URS6 Need Help!!

[iain1067]

i think i may have some chips from my old S6 that give around 280bhp that you could try,.

iain

[twoqu]

Which MTM conversion is it? The 264PS one?
As I recall that conversion should use the 3 bar map sensor on the S4/6 but not the
S2!
Are all the boost readings from the dash display or a good gauge?

[Andyh-R6S]

I had the boost pressure checked previously when I first noticed the issue after the ECU mod’s and it was all OK and the same person said there was no error codes to suggest a fault! (How can I get at theses error codes without Audi or a tuner getting involved? If I can get at the codes, where would I find out what they mean? Many thanks)
It has been suggested that it might be a week fuel pump and/or cannot supply the fuel quick enough, etc? (Some times plays catch up, if you know what I mean.) I must admit the car is 10 years old now and running more boost than stock, so all the kit that looked past it or was defective in some way, I have been working my way through. (1 bit out, 1 bit in) To systematically work the issue out of the car. I must admit, the fuel thing might have something in it. As if you slowly go through the rev range and boost, the issue is not really apparent. (Even in the rev/pressure band and flooring the throttle the issues sometimes does not occur) So, if with more boost you need more fuel pressure to keep the fuel mixture to the correct proportions, am I getting fuel starvation to the injector rail, putting a higher output pressure pump in and the associated bits might be worth while, especially if I do more stuff like a ‘RS2’ turbo and injectors. I just wanted to cure the issue before the next modifications.
So, has anybody done any mod’s to their cars ECU and had to change the fuel pump and associated bits to sort out a similar issue?
************************************************** **********************************
And just to answer a few questions:
It did it after the remap but was not totally obvious like now.
The original coil packs had cracks to the cables all over the show and I found two plugs wet on the outside. Replaced all the kit and new Bosch plugs, torqued them down correctly (2nd time a 100 miles later (Cleaned the oil out of the plug holes first) and in this department all appear to be OK))
Waistgate had been worked on after the ECU mod, new diaphragm, spring, etc. (I do think it needs setting up though. As it was adjusted to get try and get rid of the issue.
Boost jitters around when the issue occurs but eventually goes to ‘2.1, 2.2, sometimes and 2.3’. Boost slightly slower to rise after the tuner adjusted the Waistgate setting. It had been pointed out by the tuner, that I should have an instrument cluster gauge boost of around ‘2.4 to 2.5 bar’ but in the intake system the boost was correct. (Possible low set cluster gauge)
How can I get at the ECU codes with out expensive bits of kit and what do they mean?

Many thanks to you all.

Now bed time for a few hours.

[Andyh-R6S]

The car was not particularly behaving it when I first got it a few years ago and it potentially might have done the issue before but was not obvious. But it did have odd chips and wires disconnected that were all put back correctly during the mod to:
270bhp Modified MTM motronic computer with 3 bar map sensor.

[merlin's S4]

IMO your thinking a bit too much about this! I've personally not heard of a fuel pump causing problems at these boost levels. Almost everyone on this forum is running chips or a remap of some discription with no problems! Although you should change your fuel filter as a matter of course if it's not already been replaced. You need to work through the suggestions that have already been made or take it back to your tuner. I would still do a pressure check first. Doesn't sound like you've done one since fitting the new hoses and it could just be a loose clamp or something.

[merlin's S4]

It's easy to get the fault codes from an S4/S6. If you take the dash (dials) out you'll find an empty bulb holder on a cable somewhere in behind. If you put a bulb in it you can use it to blink the codes. It's a good idea to place it in one of the empty bulb slots in the dash so that it's available whenever you want. To check it's working turn on the ignition, it should light up with your other warning lamps (ABS etc) and then go out. Now open the relay box under the bonnet and you'll see the two diagnostic ports, one black and one white. To blink the codes you need a short bit of cable, with the ignition on place one end in the white block and one in the black and hold it there for 5-10 secs. The diagnostic lamp you just fitted should light up and then proceed to flash any stored codes up. For code list see here http://www.sjmautotechnik.com/troubl...g/20vcodes.htm

Alternatively buy one of these http://www.carbulbs-direct.com/u280-...anner-34-p.asp

You'll need the extra OBD2 cable listed.

[Animal Mother]

It's easy to get the fault codes from an S4/S6. If you take the dash (dials) out you'll find an empty bulb holder on a cable somewhere in behind. If you put a bulb in it you can use it to blink the codes. It's a good idea to place it in one of the empty bulb slots in the dash so that it's available whenever you want. To check it's working turn on the ignition, it should light up with your other warning lamps (ABS etc) and then go out. Now open the relay box under the bonnet and you'll see the two diagnostic ports, one black and one white. To blink the codes you need a short bit of cable, with the ignition on place one end in the white block and one in the black and hold it there for 5-10 secs. The diagnostic lamp you just fitted should light up and then proceed to flash any stored codes up. For code list see here http://www.sjmautotechnik.com/troubl...g/20vcodes.htm

Alternatively buy one of these http://www.carbulbs-direct.com/u280-...anner-34-p.asp

You'll need the extra OBD2 cable listed.

Or buy a nice cheap VAGcom cable.

[newsh]

I was thinking that, TPS reading WOT on and off so you go from spring boost to ecu boost and back again.


