90 Corrado to 96 1Z TDI Swap

[greasyrides]

Car is now for sale. It will be sad to see her go.

http://forums.tdiclub.com/showthread.php?t=461041



Current State of Car Pictures:

I'm far enough into my Corrado swap that I don't feel too embarrassed making a build thread. TDIClub is a great web resource so I figure I can gain a good deal of help and input by posting this build thread.

I'll post my progress pictures on my Picasa web-album, and I'll try to update this thread as I have time. You are welcome to post comments on my web-album here: https://picasaweb.google.com/mstanbro/CorradoTDIBuild?authuser=0&feat=directlink

Plan: The plan is to have a daily driver Corrado that I'm happy with. I care about the environment and my wallet, so biodiesel and 50mpg are high on my priority list. I also plan on occasionally auto-crossing the car, so I will eventually do some performance upgrades (suspension to start).

Background: In 2009 I swapped a 1Z from a 1996 Passat into a 1990 Corrado that I acquired for next to nothing. I had it running, but that was about the extend of the conversion. It needed a ton of work everywhere else on the car so it sat for most of a year since I was never really happy with it (lost motivation).
Then in early 2010 I found a very clean 1990 Corrado that was just repainted and had a near perfect body. I don't do body work, so this car was the ideal starting point for me. It needed a fair bit of work after some previous owners had neglected most of the mechanical and electrical problems that plague these cars, but I wasn't too scared off by anything I discovered.
I decided to start over and swap the 1Z into this car, but not cutting corners. I want a daily driver so I needed brakes, suspension, hvac, etc all in working order, and as few Corrado "gremlins" as possible.

On to the pictures (many more posted to my Picasa album).

The Corrado shortly after I bought it. I had already replaced the In-pro turn signals with SLC turns. I swapped all of the 5-lug components to 4-lug since I had brand new EVERYTHING for a 4-lug setup, and the 5-lug was a complete hack job.

All black-tails are already gone. I plan on using a stock G60 tailpipe tip.

Sold the G60, cleaned and painted the engine bay.

Mild rust under battery. Treated and painted.

 

[greasyrides]

02J Shifter Install: I figured this was the perfect time to do the install. The 02A shifter in the Corrado was in poor shape. Reverse and 1st gear were a guessing game, so I found myself always starting out in 2nd to avoid a "woops" moment. I love how precise the 02J in my MkIV feels, so I knew I wanted this in the Corrado also. I'm using the stock 02A transmission that came mated to the 1Z TDI, but I installed the shifter tower/weight from a 02J.

Tunnel modified for 02J shifter.

02J shifter installed.

Reverse position. I had to notch a good bit of the driver-side of the tunnel.

MkIV boot.

02A tower on Left, 02J on Right. The shift weight interferes with the intercooler piping, which I have yet to figure out.

 

[greasyrides]

HVAC: I originally had no plans of working on the HVAC in the car, since I did not want to pull the dash. I soon realized that it is nearly impossible to install the Passat pedal cluster without first removing the dashboard and steering column. Oh well, with the dash out, I could now replace the blown fan resistor and install the R134 evaporator from the Passat. To avoid ever having to do this again, I went whole hog and replaced everything: New HVAC foam, New Heater Core, New Fan Resistor, used Evap from Passat, and used Fan from Passat (best of the 3 fans I had). Removing the heater box also freed up some space for the pedal cluster install and fusebox wiring.

Big ol' mess of heater boxes.

Remaining foam removed from blend/mode doors.

Frostking HVAC Foam/Foil Tape.

Foam Installed.

Rebuilt Box (new foam, heater core, fan resister, updated fan and evaporator)

 

[greasyrides]

Engine Bay/Wiring/Pedal Assembly: Engine wiring is now installed, although I have a few individual connectors to figure out. Pretty certain I killed my tdi instrument cluster with low voltage last year. I'll diagnose this when I try to start it (soon hopefully).

The ever important Spaghetti picture.

Passat Pedal Assembly Installed.

Less exciting things, but equally as important: MKIII K-frame, TRW steering rack, new boots, new tie-rods, stock G-60 sway bar, TDI tranny and engine mount, MKIII (gasser) firewall pad. Non-ABS brake booster and all new hard brake lines installed (old ones weren't horrible, but had several splices).

