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yup - just peel .035" off one face and put that face toward the mounting plate.

The lower idler appears to be non grooved. Is that a Dayco as well?

no. that is a custom pulley.

I don't dare to stick the stethoscope on that one! <img src="/forum/images/smilies/968/biggrin.png" class="smilie" alt="" /> Lots of "spinning bits" in there, not the least of which is the alternator vanes! <img src="/forum/images/smilies/968/ph34r.png" class="smilie" alt="" />

Any way to replace that one if it's the problem? Granted, I don't *know* it's the problem, but I'm figuring I'd better have my ducks in a row / options lined up.

OK, I did some more testing tonight. First of all, I verified that the Hall Sender is +5V with a voltmeter. (Doesn't tell me if it's a waveform of a certain shape, but it does show it's working.) I still need to unplug it and test the car without it as flash suggested.



Next test - flash suggested I take off the belt guard and see if it still makes the "ting" noise, so I took off the belt guard and was surprised to find some wear on the underside, indicating that perhaps my belt is too loose? The paint is worn off on the lowest edge, and it has been rubbed by some of the other ribs.







The belt guard was at a slight angle as indicated in the instructions, and the wear is heavier on one side, also showing it's at an angle. It was also at the top of the screw holes as required. I also found a little bit of wear on the "S" pipe which was a surprise as I had more than the 2mm of clearance there, but maybe the belt was that loose and "slapping". That's one spot I keep a close eye on because of the tight clearance, (and the alternator vanes near the upper radiator pipe is another spot I am just generally nervous about). The angle of the photo shows the clearance, but not the wear - there's a little rice-grain sized part where the powder coat has been rubbed.







Just for grins, I put the Krikit on the top run of the belt and measured the tension. 30 lbs. on the dot.







So, (and this is important for the next paragraph), because of the wear, I loosened the silicone bell and pushed the "S" hose a little further onto the throttle body and away from the belt. I verified it wasn't interfering with the swing of the throttle plate by working the throttle back and forth by hand. Then I started the car and it ran fine for several minutes. There was no "ting" sound.



After a few minutes, the idle dropped very low and I thought the car was going to stall out. It has never done that before when just sitting idling. It recovered after about 5 seconds, but the check engine light had come on. I did a "blink test" and got a 1-2-1-6 (Throttle Potentiometer). This is new - never seen it before - and I wonder if pushing the "S" pipe further onto the throttle body could interfere with it in some way? I restarted the car and it smelled very, very rich. I turned off the car and verified the "S" pipe doesn't interfere with the throttle, at least not visually, although it is close to touching the throttle's return coil spring.



I shut everything down and came inside to post this and pack for Vegas. I welcome your constructive comments. <img src="/forum/images/smilies/968/wink.png" class="smilie" alt="" />

moving in inward won't mess with the throttle pot. are you sure the connector is fully seated?



make a small notch in the adaptor hose to clear the spring if you need to.



make sure your clamps are tight with no gaps. use a nutdriver not a screwdriver. it's pretty easy to get a leak at the corner of the charge pipe if that clamp is sitting just right. that will cause things to get wonky.

OK, I'll double-check all the fittings, including the electrical connector. I'll give it a squirt of electronics cleaner for good measure.



The little silicone bell hose is already notched, but I'll double-check and notch it some more if it calls for it. It's possible I loosened the hose clamp on the throttle body and didn't re-tighten it. <img src="/forum/images/smilies/968/blink.png" class="smilie" alt="" />

[quote name='tamathumper' timestamp='1368138576' post='142561']

OK, I did some more testing tonight. First of all, I verified that the Hall Sender is +5V with a voltmeter. (Doesn't tell me if it's a waveform of a certain shape, but it does show it's working.) I still need to unplug it and test the car without it as flash suggested.



[/quote]



I don't think the DME cares about the exact wave form. I'm pretty sure that the hall sensor will give a step rise in voltage as well as a drop, but it is not a clean square wave. If memory serves, it is just this step rise that the DME is looking for, and which it triggers off of.



I assume from your comment, that you are getting a consistent output of the hall sensor, unlike the tach test, where it seemed intermittant.

Yes, I'm getting a constant +5V off the Hall Sender (cam position sensor) with the ignition ON, and also with the car running. The needle on my multi-tester does not move at all. My only test of the crank position sensor was with the tachometer, and that was all over the place.

