing :ermm:

N75 Ohm test range 25-35? - Passat World Forums

part number question? N75 valve - AudiWorld Forums

http://www.audi-sport.net/vb/a3-s3-...tar-performance-testing-day-%96-pt4-n75s.html

Apologies if i got this all wrong

thanks for the links.. the resistance ranges quoted are large.. 20ohm-40ohm doubling??
i believe their internal apatures are different which is why the control is different

but I could be wrong.. lol
every days a school day
 
thanks for the links.. the resistance ranges quoted are large.. 20ohm-40ohm doubling??
i believe their internal apatures are different which is why the control is different

but I could be wrong.. lol
every days a school day

Next time you have a dyno day we'll check the N75's to see if different readings give different delivery :)
 
Thank god. I just mine through the post from the UK and it was an E. I thought I'd have to send it back! ASN sorts me out yet again.
 
Interesting they're on the E version - wonder if the parts any different from the F....