View Full Version : Switching ECU's and BKR6E Gaps?

08-05-2012, 11:13 AM
Hey guys

I bought a used ECU and was just wondering if there was anything special I need to do before switching over the ECU's other than disconnecting the battery? Will anything get "locked" during the switch over? Or do I need to reprogram anything on the new ECU (it is the same as mine, manual tranny, etc)?

Also, I bought some new BKR6E's to put in and was just wondering what the best gap for these plugs is? Note: I have 2.0T coil packs (if that changes anything)

Thanks guys,

08-05-2012, 12:54 PM
IIRC you need to gap your plugs at .040 when using the 2.0T coils.

08-05-2012, 02:16 PM
Damn that much. Thanks.

Anyone else?

08-05-2012, 03:21 PM
For a 2001 there are a few different things to code on the ECU:

FWD or quattro
ESP or regular ABS
Manual or Tiptronic
Maybe something else I'm forgetting

It would be worth checking the coding on your existing ECU and making sure it matches the new one. As far as resetting things goes, just make sure you have the radio code if you're rocking the stock CD deck.

On the 2.0T coils people will often run up to .044" gap. You can actually buy the NGK plugs gapped that way already. They would be BKR6E-11 (1.1mm gap). Gapping the regular ones up that high is not recommended as the surfaces are no longer parallel. I'm running the "-11" plugs as is, right out the box. I just checked the gap first before install. Diagnosticator actually runs them up to .050" with good results.

08-05-2012, 03:27 PM
Great thanks.

So I guess 0.040" should be good for the BKR6Es then.


08-05-2012, 04:18 PM
Great thanks.

So I guess 0.040" should be good for the BKR6Es then.


Please read the replies, the one above says not to run the BKR6E's at .040 as you bend the electrode too much and they are no longer parallel. If you are going to run the larger gap please use the BKR6E-II as recommended in the post above your last one.

08-05-2012, 04:42 PM
Please read the replies, the one above says not to run the BKR6E's at .040 as you bend the electrode too much and they are no longer parallel. If you are going to run the larger gap please use the BKR6E-II as recommended in the post above your last one.

[confused] Well howardfootball said to gap them to 0.040", and walky said that people have gapped them up to 0.044" (although doing that you mine as well buy the BKR6E-11 like he said)...

He said that they would not be parallel anymore if you gapped them up high like 0.044"...I'm talking about 0.040"...

Either way I think I have to up them a bit because the way they come stock is too low for 2.0T coils.

08-05-2012, 05:32 PM
You got two replies, one says you need to put the gap at around .040 and another said people typically run up to .044 and some go as high as .050. Nowhere did howardfooball say to use the standard BKR6E and stretch it out to .040, he only said it should be around .040. Walky_talky20 said generally people run around .044 and they use the BKR6E-II plugs for this and they come gapped at around .043. The BKR6E plugs are gapped at around .032 and if you want to push them to .040 then that is a .008 difference whereas the BKR6E-II is only .003 larger. What I was saying basically comes down to listen to walky, the guy knows his shit and if he recommends it then I would listen. I'm not his buddy or trying to suck up but I have not read much from walky that wasn't dead on. Re-read his post and follow it and you will minimize problems down the road.

You can easily open the plugs you have now to .040 and they will probably be good but you do open the door to new problems. When you are under full boost and the plugs are going like mad the electrodes actually start to straighten out as things heat up increasing that gap even more which will cause a poorer spark and you may even get more misses. The less you bend the electrode the better and the BKR6E-II are the exact same plugs with a larger gap which means less bending for you.

08-05-2012, 09:07 PM
I wasn't trying to start anything...honest. [;)]

08-05-2012, 09:22 PM
Agreed...but from what I read it's not a good to run these plugs (or others?) at a gap like 0.032" because the 2.0T coils give a much stronger + hotter spark than the 1.8T coils...

So what should I gap them to exactly? Anyone else? Maybe 0.038" or something? 0.036"??

Thanks for the input guys.

08-05-2012, 09:30 PM
Gap 'em up, son. Going to .038 would probably be fine. Use your own judgement there. If you want to go higher, you should really just get the larger ones to start, though.

08-05-2012, 09:38 PM
Thanks. Yeah I didn't know the gaps were so high with these 2.0T coils...

08-06-2012, 06:54 AM
You want to gap them as wide as the car will allow, once you start getting blow out you then lower the gap slightly. The wider the gap the larger the spark because your increasing the resistance. Every car is going to be different so you need to gap them for what your car will allow.

08-06-2012, 07:47 AM
Great. Thanks Mike.

I guess I'll have to do some trial and error...I guess the safe limit for bending the plugs is 0.08" or something? Anymore and they won't be parallel anymore as walky said?

08-06-2012, 08:17 AM
Just have to see how it sits when you gap the plugs you have, if they become bent too much then you might want to go with the plugs that can run a larger gap.

08-06-2012, 11:23 AM
You don't have to disconnect the battery, as far as I know.

08-06-2012, 07:56 PM
Alright so a little update:

Tonight I installed a temp boost gauge off the FPR, a 710N, put in the new BKR6E's gapped to 0.040" (they looked pretty parallel at that height), and the chipped ECU I got off a member here (verified by Christian @ 034 as being APR chipped...although he was unsure of the stage; seller said stage 1)

I went out to test drive the car and it seems that the car only boosts to around 12psi. Now, either I have a problem with my boost gauge (which is possible), or there is something else wrong. Any ideas?

I think I remember that when I got my Passat chipped there was a learn "stage" to it...is that how it works with these programs? I thought it would always boost to full boost on the first go, though.

I have VAG COM but didn't do any logging yet.