With what you've said, I suspect the Hall sensor is OK, but as mentioned, the DME works off of seeing the sudden change from 0 to approximately 5 volts. It triggers off that step/spike in voltage.



With the car running I can see that you would get a consistent 5 volts, as the response of the needle probably can't follow the rapid change in voltage. What happens if you just jog the starter. Do you see the voltage change between 0 and approximately 5 volts. And, do you have the multimeter on a DC setting. If you have it on AC, it will only give you the peak reading of the pulse wave so you won't see the voltage change. You want to be sure to see it change from 0 to 5.

I have it set on DC, 10V, so the needle moves halfway across the sweep range (to 5V). Testing the two outer pins, it is on 5V both with the ignition just set to "ON" (or "RUN"?), and with the car running. I've not seen it go to 0 except with the ignition set to "OFF". (Apologies, I'm using caps for emphasis, not to shout).



The wiring diagram for the Hall Sender is a bit confusing - one of the wires is apparently connected to the shield of the cable itself, and on the far end it goes off at a 90-degree angle to what looks like a little "B"? That pin is, I think, in the center of the connector, and is very well shielded, unlike the other two which are bare metal.



I'm taking my reading from the outer two pins, but that could very well be incorrect.

It's not a whistle. Clearly your gas tanking is merely begging for more gas! I have a whistle too and have had people tell me they have heard it and knew a supercharger was making it. Must be pretty knowledgeable folks.

The hall sensor should have three wires leading to it.



-ground

-power

-sensor signal (which should vary between 0 and 5 volts (assuming it is powered by 5 volts)depending weather there is metal in the gap of the sensor (5 volts) or air in the gap of the sensor (0 volts).



Tama, so here is another test that I though of which should work for you. With it you don't have to worry about the response abilities of the multimeter, nor if there is metal in the gap of the hall sensor. Pull the coil wire so the engine can't start. Identify which wire is ground by checking continuity to the chassis, or a good ground point on the engine. Turn the ignition on. You should see 5 volts between the ground and the power lead (or 12 volts if the sensor is 12 volt powered), but here is the catch that may have been the issue in your test with the engine not running. If there is metal in the gap of the sensor, even if the engine isn't rotating, it will read 5 volts. So, here's the alternative way to test; put a socket in the crankshaft bolt, and slowly turn over the engine. On the power line the voltage will not vary (either 5 or 12 volts depending on the power source). On the sensor signal wire, the voltage should vary between 0 volts when no metal is in the hall sensor gap, and 5 volts when there is metal in the hall sensor gap from the 4 lobed wheel that passes through the gap in the sensor.

Good thought. I'm at the gate waiting for my flight to Vegas and I've got three days of bombing a Boxster through the Grand, Bryce and Zion canyons so I'll have to do it when I get back! <img src="/forum/images/smilies/968/wink.png" class="smilie" alt="" />

If I get a chance, since I've really haven't worked with Hall sensors other than for ABS systems, I'll try the test on my car. It's laid up right now anyway waiting for a new balance belt (the suddden super whine that caused me to abort after 4 runs at last weeks autox was a bolt that had wedged itself between the corner of the balance belt and the bottom belt cover; put a nice 45 degree chamfer on the edge of the belt). Be nice to identify the wire color for each of the three inputs for future ref.



Have fun on your drive at 4 corners. Its on our go to list.

From the little stubs I had exposed, the front wire was red, the center wire was a big black one, and the rear wire was grey.

Much of the noise heard through the stethoscope is gone now that the belt guard has been removed. I will attempt to tighten it up to the correct tension and then take another reading with the Krikit.

I tensioned the belt to 70 lbs. (measured with Krikit on the lower span, just above the tensioner). Upon test drive, noise is now gone, only the "whistle" remains. <img src="/forum/images/smilies/968/smile.png" class="smilie" alt="" />



Once warmed up, this car goes like STINK! (which is good).

After a couple thousand miles, I re-checked the belt tension again yesterday. It is down from 70 to 50 pounds as measured with the Krikit and the first groove of wear has begun to show again on the belt guard.



I know there isn't a spec for the belt tension, but can anyone pop a Krikit (or some other method) on yours and tell me how tight your SC belt is? I might be overly cautious and keeping it too loose?

increase the angle of the tabs on the belt guard, drill out the holes a bit bigger, and pull it upward as much as you can.