"Standalone" Fuel Management Install - DynoJet PowerCommander for 1.8T

[Rusty]

Well, I finally did it and installed the DynoJet PowerCommander PCIIIusb. Complete fuel mapping vs. boost, in 250 RPM increments. For those of you that haven't been following this, it's a "poor man's" way of precisely controlling fuel to our engines. Many Thanks to Shawn Fogg for his pioneering Internet writeup that got me started. If any of you are interested in doing this mod, you need to read his writeup: http://ackthud.com/shawnfogg/fuelupgrade.htm. I read it two years ago, but was young with my car and scared of splicing critical wires. Two years of fighting my ECU for every last drop of fuel gave me enough courage to finally forge ahead and just DO IT.

Briefly, the PCIII sits between the ECU and the fuel injectors. The ECU still controls when the injectors fire, but the PCIII controls how long the injectors fire, on a +/- percentage basis vs. the ECU's fuel pulse. The PCIII uses the TPS (Throttle Position Sensor) signal to trigger the extra fuel, but I connected a MAP sensor to the PCIII's throttle inputs to get fueling based on boost. It would not be a good idea to use TPS on our turbo cars - too much variability of boost vs. TPS. Note that this does NOT constitute MAP-based fueling. The base fuel pulse is still determined by the ECU as a function of MAF - the PCIII just modifies this pulse based on the additional boost. The astute reader will instantly realize that this is the only "add-on" way to defeat the 16.32 msec duty-cycle limit on the AEB engine. Piggy-Back units can't do this, at least not the ones I've researched (SMT, Split-Second). Chip tuners can't do this, either - the 16.32 ceiling is in ROM where they can't (or won't) get to it.

NOTE: the PCIII requires high-impedance injectors, which all B5's and B5.5's have. If you try this mod on a different car, be sure that your injectors are high-impedance a.k.a. "saturation" injectors, between 12 and 15 Ohms. Low-impedance a.k.a. "peak-and-hold" injectors will have values around 4 Ohms.

Shawn used some resistors to make sure he didn't throw fuel injector fault codes. I contacted the mfr, who strongly hinted that with the newer model I was using, I should try it first w/o resistors. When I first fired it up, I got one "intermittent ground" code on each injector, with no CEL, and after clearing codes, they have not come back. These codes were no doubt due to initially wiring the PCIII to a "run-only" power source, instead of "run/start."

The total cost was $250 plus shipping and some chump change for things like the rubber firewall grommet. I got the MAP sensor and Molex connectors as free samples straight from their websites.

Overall schematic:



Here is a full-resolution, full-sized JPEG: http://home.comcast.net/~rragan7540/...CIII/PCIII.jpg

If you'd like the original Visio file, PM me and I'll email it to you.

Parts list:

DynoJet PowerCommander III USB model 315-411 (for Suzuki GSXR-1100)
$250 from Illinois Dyno Center http://www.idc-solutions.net/PowerCommanderTuning.html

Motorola MAP sensor MPX4250AP
free samples from www.freescale.com

Molex connector housing 52213-0311
Molex crimp connectors 50148-8000
free samples from www.molex.com

Rubber Grommet, 3/4" OD, 7/16" ID
NAPA part no. 784632

Assorted wiring, connectors, wiring tools, and wire nuts. I was lucky that I could borrow the correct Molex crimping tool from work.

For the connectors used in the Barometric Pressure Circuit, see:
Barometric Pressure Mod yields 10% HP/TQ gain and Adjust Timing using Barometric Pressure Circuit

Original PCIII connector, designed to plug-and-play with the Suzuki GSXR wiring harness:




The PCIII after removing the Suzuki connectors and all un-needed wiring:




Here's what I had planned to do - have small Molex connectors on the PCIII and the FI harness, so I could just "plug-and-play" and have it easily removable for troubleshooting or "back-to-stock" purposes. Great idea except when I got ready to do the FI harness - the wiring gauge was slightly too big for the Molex pins. Using a bigger connector was not an option for me because it would have required a huge hole in the firewall:




Here's my workspace including the orange-handled Molex crimper. I was still able to use it because the MAP sensor pins perfectly matched one of the Molex connectors. You will note AA's writeup on how to add a fused, switched wiring link to your car (Adding fuses to your fusebox and relay plate). Unfortunately, the terminal 75X used for a power source in that writeup only works in the "RUN" position, and I realized this only after I tried to start it. I had a few anxious moments and a couple of emails to Shawn until I figured out the issue. The PCIII needs power during "START", too. Doh! He even said so in his writeup. Doh! RTFM...




