Varioram update... No signal from DME

Moses · 06-16-2003, 07:25 AM

Well, I now have 2 DME's. One from a non V-ram '95 and a second from a '97 Vram. Using a voltmeter with long leads and driving with the motor under load, there is no signal from either DME to the V-ram.

I'm guessing my brilliant ex-mechanic wired this wrong. Anyone have any idea how the V-ram is supposed to be hooked up to the harness?

widebody911 · widebody911's Garage

Have you checked that the DME is turning on pin n? Do you have a pinout diagram for your DME?

Here's the pinout for mine. There's a bunch of 'not used' pins, so those are either top-secret MS-like function calls, or one or more of them would run the V-Ram.

Moses · 06-16-2003, 07:38 AM

Thanks Thom,

I'll look for a pin-out diagram. Any idea where to look?

widebody911 · widebody911's Garage

Quote:

Originally posted by Moses
Thanks Thom,

I'll look for a pin-out diagram. Any idea where to look?

Find a friend with the Mitchell or Alldata manuals, or someone with the Bosch DME book. I did a search on google and came up dry. Adrean Streather has the Bosch DME manuals, maybe if you ask reaaaallly nicely. He bailed my a$$ out when I was doing the smog dance on my car.

911nut · 911nut's Garage

Moses, apparantly replacing your 3.0 motor was bad ju-ju

Embs · Embs's Garage

Moses, I don't know if this helps but it is a 993:

Embs · Embs's Garage

Don't feel bad Moses, my Varioram system has never worked either!

1fastredsc · 06-17-2003, 05:03 AM

Mitchell has very good wiring diagrams, a little less confusing than factory manuals i think.

widebody911 · widebody911's Garage

I find it interesting that the pinouts are different, even though the connectors are the same. So much for plug-n-play with that 993TT engine...

thabaer · thabaer's Garage

The resonance flap on both pinouts looks like the control, but do you know what kind of signal it delivers ? You may need to be checking a duty cycle (PWM) instead of steady voltage.

pbs911 · pbs911's Garage

Moses, didn't Timmins have the motor in one of his cars and running?

Moses · 06-17-2003, 08:09 AM

This brings up a second question. There is no data port connected to the DME. How difficult would it be to connect one? It would sure make diagnostics easier. As it is now, I have to hook up a voltmeter and go for a high RPM drive to check the signal. Anyone have a data port on a 3.6 transplant?

Moses · 08:18 AM

Quote:

Originally posted by pbs911
Moses, didn't Timmins have the motor in one of his cars and running?

Yes. So did I. But I never had a functional varioram.

My ex-mechanic killed the DME that came with the car. Timmins sent a '95 DME replacement that he assured me would operate the Varioram. It did not. So I bought a second DME from Timmins (a '96 V-ram DME) This one also does not trigger the Varioram. Most likely conclusion; my ex-mechanic may have wired the harness incorrectly. (He may be an ex-Jaguar electrician double agent still bitter about WWII. Or he may simply be an idiot. He had my car and my money for 6 months and never got it right.)

Embs · Embs's Garage

Moses,

Call Steve Weiner or try and stir him up over on rennlist. He will have some good info. He has (correctly) done more of these than anyone else.

ischmitz · ischmitz's Garage

Moses,

pin 1 is the correct pin on a 993 VarioRam. It should cycle the resonance flap when you turn on the ignition and start the motor. No need to run the motor under load and >60% throttle.

You should be able to hook up a simple volt meter to the wire connector that runs to the vacuum solenoid valve and be able to watch a signal. No duty cycle - just either nothing or 12V. If the signal is there but your flap does not move you have a vaccum line problem.

Adding a diagnostics port should be not all that complicated. All you need is the round multi-pole (17?, don't have my shop manual open) connector and some wiring from under the drivers seat to the connector. As far as I remember you need to wire ground, +12V, K-lead, L-lead and that's it. I was thinking of adding one myself but the testers (Bosch hammer) are so expensive that I don't see myself ever buying one just to play with it.

Ingo

Moses · 06-18-2003, 08:31 AM

Thanks Ingo. So if I get it hooked up correctly I should be able to watch the valves actuate on startup, right. I don't suppose there would be a Euro/US difference in this startup cycle. I have a friend here at work with a 993 V-ram. I think I'll ask him to start his car for me so I'll know what I'm looking for.

widebody911 · widebody911's Garage

On my car, the resonance flap 'flips' when I turn the key on - without starting the engine. My mechanic told me that it's part of a self-test the DME does. For the 'normal' 3.6 engines, this comes on @ 5100RPM. If it doesn't come on when you turn the key, it will not come on @ 5100. I've only seen one other 3.6L conversion in person which this was hooked up correctly. FWIW, having the resonance flap hooked up correctly maded 12hp on the dyno.

Moses · 06-18-2003, 09:37 AM

Quote:

Originally posted by widebody911
... FWIW, having the resonance flap hooked up correctly maded 12hp on the dyno.

I'm a little compulsive about some things. If I don't hook up the Varioram, then that big silver intake system on my motor is merely decorative. And 12 HP is, after all, 12 HP.

k9handler · 06-18-2003, 09:40 AM

quote

I've only seen one other 3.6L conversion in person which this was hooked up correctly.

I am not sure of all this lingo...but I have complete faith that Harald and Ingo hooked mine up correctly.

widebody911 · widebody911's Garage

It made 12hp on my non V-Ram engine. It would make more on yours.

Quote:

Originally posted by Moses
I'm a little compulsive about some things. If I don't hook up the Varioram, then that big silver intake system on my motor is merely decorative. And 12 HP is, after all, 12 HP.