 

[greasyrides]

Engine Install: Engine slid right into place, I have just enough clearance on the passenger side frame rail, so either I lucked out, or maybe I didn't get the K-frame perfectly centered?

Engine Sitting in place.

Lower radiator support. I wire-wheeled it, rust-treated, primed, and painted. Not the greatest, but the rust is gone and should stay gone.

Homemade EGR block-off plates. Still running a Cat and biodiesel, so mother-nature won't get punished too badly.

ECU installed and grounded.

Backside of ECU.

 

[onlyn8v]

Looks great! The ECU doesnt ground through the bolts though.

 

[Houpty GT]

I saw your pics on the web a year ago. You took your old photos down. It is good to see you are reworking it and bringing it back to life. I have put 25,000 miles on mine but I have been really trying to quiet my Corrado down. The sound deadener on the firewall may be essential to get the low frequence noise at 70-80 mph out. I already have the TDI engine mounts.

 

[greasyrides]

Yeah, the swap was never really drivable in the state I previously had it. Swapping everything to this much nicer Corrado has kept me a lot more motivated...granted I only get about 5 hours a week to work on it. At least it will be done correct this time.

For the firewall sound deadening, I grabbed several from a local junk yard: B4 VR6, MkIII 8v, and compared to a MKIV one while I was still at the yard. I bought the B4 and MKIII pads. I hoped to use the B4 one, since it covers much more of the firewall, but it was cut in a few places and didn't want to stay in place when I test fitted it. The previous owner put a good amount of Dynamat material behind the door cards, trunk, and under the rear seat. Hopefully the Dynamat and firewall pad will keep the cabin fairly quiet.

The car has 3" exhaust with a single muffler. Time will tell if I can deal with the drone. It was a little annoying with the G60, but I will see how it is with the turbo before passing judgement. I have straight exhaust on my Audi 4000, it sounds great for rallycross but it is almost deafening at highway speeds. I don't want that in a daily driver.

 

[GTiTDi]

Yeah, the swap was never really drivable in the state I previously had it. Swapping everything to this much nicer Corrado has kept me a lot more motivated...granted I only get about 5 hours a week to work on it. At least it will be done correct this time.

For the firewall sound deadening, I grabbed several from a local junk yard: B4 VR6, MkIII 8v, and compared to a MKIV one while I was still at the yard. I bought the B4 and MKIII pads. I hoped to use the B4 one, since it covers much more of the firewall, but it was cut in a few places and didn't want to stay in place when I test fitted it. The previous owner put a good amount of Dynamat material behind the door cards, trunk, and under the rear seat. Hopefully the Dynamat and firewall pad will keep the cabin fairly quiet.

The car has 3" exhaust with a single muffler. Time will tell if I can deal with the drone. It was a little annoying with the G60, but I will see how it is with the turbo before passing judgement. I have straight exhaust on my Audi 4000, it sounds great for rallycross but it is almost deafening at highway speeds. I don't want that in a daily driver.

You will find that the turbo does a great job of muffling the majority of the exhaust noise...

 

[G60ING]

Nice project, looks good. Is that the B4 TDI ECU mount? My ecu's post is tilted almost identically to yours

Keep the pictures coming.

 

[greasyrides]

Yup, the ECU is using the B4 mount. I hacked away the majority of it, so all that is left is about a 1" wide strip, but it does the job.

Little progress today. I installed the control arms, brakes, and struts. Not exciting but I wanted to test fire the engine on its wheels instead of on jack stands, due to vibration. Also, new CCV breather hose, new N75 valve and sorted most of the vacuum hoses. I didn't have enough fuel hose to rig up a temporary fuel tank, so I didn't get to start it today. It does turn over though, which is a good sign.

As it sits today:

Quick question, no picture though. What are my options for upper radiator hose? I would like to use the Corrado hose, but the coolant overflow tank line is molded into it, right near the radiator neck. This is fine with me since it is towards the high-point of the system, and should help prevent an air pocket. If i use this hose, I need to get a different flange for the engine side, since the tdi flange has the overflow line in it like this image from "myturbodiesel". Is there a flange will fit that doesn't have the overflow return in it?

