The Project Pad

Hmm Derek, that is an interesting thought. Just to note, my 20v had the sensor in the exact same spot, and it ran like a top for 20k miles.. But just to make sure that it wasnt a problem, I moved the sensor, which is now on the bottom of the motor next to the oil pan, and there isnt anything close to it, just aluminum..

The sensor is being held by that black bolt which runs through the billit piece and pinches the two sides together to secure the VR sensor. The bolt isnt stainless, but the stock sensors in their stock location have a bolt to secure them, and it isnt stainless. I will probably get a stainless one though just to rule that out.

my question is why in the world I only get WG numbers in the single digits and the super high RPM...

Give me a welder and something to fab, and I am good to go... Tell me to wire something, and I always screw something up.

Hank

What is the sensor gap?

well I have tried from .02 all the way up to .1" but curently it is at about .05..

Ok, another shot in teh dark....looks like the pulley's been painted/PC'd - are the teeth painted too? Hard to tell but in that 2nd PS picture they look blac(painted) - scribe the paint off if that's teh case??

Does the desired 8-20 teeth BTDC matter? Is this a crank pulley you added the magnetic wheel to or did you buy the pulley from 034?

8-20BTDC shouldn't matter - it should still read 59 teeth.

:stupid:
The ECU still ought to pick up the 59 pulses in between the flat spot. The pulley we are using is a home machined and welded MC unit using an 034 toothed wheel. We have metered the VR's swiping them with a ferrous material and have seen up to .2V. We hav used 3 different sensors and like Hank said earlier, we used me flying leads off of my IIc and ran the prewired shielded twisted pair on the outside of the car to the VR and still couldn't pick up anything resembling a decent signal. As for paint Peter, the wheel and pulley assembly was bead blasted and painted before putting it on the lathe to true up the teeth, so the ends of the teeth aren't painted even though I don't think that it would matter much. At this point though, any in the dark suggestions are welcome. Thanks

Can you turn it by hand and notice any fluctuations between the teeth and the sensor? Just a thought.

Haven't tried it, but it sounds like something to try and see if the VR's magnetic lines of flux are coupling with the teeth on the wheel. We ought to be able to pick that up with a meter. We did try to pick up the signal with the meter at the end of the VR cable while cranking with the starter, but the digital meter isn't fast enough to read anything meaningful. I sometimes wish I still had an old Simpson 260 analog meter (nothing like dating myself). At least when the needle deflected, you knew it was because of a signal and you weren't waiting to get through an A/D converter and processor. Oh well

Do the wires go directly from the ECU to a connector that connects to the VR or are they spliced to connector wires that then go to the sensor?

We left the stock connector on the VR and bought pins to make up a female connector on the end of the twisted/shielded pair coming directly from the ECU. The same cable that was used when it was a 20v EFIed car. the only difference is that the wheel that we used before was welded on the outside of the damper/pulley and wasn't the best job, so we instead machined the pulley to accept the wheel on the back.

<whistling as he enters the room>

Doatie doat dat deeeee.......

Dont mind me..

So how is everybody!! 'Bout them promises!!

Hank

I take it the VR sensor situation hasn't changed much. You should read my project thread just so you can feel a little better. I had many a problem that I frequently encountered before finally enjoying the car.

Hank, what's the runout on the wheel look like? On one hand, for whatever reason, my first wheel worked like ass, but my second one, which has quite a bit of runout, works fine.

It sounds like you're getting MANY false trips. Maybe try another sensor/rotating that sensor 90*? Also, I'd try repinning the connector, sounds like the ground/output could be reversed.

Sam

Ok so that was a little misleading.. SO a weekend after chasing my tail, we did a few things different to see what was going on.. I rewired everything a couple of times, trying to rule out interference.. and took the wheel off, to see if it was true.. its within .005 thousanths.. that isnt hte problem.. I redid the bracket, just to get it away from the Alt.. It is exactly 19 teeth away from the gap, which i dont like a bunch, but the manual does say 10-20. I took another pulley we have been working on, and made a variable speed motor jig with it to check it, and see if we could get it to read.. We could. Quite well actually.. however wiht out painted one, with much tighter tolerence, it wasnt going.. So I was pissed.. I filed off the paint, and that seemed to help.. VR sensors are just sucky at low speeds.. It is hard to get them to be steady at under 200 rpms.. at 500, both the pulleys resulted in a solid 59, but under 200 it was tough.. I estimate that the motor cranks at 250 or so.. Anyways, so the thinking I had is just that the motor needs to be gerenally in the right spot, and then just get lucky on a spark to get the thing to come around.. So we put everything back together, and tried again.. this is what we came up with..

http://www.youtube.com/watch?v=xY1HYUffqTY

Ok, so it starts and idles quite well, and is on the right track.. I need to trim out the timing, and fix an anoying trigger wheel that is so slightly rubbing on the cover, but then it is just puting things back together.. and dipping!!!!

Enjoy!! Thanks for the help guys in the trouble shoots, I may credit the paint comment with the problem, although it seems hard to believe!! But thanks.. Huge thanks to my Dad too, he was a trooper in helping me out, and keeping me going on the right direction!! oh and he bought me a case of Dr. Pepper when the going was getting tough, and even came out in his underware at 3:00 am when the car fired up!!! I dont know why he woke up!! his room is just on the other side of the wall!! yeah, I am a jerk!!

!! Oh yeah!! This is only the second time that i have seen a 20vt in real life, and the first time I have heard one in real life!!!! LOL, no audis in Vegas!!! The car sounds swweeeeeett

Hank

Hank

Just drove through vegas twice this weekend... if I had more time would have loved to have seen this monster... I'm sure there will be time for that in the future... Congrats on getting it running... now you get to enjoy the fruits of your labors...

This is only the second time that i have seen a 20vt in real life, and the first time I have heard one in real life!!!!

He's lying......I let him take the TT 20v on a date just Friday night. Wrong kind of 20v you say!!

quattro87 wrote:

This is only the second time that i have seen a 20vt in real life, and the first time I have heard one in real life!!!!

He's lying......I let him take the TT 20v on a date just Friday night. Wrong kind of 20v you say!!

Wait a minute. You mean he went on a date instead of working on the car?? Slacker!! :wink:

Good to hear it running. Although I could have gone without the "Dad in the underwear" bit. Bad, bad images.

:woowoo: :woowoo:

Hank,

Great to see the progress. You're almost there, buddy! Keep it up. :woowoo:

i'm waiting for "hank does donuts and catches his car on fire part duex" on youtube

derracuda wrote:i'm waiting for "hank does donuts and catches his car on fire part duex" on youtube

quick, somebody find that link!

Congratulations man.

I'm sure it's going to be worth it.

This thread really motivates me to finish my urq.

great work

Cheers,

Craig Cook.

http://mswanson.com/~jgreen/hank.mpg

One of our favorites at home!!

one of these years we'll have to get a couple MG'ers out there doing donuts simultaniously... maybe four of us perhaps... that seems to be an appropriate number