The FI harness splice. You may think I'm nuts to use wirenuts, but I wanted easy uninstall and troubleshooting, and soldered joints don't do that. I may solder them someday, but not today:




The best location I found for the PCIII was the backside of the ECU inside the ECU's protective box. You can also see the MAP sensor location in this pic, as well as the infamous BPM (Barometric Pressure Mod). The BPM gave me pre-made connections for MAP-sensor power and ground. Without the BPM, you'll have to splice into the BP wires directly - either that or the TPS wiring - the MAP sensor needs a 5V reference and ground. You can also spot the USB interface cable from the PCIII, which runs through ECU access hole, where it spools nicely under the dash with its little head sticking out the unused rectangular hole behind the OBDII port. It extends all the way across to the pax seat. Very nice.




Here are the final views, everything buttoned back up:






The most time-consuming part of this mod was the under-dash wiring, installing Kathy's great mod that I didn't use. Oh, well - I left it in there, maybe I'll use it for a radar detector or something. While I was under the dash, I re-did all the grounds and re-routed and cleaned up my gauge wiring. Since the power source for my gauges was START/RUN and has proven reliable, I just tapped into it for PCIII power (wirenuts again!). I had wired my gauge ground direct to battery, one common wire wire-nutted to the four ground wires for the gauges - so I just added the PCIII ground to that. Overall it was pretty simple.

Calibrating the MAP sensor to PCIII throttle position was easy and fun. The MAP sensor is good to 25-30 psi. I'll never run more than 20, so that's what I calibrated to. Set the zero position with car not running - atmospheric. Disconnect the boost line from the manifold and stick it in a bike pump. Pump to 20 psi by the boost gauge, set 100% throttle position. I like this scale because it is easy to correlate to boost, just multiply by two and drop a zero, e.g. 10% TPS = 2 lbs, 40% = 8 lbs, 100% = 20 lbs.

Note that the PCIII power ground is different than the PCIII TPS ground. Be sure not to get them confused. The power ground has two silver bars, the sensor ground has one. Note also that this install did not require any intrusion into the ECU's wiring harness - I really like that.

First impressions? FABULOUS! I'm already on my second-iteration fuel map. I'm running stock boost right now, but even at that I was getting double-digit knock retard at WOT. With the PCIII I've added over 20% fuel to the knock-retarding RPM ranges w/o affecting LTFT (Long Term Fuel Trim). I plan to completely dial-in the stock-boost fuel map before I put my MBC back in and add extra boost. This is so Awesome. I'm so happy - this is much better than the ham-fisted Cartech approach, although the things I learned with the Cartech have enabled me to use the PCIII to full advantage, quickly.

Thank You, Shawn, for your write up, and thank you, DynoJet, for a great and useful product.

*DISCLAIMER - this post is provided for information only. Any information used in this post is done at your own risk. Verify everything before proceeding. DynoJet does not design the PCIII to be used on automobiles and discourages such use. Using the PCIII as per this writeup will VOID the PCIII warranty and your car warranty.*

This will of course go into the Info Forum after being fleshed out in discussion.

[pacent]

WOW...thats awesome...first Passat with full standalone

What are you using to tune? Wideband 02? stock narrowband? EGT?

[ONE8T]

Fantastic setup! I had one question....

Note that this does NOT constitute MAP-based fueling. The base fuel pulse is still determined by the ECU as a function of MAF - the PCIII just modifies this pulse based on the additional boost.

Could you run the same type of additive map off the MAF signal? It may sound stupid since the fueling is already run off the MAF input, but since all you're trying to do is beat the pulse limit, that would still do it right? I'm thinking if something went wrong with your new map sensor, you could go lean really quick and that thing isn't in any other feedback loop. Does that make sense?

