pmrobert,
Appreciate your input. Lucky your in FL it was 7 degrees here in NY this morning! Now thats a serious cranking pulse width test! I measured between my chassis and engine with a DMM and my resistance is 3 ohms without a ground strap because of my solid metal engine mounts I think. I also put a extension on my meter leads and measured from the battery negative to the front passengers headlight and got 2 ohms. So that tells me different places can make a difference but not much. My MS was working but had intermitten problems with loosing spark. Im still working on my solution above (well Muy's solution). Phone keeps ringing...time to stop answering it, Shawn

 

3 ohms is actually quite high, as is 2 ohms... you should have maybe .1 or .2 ohms (within the margin of error for your DMM I'm sure).

mike: there was no thread for ddub's problem, I talked to him about it on IM. I was thinking maybe the starter was introducing some kind of EMI when the MS was grounded to the battery... moving the ground to the engine solved the problem for him. The VR sensor conditioner circuits are all fairly sensitive.

 

I made all the changes we talked about. After the changes I still didnt have spark. I checked the daughter board with the lm1815 ckt for power and it had 4.88 volts supply power. I then adjusted the pot a bit counterclockwise and finally got spark again. I adjusted it before like you told me..it shouldnt have moved. I had it running for a hour plus and got the idle down to 950 bounces to 1000 on occasion. I also finally got the timing set right,that also helped smooth out the idle. Im idling close to 1000 RPM at 10.34 AF ratio and leaner and it starts to stumble a bit. I did check my new plugs after running for a hour and thier black as hell already. I also set the staging point for the secondaries to be MAP based and to come on at 50kpa and above that seemed to work well. Watching the graph and wideband and revving the engine it revs quite snappy and dosnt lean out. A few more days of tuning and I'll take a easy drive keeping out of boost. Also depends on if the weather cooperates. My coolant temp guage finally reads correct as I grounded that to the rotor housing a few inches from the main MS ground. My air inlet temp sensor is also correct reading around 104F during all of this. My coolant reads 186 when the fan kicks on. My idle duty cycle is around 2.2ms on the injectors. Im not sure I'll be able to get the idle much lower with these 720cc injectors. Im ok with 1000 RPM idle. I am impressed with how snappy it revs. It actually moves the car a bit. I just hope the snow/ice stays away this weekend so I can drive it finally! I also grounded the VR ckt and all shielded CAS wires to the engine block. I also loomed all grounds seperate from power wires. I think I finally have this thing sorted out . Thanks to everyones help here,Shawn

 

I forgot to mention I am happy as hell! My neighbors are not so happy with me but oh well. Im actually thinking of canceling a date with the GF this weekend so I can tune more and drive this thing. I have issues I know. I also noticed removing the MAF meter really wakes up these engines. I now just have a 3" pipe from the turbo air inlet to in front of the radiator with a K&N filter. Im also thinking my idle is stubborn to be lower and smooth because I have a light alluminum flywheel. But if thats the tradeoff thats fine because it revs way faster than ever! Very psyched and will be dreaming of VP racing fuel and high boost Im sure,Shawn

 

good! That's weird about the POT.... I guess it was making your tach signal intermittant, keeping you from getting spark. It's just weird that it somehow moved.

Also, that news about your idle is a bit weird as well, as the NA rotaries that I've tuned like to idle around 12.2-13:1, with an advance of between -5 and 3 degrees. Tofuball and I both have our idles set at 800 rpms, and the engine doesn't move at all... Tofuball even has a lightweight flywheel. The point is that you might still be able to get the idle lower.

the throttle response increased a lot for both me and tofuball as well with the MS. I did a comparison on my other friend's rx7 with my prototype plug 'n play unit... Basically we hooked up his stock computer, and revved a couple of times... and it was pretty sluggish.... put the MS on and rev a couple times, and it revs EXTREMELY quick.... almost like a different engine... and that was with the AFM still on (because it needs to be there to turn on the fuel pump if you don't rewire it, and we didn't want to rewire his car for a simple test).

Anyway, glad to hear you're finally making good progress.

 

Roger that, sir! (with apologies to renns!)

-Mike :-)

 

Well this engine should idle with the same parameters. Its a 6 port 13B completely stock internally and has a cartech turbo kit. It goes down the high compression low boost theory. It is recently rebuilt. I'll have to keep experimenting with the idle advance and AF ratio to try and lean out the idle. I dont care about making it nice and low but I do need to find a way of leaning it out..its destroying plugs daily. Plus a idle that rich sure burns a lot of gas. Premium gas is up to 2.75 a gallon here. My goal is to be faster than my friends VW cabrio 1.8 liter turbo running a EMS stinger ECU. Just a on going game of one upmanship between us for the last 15 yrs. I'll check megatune for the idle advance I think I saw a feature to adjust it. Shawn

 

How do you set the idle? Screw on the throttle body? MS setting? BAC control after warmup? My idle is a little under 700 RPM with the throttle body screw all the way CCW - I'd like to raise it. MS is set to only use the BAC during warmup. I'd like to use it hot, but haven't yet figured out the settings (perhaps you could share your settings if that's how you set the idle). Once it hits 160 degrees, it's tough to keep it running until it warms up some more.

