3B swapped US model 90 running issues

[Racerguy381]

It's been running for over a year now but still has issues. Intermittent boost pressure, oil light still flashes, anitlock comes on and off, idle changes and sometimes dies after acceleration. Switching it to VEMS this winter and hopefully it solves a majority of the issues.


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[WidowmakerS2]

Following this thread.

I've had the same problems with my conversion (7A-3b).

[Racerguy381]

Ok I have sorted out the overheating issue and the turn signal problem. Turned out that the intermittent wiper relay is where the thermal switch gets its power from. The fuse to the wiper relay was blown... I am still chasing the oil light though. I checked all the wiring at the cluster and it is all pinned correct. I also checked the signal from each sending unit to the cluster which all checked out as well as the ground circuit. Yet the light still flashes constantly... I am leaning towards a bad auto check computer but its the same one that worked perfectly fine in my car before I tore it apart. Thoughts anyone?

[Racerguy381]

3B swapped US model 90 running issues

Well I've ran into another issue... I had the car drivable and was able to take a few short trips close to home with it without any issues. So I decided to take it for a longer trip yesterday. I got about 10 miles from my house and the temp gauge started to climb. The car ended up starting to overheat so I got off the freeway. I determined that the cooling fan is no longer coming on. All three terminals on the thermal switch plug are grounded now. As well as I'm not getting any power at the fuse. But I do have power at the relay but no ground. It seems the car is also running in limp mode. It will not rev up at an idle if you barely touch the throttle. If you give it about half throttle it will rev up. From what I can determine I have a ground issue going on either in the fuse box or in the harness. Anyone else have this issue before and know where I should start looking? Oh and the third thing my turn signals are not working. But they do work on hazard.... [emoji52]

[UrS4boy]

7A, 3B and ABY Oil Pressure Senders and Switches

Here are some PNs. In both cases (7A and 3B/ABY) the separate 1 pin oil pressure switches are the same, i.e. 056919081E. Also, the oil pressure gauge sender with built in oil pressure sender is the same PN, i.e. 035919561.

7A:



3B and ABY:

[UrS4boy]

AAN Oil Pressure Sender, Switches, Wiring and Check Valves

Not sure if this will help you or not but it is probably worth at least reading through it for ideas:

AAN Oil Pressure Sender, Switches, Wiring and Check Valves:
http://forums.quattroworld.com/s4s6/msgs/96161.phtml

[Racerguy381]

OK so I'm really scratching my head on this one now. I've checked the pan out on the wiring diagram and the plugs which is all correct. Yet I'm still getting a flashing oil warning light on the auto check before and after I start the car up. Both temperature and oil pressure gauges work fine as well as the sending units. Any thoughts what could be causing this? Is there another system tied into that warning light?

[Racerguy381]

Strange I looked on there for these and couldn't find them except the ones in Norwegian. I really appreciate the help hopefully I can determine what wire is either missed pinned or if I have a bad sensor. I have oil temperature and oil pressure on my auxiliary gauges though so I'm assuming that the sensor is fine.

[UrS4boy]

But better, if you go to S2Central.net and drill down to 3B S2 wiring diagrams, you will get to this: http://www.s2central.net/S2_Schematics/D/D17.PDF

When you go to pg. 3/7 of the pdf you will find the 3B info you need on Tracks 22 and 23 for the F1 and F22 oil pressure senders as they go into the J189 AutoCheck module.

[Racerguy381]

I have the wiring diagrams for the 200 but the diagrams I have for the 90 do not include the auto check portions.

[UrS4boy]

So you do have this?

http://www.isham-research.co.uk/quat...tem_Mj1997.pdf

But you don't have this: http://12v.org/urs/audi_c4_wiring_diagram.pdf ?

If you don't download and save and then go to Figure 40 on pg. 51/113, tracks 118 and 120 should be what you need. Or NOT (they are AAN-based, not 3B).

[Racerguy381]

Ok so I could use a little more of all your expertise on this. I'm down to the last few little things I need to sort out and one of them is the oil light flashing on the auto check computer. I'm pretty sure I have the pit out correct but not 100% positive since I do not have an English version of the wiring diagram for it. Blue with a black tracer is the wire I believe that needs to be in pin 24 of the yellow 26 pin connector. Or does it need to be in pin 19 of the white 26 pin connector. Either way I've tried it in both in the light still flashes in the auto check computer. Any ideas what else it could be? Or does anyone have a English pin out for the auto check?

[UrS4boy]

Ok, what strenght should be the spring then ?

Force = Pressure x Area (e.g. lbs/sq in x sq in OR N/m^2 x m^2)

[Racerguy381]

Great info guys! Thank you so much for your help!

[etsola]

Ok, what strenght should be the spring then ?