16v Digifant 1 FAQ

[88Jetta]

for all you CE2 people

don't forget to get a 5 pin "Digifant Relay" from a corrado

in a pinch you can use the 4 pin relay that can be found on any golf/jetta, and jump terminals 86 and 86a (IIRC) with a piece of wire

otherwise the swap is straight forward

1-- unwrap the wiring harness
2-- pull unneeded wires (oil breather warmer, fuel after run pressure sensor/relay, etc...)
3-- resort wires
4-- shorten the wires to 16v specs by de-pin the connectors, undo the crimps, shorten wires, re-crimp, and re-pin
5-plug in plugs F, G1, and G2 to the fusebox. There's a thing on the end of the fusebox that you pull to make all the plugs loose by unlocking them

Ross machine fuel rail and aeromotive adjustable FPR:
the FPR fits on the passenger side. I think the BBM fuel rail is longer on the drivers side, so maybe you can fit the FPR there

[OhioBenz]

anyone have apart number for new pins for the sensor connection ends????
I have an AMP/Tyco connection so I could get them in bulk for everyone ..............

[88Jetta]

Schweetness

I remember I found the part number one time on a german distributor website. I'll go see if I can get a part number off a connector in the garage.

[OhioBenz]

either the connector AMP part number or the individual pin part number will work

[88Jetta]

this is the babelfish version that I found in my favorites folder

http://babelfish.altavista.com...3b%3b

or go to http://wueko.wuerth.com
Kabelverbinder VW
or the part number 0964 558 98

let us know what the cost is on one of those kits.... or even just a whole bunch of the smaller pins for sensor/switch connectors..... it sure beats having to dish out $1 per single connector at futrell's

[OhioBenz]

i'll have to show a terminal to an Amp rep - those are all VW numbers. tried to cross reference them but nothing came up.

[88Jetta]

someone sent me a PM... since I'm not on my computer now I can't reply (security stuff, don't wanna change their settings)

Explanation of the digifant relay when doing a CE2 swap

Digifant relay is just a relay that gives power to the ECU... kinda like a fuel pump relay or something. All digifant cars (1 and 2) had relays, digi 2 has a 4 pin relay, digi1 has a 5 pin relay. The difference is just that the 5 pin relay has another pin that sends out power to another circuit (86a). If you have to use a digi2 relay, you can use a jumper wire and bring power from terminal 86 to 86a, which I forget how it's marked on the relay board (30 or something?), but it's the small pin on the lower left. The relay goes in slot #3 of your relayboard (top row, 3rd from left)

The part number for the digi 1 relay is:
165 906 381
it's like $10 at the dealer, sometimes in stock... dunno if it comes on any other cars or not

[OhioBenz]

I've read some posts where it was stated that Digi-1 CO Pots did not fare well in NA applications (i.e. it gets sucked into the inlet because its made for boost-not vacuum). I'm building a fairly modded NA 2.0-16v for my GLI and plan to run Digi-1. Is anyone aware of this potential issue?
Is anyone running a different IAT than the G60 VW one?

My custom intake is about 80% complete - is there a certain distance from the head that the IAT is supposed to be located? My intake runner length is 17" (optimum for 2.0) with a Ford twin 58mm TB. I had planned to use a short adapter and then a K&N. For Digi-1 should the IAT be located ahead of the TB or does it matter??

[88Jetta]

Quote, originally posted by OhioBenz »

I've read some posts where it was stated that Digi-1 CO Pots did not fare well in NA applications (i.e. it gets sucked into the inlet because its made for boost-not vacuum). I'm building a fairly modded NA 2.0-16v for my GLI and plan to run Digi-1. Is anyone aware of this potential issue? Is anyone running a different IAT than the G60 VW one? My custom intake is about 80% complete - is there a certain distance from the head that the IAT is supposed to be located? My intake runner length is 17" (optimum for 2.0) with a Ford twin 58mm TB. I had planned to use a short adapter and then a K&N. For Digi-1 should the IAT be located ahead of the TB or does it matter??

