3100 DIS issues

[Maverick H1L]

Well, I ended up taking my spare crank gear and putting it on top of the damper for reference, taking a pic, and sending that off to BCC as well in a second email. The damper is completely FUBARed. The #1 TDC and SYNC notches are almost 100* clockwise from where they should be (20* counter-clockwise from factory timing mark and they should be 120* counter-clockwise from the mark, which should no longer exist).

BCC sent me back another email, apologizing, saying that the damper was put in the holding machine upside down and the person running it should have known better than to let it go out the door (I hope he has been either reprimanded or canned). He sent me a full refund for the cost of the DIS trigger kit.

:edit: Anyone need a spare or replacement DIS module? I've collected 4 of the things now... I'll test each when I get the damper straight (although I'm pretty sure they all work properly). If anyone wants one, LMK. I'm keeping one just in case along with a set of coils and the other Camaro 7x, but the FWD 7x is still available as well, for a limited time.

[Maverick H1L]

Just one more question:

Does the 3.4 as installed in the F-body have a timing scale? I'm assuming it does since the damper does have the factory timing light notch in it. If it does, where is it located? I haven't seen a good enough pic of the 3.4 timing cover to know for sure or not. I always thought that the 24X was mounted in place of the scale?

Once I have the answer to this, I'll be able to definitively send out the info to BCC.bccdamper.jpg

The pic is of the BCC damper on my template. The angle is slightly off (I thought I was straight over it but I guess not), but you can get the general idea of how off it is.

[caffeine]

Have you contacted BCC about this? Hopefully he will fix this for you.

[Maverick H1L]

Okay, I see I'm still talking to myself, so I'll bring up a point...

I ended up making a template to gauge the notches for the trigger wheel.

The BCC trigger wheel is INCORRECT. They have the #1 TDC notch correct. They do NOT have the other 5 correct. They base those off of the #1 sync notch, so each one is 10* retarded. Or they have the #1 sync notch advanced 10*, however you want to look at it. It's still WRONG.

I ended up taking a spare damper (yeah, I know, warning about slipping on the outer ring but it's all I've got for the moment) and cutting the right notches into it. I now have spark and DRPs going to MSII. It's not going to run without a new battery (life support has failed).

[Maverick H1L]

Okay, new question...

To anyone that either has a spare crank or is in the middle of a rebuild...

How deep are the notches in the reluctor in the middle of the FWD crank (for the 7x)? I already know that GM has cut them with SQUARE edges, but how deep? The notches in the outer ring of my damper seem to have been cut with a mill. And they're not very deep and they're NOT square. I'm thinking that they aren't shaped quite well enough to be triggering the module(s) properly. I'm also thinking that maybe I could take and cut them slightly deeper with a reamer after removing the damper from the crank (reamer is the same size as the notches), since it seems that the notches are only about as deep as half of the reamer.

Any advice here?

[Maverick H1L]

Update:

Now I'm more thoroughly confused than before.

1. Hooked up the battery to a running car as a jump start. Voltage stayed above 11V.
2. BOTH modules test as working on the JimStim in 7x trigger mode. Spark, tach pulses, DRPs, injectors firing, the whole nine yards (yes, I did disconnect the fuel pump relay so as not to flood the engine)
3. Got a flow chart for the DIS. 7x sensor tests as good both in resistance (over 900 ohms) and output VAC (1.5V+). Both of them (bought another just in case).
4. Found a problem with the yellow 7x wire. Rebuilt the wiring (yes, I did twist the wires together) and resistance is nil (stupid meter never wants to read 0 ohms even with the leads connected to each other so I can't be 100% sure on anything but the test read well under 1 ohm).

When I hook up the 7x to both modules I get NOTHING. No spark, no squirts, no tach signal, no DRPs to MSII. Nothing. Flow chart says to replace the modules, which I am trying to do but certain eBayers don't seem to want to ship after payment has been sent. Since it looks like I'm going to need to head back to the junkyard (as I can't seem to find ANYONE who wants to sell me the exhaust hangers I need), I'm probably going to explain that the module I already bought there doesn't work and I want to see the engine I pull the next one off of actually RUN before I pull the module.

It almost seems like the modules aren't decoding the 7x signals properly. If I could, I'd get my hands on a scope and check the 7x output, but $300+ for something I'm probably only ever going to use only ONCE is kind of steep.