P.S. I also found something strange after I hooked up my boost gauge and went for a test drive (before I installed the ECU), I was looking around at the vacuum line that comes off the DV, and the other end was just lying in the engine bay, not even attached to it's specific fitting...no idea how the damn thing was still working...but anyway it's fixed now.

08-07-2012, 06:41 AM
Is the APR chipped or flashed? If there is an actual chip board that has been soldered into the ECU it could be that it is in "stock" mode which is what the APR program will do when it is plugged in or powered up for the first time. 12psi is pretty much what your 2001 comes with for stock boost.

08-07-2012, 10:42 AM
It's literally chipped. Check the installation of the N75 valve. I once had the tubing mixed up and was limited to ~12 PSI on that ECU. Once I corrected the tubing configuration, I spiked to ~19 PSI and settled around 17 PSI with that ECU. This may or may not be the same issue for you, but worth double checking.

08-07-2012, 12:08 PM
Thanks Mike and Nate.

I definitely felt an improvement after installing those items (more power for sure), just not sure if it's running at it's maximum potential yet. So maybe it's been running slow all the time because the DV vacuum line wasn't hooked up? Then I plugged it back on and now it's running how it should at "stock"?

Nate do you remember anything as Mike said about it being in stock mode when first powered up? Or was it always boosting fine for you the first time you put it in?

I'll check out the N75.

EDIT: Checked the N75...a little crusty....but seems OK?

Also went for a little drive again...I am now positive the car won't go over 12psi!!! [=(]

08-08-2012, 10:37 AM
Well just did a log with VAG COM and something is definitely wrong...not my boost gauge.

ECU is requesting ~17psi, car is making ~12psi...

bleh :(

08-08-2012, 11:01 AM
Can you swap in a known working N75 from a local to try out?

08-08-2012, 11:30 AM
Yeah maybe I'll try taking the N75 out of my dad's AWM Passat and see if works. On ECS there's an E revision and a J revision, and the J is twice the price...which one is better?


Damn the price of these things is whack...

08-08-2012, 12:26 PM
Go with whatever the latest version of the OEM replacement is. Do NOT get the "race" version.

08-08-2012, 12:34 PM
Thanks. Just wondering why they still have the "E" version up there...

Just did some more logging.

Did a couple WOT pulls in 1-2 gears, MAF readings never got above ~110g/s...maybe needs a cleaning.

Also, "Boost duty cycle, 0-100%" (which I believe is the N75 valve), went to 95.3%...

08-08-2012, 01:14 PM
Crap posted on the wrong account, sorry. That's me above.

EDIT: Cleaned the MAF, no change...

08-08-2012, 06:13 PM
From your data, it appears that the ECU is commanding the N75 valve to close off so that the turbo will achieve 17 PSI, but you're clearly not achieving 17 PSI. Since there is no position feedback from the N75 valve, you can't really tell what it's doing. At this point, I would consider your N75 valve suspect. Try swapping with the other AWM and see if there is a change.

As a point of reference, I data logged ~175 g/s with your ECU. Only mods were 034 3" HFC, 034 3" exhuast, ER hard pipe TIP, and BPi flow stack with a 6" to 3" "fat" cone filter.

08-08-2012, 06:32 PM
Thanks Nate. It's not at 95% the whole time... only sometimes. Here's the full log:

Is it possible to use the N75 from my '99 Passat 1.8T (it's currently parked and would be better for me instead of taking apart another car)? That car is also tuned and it builds boost fine. Do you think they're compatible? I checked on ECS and they don't seem to list anything for years/engine codes/etc.

I haven't done a log after I cleaned the MAF so I'll see what it goes to tomorrow.

08-09-2012, 09:02 AM
Give it a try. Slowly build up boost pressure. If the pressure begins to spike, just let off. I'm not sure if the earlier model of N75 are reverse or direct acting, so be careful in case they switched from AEB to AWM. Worst case, if they switched, then the N75 will do the opposite of what your ECU is commanding it.

08-09-2012, 03:26 PM
Oh okay thanks Nate. Max@034 said they were different but it can be used for testing purposes [confused]

Anyway, I did another log just now and it seems after cleaning the MAF it will only read 127g/s at max. I guess this could be caused by the fact that it's only boosting to 12psi, so 170*0.8 = 136g/s which is close to the 127g/s I have. AKA it's running at or near stock boost so I'm getting close to stock MAF readings caused by the N75 perhaps as we've been saying?

Thanks again,

08-11-2012, 12:51 PM
Alright so I just took the N75 out of my Passat (what a PITA...Audi is going to be an even bigger PITA...), of course the part # is gone because of rust (awesome design). I'm looking at the N75's on ECS and see that between the E and J revisions, the one barb is long on the E revision, but on the J revision, the opposite barb is longer. Does this make a difference in the way it hooks up?



Mine looks like the 2nd pic above (E revision).

Also, anyone use the ECS race valve? It's considerably less expensive than the J valve...

08-11-2012, 01:07 PM
Don't use the "race" valve. It's junk. Your ECU will have very poor control over that valve.

08-11-2012, 04:01 PM
Thanks Nate. Well I switched in the N75 from my Passat which is a working N75 (Unitronic stage 1 Passat), and still zero change. Still boosts almost the same...[=(]

Anyone have any other suggestions?

EDIT: I also noticed that the pancake valve that goes onto the TIP had a bunch of crap in it (rust chunks)...maybe from the metal tube that it attaches to? I don't know...but anyway I think the pancake valve might be finished...would that cause this?

08-11-2012, 04:50 PM
What is the condition of the pneumatic tubing that connects to your N75 valve? Check for leaks.