Great work.

[jikozi]

Sounds like you did a hell of a job on this. Even though i admit to not understanding some of what you did, it sounds like a nice way to squeeze more fuel out of the system. You're a brave man, I'm glad you got everything to work.

[Spanky McGee]

Whoa. I have to read this when i've got more time, but initial impressions are:

"I wish I were smart enough to hook that up to my car"

:o

[O22Ripper]

Good ole Rusty. Puttin his brain into it! This man is a genius!

[D.Passat00]

wow...that's just amazing what you did. glad you got it to work well for ya.

[Rusty]

Originally Posted by pacent

...What are you using to tune? Wideband 02? stock narrowband? EGT?

Right now I'm using knock retard - add fuel until it disappears. The narrow-band O2 sensors are a double-check - if it takes more than .89 volts in 4th gear to get rid of the retard, then I'll have to revise my tuning methods. On cylinder 2, my best cylinder (little or no retard), it's going to wind up too rich, so once I get the overall map dialed in, I'll go back and use the cylinder trim feature to lean out cyl 2 to match the others. And also, say, if I get 3 cylinders with no retard, and one pesky cylinder remains, then I can trim that one richer. This is so cool...

I can't believe how much fun this is and how much better the car is already running with some precision fuel control.

I may eventually get a PLX devices wide-band, but this is good enough for now. With as much of a lock as the ECU has on closed-loop operation, I'm not sure I'd get that much advantage out of a wideband unless I go Full standalone, where I could control closed-to-open loop, timing, etc. And I'm gonna fix up the 'rocco before I do something lke that.

[Rusty]

Originally Posted by ONE8T

...Could you run the same type of additive map off the MAF signal? It may sound stupid since the fueling is already run off the MAF input, but since all you're trying to do is beat the pulse limit, that would still do it right? I'm thinking if something went wrong with your new map sensor, you could go lean really quick and that thing isn't in any other feedback loop. Does that make sense?...

Yes, that makes sense. The TPS inputs to the PCIII need to be a 0-5V type of signal. If the MAF signal is compatible, I don't see why you couldn't use it. But I would be very nervous tapping into the critical MAF signal wiring. Setting appropriate min and max points would be hard. And tuning the fuel map would be harder - you'd have to be a datalogging madman. And I think it would be harder to keep from mucking with closed-loop operation. The MAP sensor is simple and I like simple, but if one is willing to have it more complex, then MAF might be a better idea. (wheels are already turning... )

For some reason I have no fears whatsoever that this MAP sensor will fail. I do have a spare, though.

[Rusty]

Oh, yeah, and did I mention the "accelerator pump" feature?

[Chas]

I think I said this to way back when: "Why don't you just get a chip?"



That's so totally cool Rusty!!! And we are all so lucky to have someone like you here with us At CB5/PW!!!

You've got to be in heaven right now! So how much longer are you going to be tuning in the stock system? I understand why you need to do that first before the MBC goes back in, but hey, we want to here about the really good stuff to come!!

Way to go man, way to go!!!

[Chas]

PS, when are you getting a K04??

[Rusty]

Originally Posted by Chas

I think I said this to way back when: "Why don't you just get a chip?"



That's so totally cool Rusty!!! And we are all so lucky to have someone like you here with us At CB5/PW!!!

You've got to be in heaven right now! So how much longer are you going to be tuning in the stock system? I understand why you need to do that first before the MBC goes back in, but hey, we want to here about the really good stuff to come!!

Way to go man, way to go!!!

I'm glad you posted, Chas - it reminds me to post this at RMCB5.

Yeah, I'm in heaven right now - tuning heaven, anyway. I just tossed in a 3-bar FPR for better atomization (vs. 2-bar), which dropped my LTFT to -8%. So I just readjusted my entire map by -8% which will (theoretically) bring the trims to zero. Sweet.

Yeah, this is why I didn't get a chip!!!

I'm staying stock until I get it dialed-in perfect - all knock retard gone, all cylinders trimmed even. Min one week from now, max two weeks. Then, whatever I add on top of that will be gravy. Don't worry, I'll be at full boost for the GTG... (vrrroooommmm...) too bad it won't be track-ready. I need new CA's, engine mounts, tranny mounts, PCV overhaul - and O2 sensors. And did I mention tires?

