obd2 tb on obd1 managment

**mk3pete** · 04-01-2010, 04:35 PM

hey all im looking at getting this done as i bought a tb from ebay thinking its a obd1 but its not

few questions not sure on all the abbreviations mean?
ISV?
EGR?
integrated TPS?
and does anyone have these parts that are required?
obd2 upper intake manifold
OBD2 ABA harness
also would like a wiring diagram too
and finally will the obd2 upper mani adapt to the obd1 lower mani. reason i ask is i already have a spare obd1 lower mani i bought off golf loon.

anyways it is possible. this is the thread!!
http://forums.vwvortex.com/zerothread?id=4246448

You can absolutely swap them out. I ran both an obd1 and an obd2 throttle body on my standalone car and both throttle bodies provide the same input/output (+12v, GND, 0-5V signal). The obd2 connector just has more pins so you have to get a wiring diagram to find which ones need to go where. I believe Paul (need_a_vr6) has an obd2 throttle body on his obd1 motor... I may just be remembering that wrong though.
Benefits:
-68mm butterfly vs. 62mm (20% increasing in area)
-It already has the crazy ramps removed so you don't really need to port it

Disadvantages:
-Will need to swap to obd2 upper intake manifold or use an adapter plate
-Integrated TPS

I run an OBD2 tb on my OBD1 managment, but I also run an OBD2 VGi manifold. They left the ISV port on the manifold so all I had to do was wire in the OBD2 TB's tps into my wiring. I cut a pigtail from an OBD2 ABA harness I had around and just spliced it in. I didn't have luck trying to use the OBD2 tb's idle motor with the OBD1's controls.
For a stock OBD2 manifold you'd have to add the port for the ISV to make it all work, as well as delete your EGR system or add the port for that as well.

**peedman** · 04-01-2010, 05:27 PM

pete,

isv = idle stabilisation valve
egr = exhaust gas recirc
tps = throttle position sensor

what did u want to do exactly with these parts?? did u just want to go to the bigger throttle body???

**VOLKSMAN** · 04-01-2010, 06:10 PM

if its such a mission. im pretty sure you can go to a euro wrecker and swop yours for an 0bd1 tb.

i guess they wouldnt mind since the 0bd1 is less intelligent and depends more on mechanical than electronic controls.

or you may have to pay a couple of dollars extra (worst case scenario)

**mk3pete** · 04-01-2010, 06:25 PM

iv got the obd1 tb already
my intension was to upgrade to a bigger tb, so i bought a 2.9 tb from ebay thinking it was obd1, it was infact obd2
its been ported and polished

**mk3pete** · 04-01-2010, 07:52 PM

ok i just read my own post again now knowing what each abbreviation stands for

cheers pedro

anyways it seems fairly strait forward
first source obd2 upper mani and wiring loom
find out where to splice in the wires
add in a port for the ISV on the mani
and away she goes, i think

**VOLKSMAN** · 04-01-2010, 08:09 PM

that makes sense now, but i have read on vortex that obd1 throttle bodies have larger bore than obd2 (on the 2.8 that is) .

**mk3pete** · 04-01-2010, 08:31 PM

not sure on that one matey
but i just measured my new tb and its 68 mm roughly
with that info im assuming the obd1 tb is 62 mm

**mk3pete** · 05-01-2010, 11:14 AM

quick bump

does anyone have these parts that are required?
obd2 upper intake manifold
OBD2 ABA harness
also would like a wiring diagram too
and finally will the obd2 upper mani adapt to the obd1 lower mani. reason i ask is i already have a spare obd1 lower mani i bought off golf loon.