I forget the exact distance, but the CO pot should be located within like 6" or so before the throttle body. Mine is located by the back corner of the timing belt cover (by the shock tower)... so it's fairly close. You should point the connector so that faces towards the throttle body, making it paralell with the airflow.

I've put a few miles on my car in it's normally aspirated digi 1 state.... no problems with the COPot getting sucked in. When you make the copot bung make sure that the O-Ring squishes down a little (IE not flopping around). I forget the exact sizes, but electrical conduit has two sizes pretty close to two diameters of the CO Pot, the skinny part and the thick part. IIRC it's like 3/4" and 1" conduit, but I forget.

Here you can see how the smaller conduit will squish the o-ring up against the copot, and the large diameter allows the clip to push down against the o ring. Note that these were cut long so that I could trim them when installed. I was thinking of drilling a few small holes through the larger conduit and plug welding the small piece to the large piece once everything was installed.

[OhioBenz]

i'll probably machine one out of aluminum - so if i mount the Co pot directly after the K&N it should be OK?
remember Im running a huge TB so no standard VW hoses/tubes to connect here

[88Jetta]

I would guess so..... I just remember reading some spec somewhere (bently?), that is probably more applicaple to boosted applications where a change in piping, or the intercooler can make a huge diff. in the tempurature.

I bet that as long as there are no major tempurature changes anywhere on the intake pipe that it makes no difference... it's not like it's the MAP sensor or anything and a slight change in location changes the amt. of vac.

[OhioBenz]

that raises another question - I built a custom intake coming off the OEM 16v lower intake flange. The old airshroud passage is still there - can that be used for MAP vacuum or should I tap in behind the TB?

[16VJohn]

Quote, originally posted by KingofNod »

Any of you Digi 1 NA guys have problems with emissions testing afterwards? Mine is going to be driven on the street, so I have to make sure it will pass when the time comes, since my car isn't too slammed for the test dyno

just dump 8 bottles of octane booster in your tank, and make sure your 02 sensor is working

[valet]

i just got my 16v swap done in my corrado but when i start it up i get an absurd amount of white smoke coming from between the firewall and the back of the head/block. cant tell where it is exactly coming from

[PeOpLeG60T]

spilled oil on the manifold and/or downpipe? something looks like burning from the manifold/downpipe heat

[valet]

dont think its spilled oil... looks more like its coming from the place where the header comestogether (at the branching part where some parts overlap) or from the gasket that goes to the cat

[88Jetta]

it's normal for your exhaust manifold to smoke for 30-60 minutes after you handle it with greasy hands, making the manifold all greasy, so when it heats up it smokes. After that, it may stink for a week or so

[valet]

thing is, all that was installed before i got the car... gues someone had some REALLY greasy hands

[KingofNod]

Also, if you took the motor apart, or even the head, and replaced the headgasket or other gaskets, it will smoke for awhile while things break in. Mine did the same thing both times I've changed the headgasket. Oil and coolant that got into small areas if you pulled the head also burning off.

Anyone with Digi 1 having problems with oil comming out of the oil filler cap? Its on tight, and am wondering if its the cap, or if theres too much pressure?

[WaterWheels]

Kind of like the robot Number 5 in the movie, I am looking for input. I have been thinking of the Digifant I or II conversion for a 16v engine for some time. I have also read all the posts here and it seems that at least a few are happy with the results of either system. Because I have not decided which route to take, I am posting this in both forums, sorry for the space I used, forgive me. In an effort to keep this as short as possible, I will skip the reasons as to why I am thinking about this conversion and just ask for the input needed.

Some background that might help when giving advice. I am currently running my 16v (1.8L) with a straight CIS setup. No CAT as I don’t have to currently have one. Fuel mixture unit is the VW Motorsport model. Fuel pump is 52mm CIS-E from a PL code engine. 43mm intake manifold, Autotech sport camshafts (I place it between the Schrick 260° and 268° cams) and a modified cylinder head, was told about 12% - 15% increase in flow. Current exhaust is European factory non-emission except the rear muffler is an Italian sport model. I have no problems doing wiring and already know the requirements needed for either system If that’s not enough information, feel free to ask.

