Cascade Crew

alloy · Posted: Sun Sep 12, 2004 9:39 pm Post subject:

Anyone got a spare memcal I could try for a few minutes?

I'm getting desperate now Sad

iansane · Posted: Mon Sep 13, 2004 1:09 am Post subject:

Where you located? What year car?

alloy · Posted: Mon Sep 13, 2004 6:38 am Post subject:

Vancouver, WA, 87 with 305 TPI 5 spd.

Dewey316 · Posted: Mon Sep 13, 2004 6:40 am Post subject:

do you still have the moates adaptor?

if you do, i can burn a chip for you, and drop by. I just need the specs, 87?? 305-speed?

alloy · Posted: Mon Sep 13, 2004 6:48 am Post subject:

I never had a moates adapter. I have an adapter that I've had since 89. I had to de-solder the stock chip and plug the new chip into it. And I've just piggy backed a ZIF socket on top of that to make it easier to change chips.

I beleive I have the stock chip here, the ID on iy is ACXY. I've not tried that yet, I'm thinking maybe the memcal might have went bad. But will try the old chip this morning.

I just can't figure out why the computer is shutting off the power to the ignition. Just doesn't make sense to me.

Dewey316 · Posted: Mon Sep 13, 2004 6:53 am Post subject:

the other thing we could do, is hook the computer up, and see what the computer is commanding timing wise.

alloy · Posted: Mon Sep 13, 2004 7:00 am Post subject:

Well I do have my Auto X-Ray unit I've tried on it, but now unless I have the timing wire disconnected, it pretty much won't even run. So not sure what we could see with a scan. And the car is not drivable at all.

Dewey316 · Posted: Mon Sep 13, 2004 7:04 am Post subject:

hmmm, does anyone know if the ESC module for the TBI cars is the same as the TPI cars, My car isn't going anywhere anytime soon, so if any of the parts match , we can sure pull them on my car and try them, so help find the problem.

I asume when you and paul switched computers, you used you memcal/chip? if you did, we might see if paul has a memcal you could borrow, since he has that fancy holley computer now, he isn't using his GM stuff.

alloy · Posted: Mon Sep 13, 2004 7:09 am Post subject:

Yes I did use my memcal/chip. Paul didn't say if he still had his.

Maybe he will see this and respond.

alloy · Posted: Mon Sep 13, 2004 7:55 am Post subject:

Ok, just went out and played with it a little. Swapped computers, chips, no difference.

I did do a little checking with the X-Ray unit and found that the timing reads 26.6, 27.6, 28.3, 29.7 at idle with the ESC wire disconnected. The timing light confirms that the timing does move. And, is switches from open to closed loop at idle, and when you rev it it stays in closed loop and goes up to 42.5 deg. of timing. This is all with the wire disconnected. With it connected and the the engine barely running, the timing advance stays at 32.5. The knock sensor reads 10, but knock retard is 0 deg.

I was under the impression that with the timing wire disconnected the computer wouldn't control anything, (open loop) and no advance was possible.

Dewey316 · Posted: Mon Sep 13, 2004 8:00 am Post subject:

strange, with the wire disconnected, the computer should not have control of the timing.

alloy · Posted: Mon Sep 13, 2004 8:10 am Post subject:

What else could make the timing move with the wire disconnected?

The timing light shows the timing stays at the base setting, and sometimes jumps up. But the X-Ray unit says it's at 26 deg? I'm not sure what gives here. This just doesn't seem right. I have conflicting readings between the light and the X-Ray unit.

Dewey316 · Posted: Mon Sep 13, 2004 8:16 am Post subject:

the xray is what the computer is trying to command, with the wire disconnected, that should read 26* etc, but the actualy timing should be whatever you initial is (at idle anyway). if it is VERY speratic, you might check for play in the rotor etc. with the wire connect, you should see the timing change to match the commanded timing in the computer.

alloy · Posted: Mon Sep 13, 2004 8:47 am Post subject:

Ok, that makes sense. Didn't know it was commanded advance not actual.

I swapped my original distributor back in and there is maybe .002 end play. I cleaned and inspected the distributor for cracks and play. It's tight and in very good condition with another new pickup coil. I didn't think it was possible for the timing to move with the ESC wire off. There is no vac or centrifical advance mechinism, so how is the timing advancing?

Dewey316 · Posted: Mon Sep 13, 2004 10:19 am Post subject:

I have a feeling, that when we can answer that, we will have solved your issue. Wink

alloy · Posted: Mon Sep 13, 2004 10:37 am Post subject:

Well The timing jumps around a little, but not sure how much with the wire disconnected. My timing light is old (like me Razz

) and no advance mechinism deal built into it to read what the timing is advancing to. So It may be a false reading from the inductive pickup. No way to be sure.

The problem as I see it is the computer or something is shutting off the spark to the engine for some reason. Pull the timing wire and all is good? I can't imagine why it would be shutting off the signal to the mudule, or actually the power (don't know which one). Just seems like this shouldn't be happening. Almost impossible actually.

I called the dealer and a memcal for a 3.08 geared car is still available, but not for a 3.42. I've been running the 3.42 on the 3.08 memcal for 2 years now and no problem. But I have a feeling it's in the chip programming that makes this difference. And I have a custom chip.

Would a real computer instead of a X-Ray unit provide more data to diagnose this problem?

I'm just not sure which way to turn next with this. Should I shoot myself or the car? Those armor peircing rounds sound mighty tempting about now.

Dewey316 · Posted: Mon Sep 13, 2004 10:42 am Post subject:

LOL.

i don't think the computer will give us anymore useful info. some thing things you might look for, is some sort of short on the ESC wire, or something that would cause it to either drop spark, or cause the coil to fire when it shouldn't.

alloy · Posted: Mon Sep 13, 2004 11:37 am Post subject:

Ok, after checking everything yet once again, I think (crosses fingers-hmmm. can't type this way) I found the problem. I went over all ground connections, weather pack connectors, ect. and found corrision on the two ground wires going to the back of the drivers side cylinder head. The ONLY way I could have found this was to take the nut off the stud in the head (a pain) and look closely at the crimp on ring connector. No way to see this without removing wire from the stud.

Anyway, I soldered on a new ring connector and put it back on and tightened the crap out of the nut and it seems to cure the problem. Haven't driven the car, but a bad connection like this makes so much sense to me with the way the car was acting. I just hope this odessy is over now. Was checking Ebay for some of those armor peircing bullets for my M1 Carbine. Wink

And before I forget about it, I want to say THANKS to everyone that donated their time (and parts) to try and help me. I really appreciate it.

Twilightoptics · Posted: Mon Sep 13, 2004 12:55 pm Post subject:

alloy · Posted: Mon Sep 13, 2004 1:02 pm Post subject:

Yes it is a nightmare, and I'd already checked that connection once and it was tight. But I got frustrated and took every connection I could apart and examined it carefully, and that's how I found it. Guess the car wanted to extract a toll from me before giving up it's secret.

And agian, thanks everyone.