 

[G60ING]

I chose to use the Corrado G60 hose and T its hose into the one from the front flange. The Passat TDI hose should work from what I've researched. Evenetually when refresh my cooling system I'll buy both an upper and lower Passat TDi radiator hose.

here is the 1st version of what I did:

the 2nd version:

 

[JFettig]

Yes, the one I have in my Passat doesn't have it in it.
flange(028121132) and o-ring (N90316802)
http://stuff.jfettigmachines.com/tdi/engine cavity/tn_IMG_2217.jpg

I believe I ordered these parts from worldimpex.

 

[greasyrides]

Thanks for looking up the info on the flange. Impex is not far from my house, but at $27 for a plastic flange, I'm just gonna go with Frank's idea and Tee the two overflow lines into the coolant bottle.

 

[greasyrides]

Cluster

Short Update: I hooked up the cooling system and a temporary fuel tank, bled the fuel lines and she fired right up! I didn't snap a video, but I will next time I work on the car.
I finished up my brake lines, so now every line in the car is new, and the rear proportioning valve functions now instead of being a big block of rust. Every line from the prop valve back fought me the entire way...many were rusted badly and broke right in my hands. It's reassuring knowing that when I slam the brakes now I won't pop a line. All hard lines are "EZ-Bend copper" with braided stainless flex lines.

Question(s): My cluster powers up but doesn't work. I checked the grounds in these locations: Big ground on bell housing to battery, body stud under battery, 3 small wires near head (under large main engine harness plug). These all look good.
I tried my spare GLX VR6 cluster and that also powers but none of the gauges work. I only have a working LCD, no warning lights, no gauges.
There are several individual wires in the cluster wiring harness which are not plugged in: T28/14 (trunk unlocked), T28/22 and T28/24 (turn signals), and T28/28 (gear selector). I don't think any of these would cause my symptoms.

Any advice on where to look next? Also, is there a writeup on bench testing a cluster to see if perhaps I have 2 bad clusters (doubt it)?
Thanks,
-Mike

 

[G60ING]

Odds are the clusters are fine and you have a bad ground or power feed. Start looking at the wiring diagram and making certain with a muilti-meter that the main circuit connections are made properly.

 

[greasyrides]

Looked over the wiring diagrams a bit (I'm not great at reading them, but getting better)...I may have found my issue, but I won't get to verify this until later this week when I work on the car again.

According to A2 resource my Fusebox D/11 and E/2 should be connected for Start/Run Power to the instrument cluster. E/2 connects to U2/1 inside fusebox. Since my car is a 1990 G60, this connection would not be present, correct? So I need to add a jumper between these two and my cluster should see power, does this sound right? I can't find a clear picture of either of my fuse boxes to verify if I have this connection or not.

Would I still get power to the odometer/clock if this D/11 to E/2 connection was not present? I think I would thru U2/11 (gauge cluster clock/MFA). These went out when I pulled fuse 21.

I hate tracking down miscellaneous connectors/continuity so fingers crossed that this is my issue!

 

[G60ING]

You will need to add the TV junction blocks to the corrado fuse box like the donor car had.

here is a thread where I tied to help somebody by posting pictures for some of what is required. You will need a junction block for the black wires, grey with white, and blue with white wires.

 

[Crazy Conversions]

looking good man, i might do this with my corrado and have a nice little tdi family!

 

[G60ING]

You will need to add the TV junction blocks to the corrado fuse box like the donor car had.

here is a thread where I tied to help somebody by posting pictures for some of what is required. You will need a junction block for the black wires, grey with white, and blue with white wires.

sorry I forgot to post the link
http://forums.tdiclub.com/showthread.php?t=283664

 

[greasyrides]

Thanks for the link. I did a fairly poor job labeling those TV plugs when I removed everything from the donor, so I ended up soldering a jumper from D11 to E2 and now I have working gauges! I then temporarily hooked up the OBD port to see if my scangauge would "see" the computer.

Quick YouTube video of my gauges lit up: http://www.youtube.com/watch?v=xV42pSwmiKg

I didn't have a helper so I didn't get to bleed the brakes and a few other things before I can test drive it, so I started re-assembling the interior and installing euro-belts.

I'm headed to the junk yard to find some small parts I need. I'm gonna look out for AC components. Is there any R134 system where the Condenser will clear the Corrado's upper radiator support (aside from a 93+ SLC)? I thought I could get lucky and use all of the passats components without custom lines, but the condenser to compressor line goes over top of the radiator and hits on the rad support (driver side). I would hate to hack up the rad support just to clear an AC line.