Here’s the sticking points or questions:
> I know the Digifant I can be chipped to run a normally aspirated 16v engine. I assume not only the fuel, but the ignition advance is also altered to work or the conversion would not function real well. What about the Digifant II ECU? Can the ignition advance also be corrected? Can the fuel shut-off, limiter, also be raised? What about the different ECU models out there, KEN, Bosch, TAN, Seimens all with a dozen suffixes or so, which is the best for doing a Digi II conversion?

> The air flow meter, Digi II only here, which really is better. I have read the debate about the BMW big meter vs. the VW meter. I have also looked at them and a few others, Ford and Opel, to see what all the differences are. The BMW has a tight spring as does the small 6 cylinder BMW meters. Except for the big BMW meter, they all had about the same size in and out openings. The pins and their function don’t match the VW positions and functions either but of course the wires can be swapped easy. The size of the openings is also an issue I really don’t understand the big deal about. The big BMW is like a 3.2L or bigger 6 cylinder so I would expect the meter to be larger, but the smaller 2.5L 6 cylinders use the same size meter as the 1.8L and 2.0L VW engines, what gives here?

> Co_pot position and mounting, Digi I only here, is another issue. The original G60 has the co_pot mounted in the air inter cooler and air temperature there is not all that cool. The correct position, direction, I know but what about distance from the throttle body? Is it going to be too cool for N/A usage or is the chip going to correct for this if it is a problem? As I understand things, the co_pot has a much greater effect in this application then when using boost so is position important?

I know there are aluminum and steel mounting bungs. I have also seen the self made bung posted. How are either of these attached to a plastic or aluminum air pipe? A steel pipe I don’t think I would use because of the weight. Can the water flange sensor bungs, plastic kind like the co_pot bung, be cut off and mounted to a plastic air pipe?

> The fuel pump/injectors/regulator is the last area I would like some input on. I currently have a good set of G60 injectors. Will they be good, at least for starters, or should another set be purchased?

I also have a “normal” 3BAR regulator. Again, will this work well or should I spend the $70 or so and get the 3.5BAR model?

As stated, the current fuel pump is the 52mm CIS-E model. I don’t mind buying the G60/Digifant pump as I already have two of the housings and filters, but can the higher pressure pump be kept? Will it over-power the regulator and either ruin it or flood the engine?

Sorry to take up so much space but I think some of the photos that people post take up more than this any how. Some helpful advice on these issues will help me decide which system I will use. This is also not a race car so keep that in mind too please. If anyone can relay just how they feel about the driveability/performance/satisfaction of their conversion that would help too.

Again thanks for any helpful advice or clearing up.

[KingofNod]

I'm having some issues with my Digi 1 to Motronic swap. The car is running now, and runs very well. However, I seem to have a dead spot right at 2100-2500 RPM's. Once you get above 3K, its great. However, at that 2100-2500 the car looses a lot of power, and bogs till you get passed that point. Any ideas on what it could be? Is it just needing to be properly tuned, or is it some sort of leak or timing related?

[E60]

Quote, originally posted by KingofNod »

I'm having some issues with my Digi 1 to Motronic swap. The car is running now, and runs very well. However, I seem to have a dead spot right at 2100-2500 RPM's. Once you get above 3K, its great. However, at that 2100-2500 the car looses a lot of power, and bogs till you get passed that point. Any ideas on what it could be? Is it just needing to be properly tuned, or is it some sort of leak or timing related?

Timing related? check the timing and you'll know.. make sure to pull the CTS first, set it at 6btdc. Are you running the stocker chip in there? 3 bar fpr? throw out some specs for the sake of the FAQ.

[push]

will a Digi-1 automatic ECU and harness work? I have an ABA 16v turbo running only about 6 psi of boost. This car NEEDS to run within 2 weeks and I have a full automatic corrado G60 harness and ECU and all necessary parts sitting in front of me. are there any major differences in the harness? Also will the ECU in stock form be able to make this thing run? I plan on getting the car chipped but will a stock ECU be enough to get this car up and running safely enough to drive for about 2 weeks?

