Ed's 1991 CQ: Progress!

[Hank]

that sucks

[Mcstiff]

Yeah, wish I'd of done another rotation by hand!

Oh well, I'll probably just get the oil filter and turbo oil drain line out of the way and hopefully I can get a drill/grinder/rotary tool in there to clean things up. It occurs to me that I don't have to use the stock location but I like the idea of having the stock hole.

[Mcstiff]

Updated plan, drill 7/32 hole, insert 3/16 square key, weld.

[easterneurocoupe]

Same size and tap it in w hammer, thats all i did and its held up a long time

[Mcstiff]

The 7/32" hole is just narrower than the corners of the 3/16" square (1/4" diagonal). It will be a press fit but I'll tack the end to be safe.

[bdcoombs]

whenever you build things the second one built is always better the first.. so i see it as a good thing :thumbup:

[Mcstiff]

Drilling through welds sucks!

Starting to get tempted to move the pin but then I need to figure out where it is.

[Mcstiff]

I've barely made a dent with a new cobalt bit :banghead: So 3 teeth is 8 degrees, I can't think of a reason not to move the pin (slight imbalance).

[TheArchitect]

I can't think of a reason not to move the pin (slight imbalance).

As long as the tooth is between two flywheel teeth just like the original ref pin was, you can put it anywhere (ignoring ever using the stock ECU again).

[Mcstiff]

The only way it is getting a stock ECU is with a new harness

Since I'm getting nowhere drilling (new bit still in good shape but still not making progress) I'm just going to tack on a square stock pin at the site of the old one.

[Mcstiff]

:banghead: Still "no" signal. Can anyone measure a 3b/AAN pin? I went 3/16" because 1/4" hits the sensor. I see a wave on my oscilloscope but I'm not to reading it so I need to figure out the intensity/settings.

[Mcstiff]

Ignore the white lines on the left...



I need to mess with the resolution some (shorter horizontal scale).

[Mcstiff]

Better scale:

[Dave]

your pictures don't work.

[Marc]

the trigger voltage looks good, but the polarity looks backwards. the sine wave should go positive first, zero-cross, then go negative. Also those ripples near the pin could be a problem, almost .5v peak to peak from the look of them, which could be interpreted as a trigger by the ecu. Just so I'm clear, you're getting nothing for triggers in the trigger log for secondary trigger? Next thing to test is you can ground out the signal pin for the secondary trigger which will effectively make the ecu think that the cam is always in window. the engine wont run that way but it will at least rule out phasing between the dizzy and the pin signals. alternately you could show me a dual port trace of cam and ref pin pulses on the same graph.

[TheArchitect]

Looks like you are getting cross talk from other targets on the flywheel, or the starter gear teeth signals are somehow bleeding into the ref pin VR output. Such contamination would mess up the crank TDC synch but SHOULD NOT keep from seeing triggers.

The polarity of the signal is EXACTLY what I expected, amplitude is excellent minus the garbage on the sensor signal.
If your ECU cant pick that signal up then I'd start looking at the signal at the ECU connector pins or in the ECU itself.

[TheArchitect]

the trigger voltage looks good, but the polarity looks backwards.

You sure about that?

From my work on decoding the 135 tooth flywheel, the starter teeth have a negative going zero crossing, the TDC ref pin had a positive going zero crossing.

His picture clearly shows positive going zero crossing points which is exactly what I expected.

[Marc]

yep pretty sure.

[TheArchitect]

I think that drawing may be in error.

Even the VEMS folks described the inconsistency in VR polarity between the crank and ref pin VR sensors.

In any case, I spent some quality time with a 4 channel scope, watching the CAM index, flywheel sensor and the TDC sensor and found the polarity to be opposite on the ref pin.

Just sayin.

[Mcstiff]

Okay! I jumped the Hall and got signal!! I set the hall last week but I guess I'm back to that :dur:

Attachment ( 31211 ) : TRIGGER$.JPG

[Mcstiff]

Since I feel like I'm cruising on the failboat, does this look correct?

[Dave]

looks correct, and looks like a newer rotor would be welcomed.

[Mcstiff]

looks correct, and looks like a newer rotor would be welcomed.

Why? It is not doing anything, I am just using the dizzy for it's hall

[Mcstiff]

So looking at the hall, I'm not seeing much on the scope but the signal has a constant 4.49v during cranking. What should I be seeing/looking for?

[TheArchitect]

So looking at the hall, I'm not seeing much on the scope but the signal has a constant 4.49v during cranking. What should I be seeing/looking for?

should pulse to a voltage less than .5v when the pin passes the sensor.