[pancreas]

you could start your own Passat tuning company...rusty's house of boost

[dutch-mountains]

Wow, I wished I had the knowledge

I'm going to read all your follow-ups on this, very curious about gains in hp&torque.

[SausageRocket]

that is awesome Rusty! I love the mod

but wouldn't it be easier to order a euro spec ECU to get rid of the 16.32 msec duty-cycle limit?

[pete1]

Rusty!

[HermanH]

Russel, you comin' to ND Show again? I WANT to see this thing in person. You've finally given me some hope on the K04 issue!!!!!

Now if you could only apply the same strategy on your family problems...who, way OT (yea, dial out that delinquent!!!!)

PS:

Drop by my house in the AM (7am); baisee and shmove is comm' over to wash the cars before the show.

PSS:
Just re-read the post again; no intrusion into the ECU???? Ok, you sold me. The Cobra can wait!!!

[Rusty]

Originally Posted by Chas

PS, when are you getting a K04??

Maybe never. I might go straight to something like a GT25R... I'll cross that bridge when I get to it. I need to start researching now so I'm ready-to-buy when the K03 gives out (125K and counting...)

Originally Posted by pancreas

you could start your own Passat tuning company...rusty's house of boost

If I could hack the ECU, I would. All this add-on stuff is great for me, but it would be so much better for most folks to be able to do this directly to the ECU. I'd design software that would let people do it themselves.

Originally Posted by SausageRocket

...but wouldn't it be easier to order a euro spec ECU to get rid of the 16.32 msec duty-cycle limit?

I dunno, somebody tell me. I can think of lots of potential problems, plus I still wouldn't be able to create my own fuel map.

Originally Posted by HermanH

Russel, you comin' to ND Show again? I WANT to see this thing in person. You've finally given me some hope on the K04 issue!!!!!

Oh, I wish! Those OT comments about my family life are exactly why I can't come... But the new addition to the family is doing much better. He's finally getting his head out of his ass, and that makes it all worthwhile. But there's really not a whole lot more to see than what I've shown here - it's pretty simple. If you'd like more pics, I can email you a few extras. And of course, if you try it, I'll be there for you... I think this mod would be perfect for you. Do it. DO IT!!!

[Rusty]

BTW, the Bentley spec for fuel injectors is 12-15 Ohms. It doesn't call out a different spec for the DBW cars, so I have to assume that the DBW cars have high-impedance injectors, so this should also work for you DBW guys.

[BKVR6]

So I can take the PCIII off my R6 and plug it into my Passat! More uses for the PCIII cool.

Good work Rusty! Fine tuning at its best!

[dutch-mountains]

Yes, DBW cars have high impedance injectors, just measrued mine all @ 14.1 ohm

[The Dog]

Originally Posted by SausageRocket

that is awesome Rusty! I love the mod

but wouldn't it be easier to order a euro spec ECU to get rid of the 16.32 msec duty-cycle limit?

What the f....? Euro models do not have the duty-cycle limitation?
Great work Rusty. Now I have to rethink me tuning steps.....

[HermanH]

Russ:
I went on the Molex site and with any luck, I should have the connector and pins sent to Cisco; we'll see. Just have to pretend I'm some engineer doing a mobile network project WIFI is quite popular ya know.

In between the quiet periods with SNKVENM, I should be able to get the funds together for all this stuff; it's not that exepensive at all! Your PDF is execellent as is but I'll ping you if I run into a problem. Thanks again.

[scotty_passat]

nice work rusty!

[Rusty]

Final bump before move to Info Forum. Any more questions?

[stealthx32]

Yeah. Question. Why didn't you get a Megasquirt?

[Rusty]

Originally Posted by stealthx32

Yeah. Question. Why didn't you get a Megasquirt?

'Cause this was a LOT easier.

[scotty_passat]

ok lets see the map tables you've come up with so far.

[ONE8T]

Originally Posted by scotty_passat

ok lets see the map tables you've come up with so far.

Does Garrett Lim reveal his programming secrets?