Other than that, and this is a pet thing for me at the moment as it caused so many problems with my car, is that there may be a small boost leak in the feed to the ECU or even inside the ECU or to the boost gauge if you have one. I sincerely recommend you do a proper boost leak check, many of us on here have sets of plugs to block off the pipes and apply pressure, I dont know how many times I've heard "It was checked and it all looks good" only for a boost leak to show up later, has the intercooler O ring been replaced for example? Were the threads on the hose clamps greased when the hoses were replaced? If not it is unlikely they are tight enough, you'd be surprised where the air leaks out when you put a Bar or so of pressure into the system.. Often the smaller hose clips can be done right up tight but are still not putting enough pressure on the pipe (the problem with my ecu hose) Trimming back the hose and remaking the joint is only a temporary fix as the hose compresses again.

I Forgot, did you replace the DV? A leaky one can cause surging too.

[Animal Mother]

I was thinking that, TPS reading WOT on and off so you go from spring boost to ecu boost and back again.

I Forgot, did you replace the DV? A leaky one can cause surging too.

Was thinking of both of these too. A new DV should be compulsorary with any power upgrades, preferably a piston type. TPS sometimes only needs a clean up.

Seems to me like you have a number of possibilities. Do the right thing first and pull the codes. Buy a cheap set of leads from China.

[S2central.net]

OK here's my take on it...

1 - Perform a thorough boost leak test

2 - Pull fault codes - but remember that many faults are NOT detected by the ECU

3 - Try another MAF

4 - Try another throttle pot (TPS)

5 - If none of those single out the problem then you might wish to get the ECU properly examined to establish if the correct chips (for AAN with Automatic) are there and they match the MAP sensor fitted. A mismatch there could give problems. I have never modified an ECU for an Automatic S4/S6 before but I could give it a whirl if you wish - seeing the MTM ones will certainly help

Paul

[Animal Mother]

OK here's my take on it...

1 - Perform a thorough boost leak test

2 - Pull fault codes - but remember that many faults are NOT detected by the ECU

3 - Try another MAF

4 - Try another throttle pot (TPS)

5 - If none of those single out the problem then you might wish to get the ECU properly examined to establish if the correct chips (for AAN with Automatic) are there and they match the MAP sensor fitted. A mismatch there could give problems. I have never modified an ECU for an Automatic S4/S6 before but I could give it a whirl if you wish - seeing the MTM ones will certainly help

Paul

HOMEFRY! HOMEFRY! HOMEFRY! HOMEFRY! HOMEFRY!

Bin the MTM, get a homefry. Homefries are great.
Maybe they should now be called Ulsterfries!

[S2central.net]

LOL at that one - you should be in Marketing

[twoqu]

Still a bit unclear about how you are measuring boost pressure!
If its from the stock boost gauge in the dash, then it will be inaccurate with a 3 bar map sensor. Also boost pressure will be anything geater than 1.0 bar indicated. A good check assuming you are more or less at sea level is to see what it reads with ign on. Should be 1.0 or 0.9 bar.

[iain1067]

For a dv change go for the S3 one, the urs4/6 doesn't have the O ring seal on the intercooler, if you are seeing a peak of 2.3 bar and regularly see 2.2 on the digi gauge i would say you have a pretty tight system already, my old s4 and s6 when modded would see that all day long. If you have a 3.0 bar map sensor then i think you need to correct the figure shown on the boost gauge, the only way of telling is to open the ecu.

The S6 does also have down by the ecu (passenger footwell under the carpet) a water / condensation trap this is part of the pipe that gives the ecu boost pressure, i have seen bad connectiobs down there also.


Iain

[Andyh-R6S]

Hi all,
Many thanks for all the advice.

Just to make it obvious, the car did the issue before both the ignition was changed for the ‘034 Msp’ kit and the Samco hoses were fitted. So nothing has changed in that department, although I did find lots of cracked vacuum hoses that were starting to go, so I replaced them all. The only place I have not been vacuum wise, is the ECU area and the water trap. That will be done over the next two weeks when I get time. The interesting part is, only when hot and only when flooring the throttle between ‘1.2 to 1.7 bar’ and around ‘3250 rpm’ (ish). An it is repeatable when it does it. I do see anywhere between ‘2.1 to 2.2 bar normally and sometimes ‘2.3 bar’ under exceptional circumstances. I know it’s not the ignition kit as it is the same issue before that set of kit was changed and although I think the vacuum circuit is robust because of what I see in boost terms, I will have it checked again. I do know that when kit gets hot and vibration is interlaced into the equation that all sorts of phenomena can happen. ((Especially ECU EPROM contact!! I will publish an article I wrote for something else that considers this issue and if you have EPROM’s are changed in the ECU the potential for an issue exists but I will cover that somewhere else) Pushing them and putting a tie wrap round them is not good enough. Round hole and a rectangular pin section, heat and vibration, say no more)
Oh, I did change the dump valve for an AMD bit of kit a long time ago but that made no difference either.

I will make a list of all the potential areas to look at and tick them off one by one. (I put the list down here for you all to comment on, just in case I miss something.)

I will now search ebay for a diagnostic lead and a Stag/Intel EPROM reader. (I can read the code (My past job will come in handy here!!))