Problem after upgrading to RS2 Specification

[GazzaG60]

id put the original coilpacks back on. see if the misfire goes away. id expect it ti be clean through 1st and 2nd.

[orsum]

Changing back to the original coil pack may cause another issue the dwell on ECU has changed to 2ms because of the R8 coil packs, not sure what effect that would have on the standard coil pack which have I think was about 4ms.

Basically they would only fire for about half the time.

[newsh]

Yes original coil packs may well misfire on the shorter dwell.
Have you done a boost leak test yet?

[orsum]

No I have not done the boost leak test. I do not have the kit to do it, will have to buy a test kit and try later.

Over the coming weekend I will be checking the MAF voltage feedback and I am thinking of ordering a Lambda sensor. I read the Lambda is good for 60,000 miles if that's true I have done 65,000 which could mean it needs replacing. Further checking needed.

After my drive yesterday the problem in my mind appears not to be a spark issue, it does not feel like an electrical issue its not a sort of on or off action more like a surge of coming and going power which is leading me away from a spark issue.

Boost leak
MAF
Lambda
Fluctuating fuel pressure

[Rusty]

MAF plug is always worth a look.

Misfire could be poor ground on the wiring harness.

[Jonas_R]

You should check the following:
- boost leaks
- Mad connector
- Fuel pressure
- AFR values while flooring it, maybe you are running to rich or lean
- I don't think lambda is your problem since I'm pretty sure ecu does not use it at wot

[orsum]

Yep agreed.

Please add figures if anybody has any.

You should check the following:

- boost leaks.

- Mad connector. Will check the voltages, have pulled some figures off the net. All be from a VR6. Do you have any figures for the S2 or are they all about the same?dings

1995 VR6 Brand New MAF Readings
Idle: 0.86-0.89v
2000rpm: 1.27v
3000rpm: 1.55v
4000rpm: 1.85v
In all cases, the voltage was pretty stable and constant. It would fluctuate by 0.03v at idle, but pretty slowly.
It seems to have fixed the problem. I drove the car and the revs seemed to drop significantly faster when returning to idle, and there was no power-loss or misfires during my test drive.
One big catch: After testing the new MAF, I put the old one back in to verify the old readings. Today, it wasn't reading high, but would occasionally fluctuate between as low as 0.5v and just over 0.9v when idling.

- Fuel pressure. 4 bar

- AFR values while flooring it, maybe you are running to rich or lean Not sure what the values are meant to be, do you have any figures?

- I don't think lambda is your problem since I'm pretty sure ecu does not use it at wot. At the price they are will buy one to try.

[Jonas_R]

Maf connector - change the pins on the maf plug.

Afr - should be around 11.5-12 at wot and full boost.

Regarding lambda then prj or Paul can confirm it or maybe others but i'm 90% prj said that it does not use it at wot.

[kinaputt]

What fuel pressure is the map made for? Do you use a RS2 fuel pressure regulator?

[orsum]

Prj if I recall correctly said it was mapped for 4 bar.

The car has the the standard ABY system which I think is the same as the RS2

[eJaYr]

I think fpr are different on rs2 and s2

[Jonas_R]

S2 = 4 bar
rs2 = 3.8 bar

[orsum]

Waiting for Prj to advise exactly how he set the system up.

When logging into the ECU it tells me the software is something like MAP 3 VER 3 from Dmitri.

[theyagaraj]

Hi or sum , I have had similar issues a few times... The most common problem most of the times was the rubber adapter hose near the throttle body at back of inlet manifold which tears and is impossible to see unless you take the rubber adapter off and check for tears....
it generally will give you black smoke ...
the other problems I have experienced once are
wrong spark plugs...
maf
fuel pressure regulator
two modules on bulkhead
theyagaraj

[orsum]

Thank Theyagaraj.

What plugs are you using.

I will be checking everything. Thanks for your input.

As you know its been a project of mine to get as close to perfect as possible and I did expect a few issues its just getting the time to do the investigation.

This weekend it the golf clubs Ann competition and I will most likely spend quite a bit of time having some fun.