 

[G60ING]

Just use an R12 a/c condensor. I did and my a/c works great.

 

[greasyrides]

Thanks, looks like I'll at least need a custom line from the condenser to compressor. I grabbed a MKIII line for the evap to compressor...that fits a lot nicer than the B4 line I had mocked up.

Which Accumulator/Receiver Drier should I use if I'm going to use the 1990 condenser? I believe the driers are not interchangeable between R12 and R134a, but I may be wrong. Does the 93 drier fit on the 90 condenser?

Lastly, pressure switch. Just use the G60 stuff since I'm using the G60 fan harness, right?
Thanks!

 

[greasyrides]

No Start?

Last week the car would start beautifully (once I figured out my cluster power). I tried starting it this weekend and it cranks but doesn't fire. Good battery and no air in the fuel lines, so I assume it is Relay 109 as now I have no glow plug light and no CEL test light. Do these relays just go bad like this with no warning? I ordered two, so I will have a spare, but I was kinda bummed that it wouldn't start for me this weekend

It is rapidly approaching being a drivable car...I'm waiting on the Relay 109 and some CV joint gaskets so I can install the axles, then it will be time for a test drive!

Since I was waiting on parts, I spend time this weekend on the interior. I have most of the interior refurbished and installed in the car, just need the front seats and door cards. I went with black carpet, black euro-belts, black trim, black suede headliner (nice), and tan seats and door cards. I love the black and tan look. I spent about 10 hours on the interior, between swapping all the trim, installing the dash, seat-belts, and cleaning the leather and carpet.

 

[GTiTDi]

Nice interior! suede headliner is where its at, that's what I used in my GTI

 

[greasyrides]

Vacuum Diagram

Since I have blocked off the exhaust gas recirculation flow, the EGR valve is now useless. Can I eliminate the N18 valve and it's associated vacuum hoses, or will this cause a CEL and other adverse effects? I have a "Speedtuning" chip, which came with the car so I'm thinking that the EGR function is already disabled (and I plan on getting rocket chipped once I rack up some miles and install injectors).

Here is my proposed vacuum diagram. Does anyone see any issues?

 

[slow-moe]

No issues and no cel. Only a fault code, that you can get rid off if you put a resistor in place of N18.
Further you need to plug the nipples from airbox and vacuum distributor, fuel caps from return line of #1 injector works fine.

 

[greasyrides]

N18 Resistor

Any idea what resistance I need to emulate the N18 signal? I thought this was a dynamic signal so a single resistance would also throw a code. I searched for an answer but came up with very little.

I put in a new Relay 109 and installed the axles and took her for a short test drive (no tags on a private road ). Sounded and felt good for an engine that was sitting for over a year. Still tons to do, but it was rewarding to get in a short drive after all that work.

I only hit 12psi boost and I pulled 3 codes (one of which was for the N18) so I think the PO may have lied about it having been chipped by Speedtuning USA...or their chips suck.

These were my codes pulled from Scangauge:
P1447- catalyst temp. circ open/short to B+
P1401- EGR Vacuum Regulator Solenoid Valve -N18- Short Circuit to Ground (GND)
P1144- Mass Air Flow (MAF) Sensor -G70- Open Circuit/Short Circuit to Ground (GND)

The first two make sense...I did not have the catalyst temp sensor plugged in, and the N18 is not installed. MAF code I'm hoping goes away. I'll double check my connection and clear the codes and see if that does it.

 

[Houpty GT]

I was talking to Jeff from Rocket Chip about removing my N18 EGR control valve and he said to use a resistor with a higher wattage rating like the white stone resistors. He could not remember the resistance but he said you could ohm out the valve to find your value. He said the valve won't run with the EGR delete tune but the computer will still check to see if the valve is there.

 

[greasyrides]

I may just install the N18 valve, but not hook up the vacuum hoses and see if the code comes back.

For reference I found a tech writeup for the ALH N18 that states that the resistance should be between 14 and 20 ohms. 20 ohms being a warm engine. I did a quick search of resistors and a 15 ohm 10w resistor would be about perfect (P = V^2/R).