[OhioBenz]

iirc the auto uses a different TB that has a tps sensor vs the manual ips+wot.

i dont think the digi-1 is good enuf for 16v-T - get an SNS chip made!!

[KingofNod]

Quote, originally posted by E60 »

Timing related? check the timing and you'll know.. make sure to pull the CTS first, set it at 6btdc. Are you running the stocker chip in there? 3 bar fpr? throw out some specs for the sake of the FAQ.

Running 3.5 BAR FPR, with SNS Stage 5 chip designed for NA 16v applications, and tuned for the mild cams that I have. I'll have to check ignition timing, and can't think what else it could be other than a bad fuel or ignition map, and if thats the case, there isn't much I can do other than get a different chip.

[ValveCoverGasket]

Quote, originally posted by OhioBenz »

i dont think the digi-1 is good enuf for 16v-T - get an SNS chip made!!

stock chip is decent, but keeping it out of boost for the most part will definetly save the motor. the fueling goes all wonky when the boost hits, or you hit WOT

[PeOpLeG60T]

Quote, originally posted by OhioBenz »

iirc the auto uses a different TB that has a tps sensor vs the manual ips+wot. !

are you saying that the standard harness is equipped with bot connectors? tps and the switches? i imagine so

do you think that ,with a manual engine digi1 management , we can hook the TPS connector to a tps and do the work of the switches??

i guess the ecu wont even take care of the tps input if he's programmed to work with the switches ......

i got a problem that i need to solve

i have now a VR6 TB on my custom 16v intake and i want to know if i really need to hook the switches on brackets n' stuff or i can plug the tps connector on it
only want to know .. could be easier this way
thanks

[OhioBenz]

it would be interesting to see if the harness from a digi-1 auto would hook with the VR6 TB tps. I' putting a Ford Lightning TB on one will have to adapt the manual switches to it somehow.

[E60]

Quote, originally posted by KingofNod »

Running 3.5 BAR FPR, with SNS Stage 5 chip designed for NA 16v applications, and tuned for the mild cams that I have. I'll have to check ignition timing, and can't think what else it could be other than a bad fuel or ignition map, and if thats the case, there isn't much I can do other than get a different chip.

doubtful. Your co-pot or your timing is prob. off... All of your gear in good shape?

[PeOpLeG60T]

anyone ever tried the TPS trick?

the digi1 runs with no switches but idle isn't perfect and no WOT enrichment who is bad when pushing air in from a turbine i dont want to melt anything

[E60]

Quote, originally posted by PeOpLeG60T »

anyone ever tried the TPS trick? the digi1 runs with no switches but idle isn't perfect and no WOT enrichment who is bad when pushing air in from a turbine i don't want to melt anything

hook up your switches man, that means you don't have a deceleration cut-off, not to mention no WOT

[PeOpLeG60T]

only wanted to know ... my engine isn't running yet still have time to hook the switches thanks

[A2Carat]

Ok, from what I read, I gather this much...

My 2.0 16V Passat motor with CIS-E Motronic can be dropped into my 90 Golf Digi1 8v by just switching the injector cups on the 16v and the Digi1 ECU chipped with an SNS calibration? (web address for SNS?) Both are 5 speeds.

Is this correct, or do I need to get some other things? Do I really need the co-pot? I am keeping this system NA.

[OhioBenz]

new fuel rail
new fpr
plug off the cold start injector hole
CTS sensor - choose 16v or Digi - either rework harness or adapt digi coolant inlet onto head
the tps and wot switches may be different between digi and Passat TB's
some people run idle control valve, some dont
venting of the block
plug air shroud channel

[A2Carat]

Quote, originally posted by OhioBenz »

new fuel rail new fpr plug off the cold start injector hole CTS sensor - choose 16v or Digi - either rework harness or adapt digi coolant inlet onto head the tps and wot switches may be different between digi and Passat TB's some people run idle control valve, some dont venting of the block plug air shroud channel

And then everything is good? What FPR am I to get?