Does anyone have the BCC 7x kit or something similar? I'm wondering if maybe I did something wrong... Seems pretty straightforward... Put the notched damper on the crank. Buy 93-95 Camaro 3.4 7x sensor (since it doesn't come in the kit) and put in bracket. Bolt bracket to front of engine where lower AIR pump bracket bolts to. Hook up 7x sensor wire to sensor and module. I did have to space the 7x bracket away from the block using thick washers (torque arm hardware) because the 7x seemed to be right at the back edge of the damper notches where the notches end (they don't cut them all the way from front to back on the damper ring for some reason), so I could make sure that the 7x was in the middle of the notches.

[Maverick H1L]

Bringing this back in case someone else comes across this issue...

I am now 100% positive the problem lies with the system voltage.

Earlier, I took my JimStim out, just for kicks, to hook up to the 7x sensor input on the module. Which, in the 7x wheel mode, would simulate the engine being turned over, without the starter drawing the battery power. I hooked the TACH wire on the stim up to the pin on the ignition module would be occupied by the 7x yellow wire, plugged the stim in, and turned it on. What do you know, I turned the RPM pots on the stim and doesn't everything light up and work just fine? Fuel pump runs, injectors fire, spark plugs fire (spare plug hooked up to #1 wire).

I'm getting a new battery next week. Hopefully by then I'll have this drive belt figured out...

[ericjon262]

if you're 100% on the wiring, get one off of a running car, and try that.

[Maverick H1L]

Well, let's see... The first I'm not 100% sure about. The second came from an unmolested car that was crashed, so I'm assuming it was good enough to power the engine when the impact came.

I'm going to have to wait a week to try another battery. I'll finish my testing with the one I currently have. It appears that when the voltage drops below about 12.4V, the module stops sending the signal. And since that is currently pretty quick once the starter starts doing its job, the signal doesn't last long.

[ericjon262]

have you checked the ICM against a known good module?

[Maverick H1L]

The thing is, I've been trying for a solid week... I even went on Thursday and got the replacement coil pack. I've tried jumper wires straight to the battery for the ground, I've checked all the wires several times now, I've put the MSII back on the stimulator to double check the tach input, and everything I've gotten out of it is that the system SHOULD be working just fine even with the crappy battery. As was asked on another forum, the MSII is NOT resetting with the power dropout.

A few minutes ago, I went and unbolted all of the grounds on the back of the engine. I cleaned EVERYTHING to nice and shiny, both bolts, the nut, and every single ring terminal. I'm going to try it again in a bit and we'll see what happens.

[caffeine]

I dunno; I haven't had any issues like that but I've also never gone tried to use it with megasquirt. I would think if you're sure the ICM is working properly and sure the wiring is correct then everything should be fine.

[ericjon262]

I did a little looking, and it looks as though the modules interchange completely. I'm not too keen on the inner workings of the module or MSII.

try hooking up a charger and trying again.

[Maverick H1L]

Yawn... I feel like I'm talking to myself.

What is the lowest battery voltage the 3100 module can handle while still producing DRPs? My battery is SHOT. I'm only keeping it alive using a battery maintainer. While cranking, the system voltage drops, but NOT below 11V (I'm not cranking it for that long).

I've redone all the wiring on the large connector now. I've redone the ground twice. There is still plenty of power on the power wire. I'm still getting spark and only an initial jump in the DRPs as indicated by the MSII. If the 3100 module is more voltage sensitive than the distributor I took out of the 3.1, it would help me to know.

I have had my alternator fail before while on the highway. The system voltage dropped under 10V. The engine was misfiring badly but STILL RAN until I shut it off (and then it didn't restart). That was with the distributor. I find it quite hard to believe that the 3100 system is THAT much more voltage sensitive that it won't produce DRPs but will still produce spark with the system voltage under 12V. Can someone shed some light on this?

[Maverick H1L]

Um, possibly a dumb question, but...

Is there a difference between the modules? I'm talking between about 1988-2006 or so? I know the one I got from the J/Y yesterday is off of a 3400. I didn't check the year, unfortunately (I'd guess around 2005-06, was a crashed Malibu of 2 gens back from the new ones). Would I have better luck going to an older module (say, from a 2.8-3.1 FWD or a 3.4 Camaro if I can find one)?

Still have lots of spark. Still have power to module and much better ground now that I've cleaned everything up and replaced the ground wire on the module. Still only have an initial bounce of the TunerPro MSII tach when first cranking and zilch after that.