On another note, tonight rotor #1 decided it didn't want to play any more. I can attest that a 13B will run on one rotor, but it sure won't idle.

Thanks,

 

Eagle7,
I had issues with the BAC ckt and just stopped using it alltogether. I use the small screw on the throttle body and raised my idle that way. Its simple and it works.
Muy,
You arent gonna believe this,I lost spark again!!! I know its not a wiring issue I just traced out every wire and regrounded everything last night. Everything is soldered and heat shrunk no chance of a bad connection. This I am 100% sure of.
It seems to start on occasion and run for as long as I want. Once I shut it off I usually dont get spark again. Its done this 4 times now. Whatever the problem is its been here from the beginning. Remember I also upgraded firmware and the problem was here before and after the upgrade. I even replaced the plugs again tonight. I am getting a RPM reading in megatune and when not cranking it now says 7 RPM. It use to rest at 2. This time Im really stumped. I have 2 different things Im thinking of now. 1 is to send this MS to someone very knowlegable and have it tested and repaired as well as check the firmware. 2 is to use a first gem electronic dizzy for ignition. I know your not a distributor fan and neither am I but at least they are reliable.
I also traced out each wire going to the coil packs and found no problems or bad connections. I also checked for power at each coil pack,no problem there. I also populated the daughter boards 2 VR conditioner section (lm1815) and switched to that ckt..no change. I switched back the the 1st lm1815 checked the wiring and tested for 5volts at the board...still no spark.
At this point I know its not the wiring,firmware,coil packs or the daughtercard. That leaves a intermitten problem inside the MS itself. If theres someone preferably Muy who can and will repair this my email is Azenis29@aol.com and can pay with paypal once we talk about costs. Im sooo disappointed,Shawn

 

I cant sleep this MS is really bothering me. Im thinking of buying another V3 kit and starting over. I really dont want to spend any more time troubleshooting. Muy may remember my fuel pump ckt never worked from the MS either. Im thinking theres a defective chip on my MS board. Would probally cost almost as much finding the problem as buying another unit. I cant see how the problem could be anywhere but inside the MS itself. I have checked all grounds,wiring..firmware settings etc etc. A coil is either bad or good it dosnt work one day not the next and then work again 3 days later. Everything points to a bad ckt inside the MS. Any ideas? ,Shawn

 

Have you reflowed all solder connections? Is there any visible flux on the board? If there is flux visible on the board you can clean it by one of several methods, I prefer grain alcohol (Everclear) and an old toothbrush. Flux can cause all kinds of wierd, intermittent problems. This may have nothing to do with your problem but it cannot hurt to check and only takes maybe 30 minutes total to reflow all joints and give the board an alcohol douche.

-Mike

 

Ok I may have a idea for you Custom13B. I have seen Pots go high resistance on many occasions and is some cases the wiper arms inside lose tension or get dirty. I would have a go at replacing the adjustment pots on the VR board or you could have a crook CAS too. If you just interchanged chips in the VR circuits I would look closely at the pots. I will also tell you I am not a MS man but I do work on electronics for a living. I have always admired people who have a go at doing it themselves. I hope you sort it out.

Cheers
Michael Smith
13BT TII with Wolf 3D V4

 

I've not had any reliability problems with the MS doing ignition. Tofuball's is so reliable, it's become his daily driver....

If there's a problem with spark, it cannot be software. There MUST be an intermittant problem with wiring or with the soldering inside the case. Sometimes if there are intermittant tach-signal problems from the CAS, wheel-decoder settings of 12,2 and 6,8 won't work... but 1,3 7,9 will... you could try restabbing and using those settings.

I've never had a problem where I get a tach signal (and it shows up correctly in megatune) but I don't get spark.... which really makes me think that something is going on with your vr sensor conditioners. Even when I've gotten nasty tach spikes (from bad grounding/unshielded wires), the spark plugs have fired. The only time I've been able to get the behavior you're describing is when I had a bad/intermittant ground which was causing an intermittant tach signal. I'd see accurate rpms in megatune, but no spark. what happens is you get a little bit of a signal, megatune displays rpms, but the signal drops out for a second or two before coming back again. Megatune won't immediately drop to 0 in that case, so it looks like a steady tach signal.

When you crank without spark, does the rpm number update very fast like when the car is running? or very slow ?

Ken

 

RPM are exactly like they always have beenin megatune. I have defluxed the entire board including the daughtercard. I have also reflowed the solder joints everywhere including the wiring on the car. It is not a wiring or ground issue . I just check those for the 10tyh time. I even made a new engine ground strap. I also built the second VR lm1815 ckt on the D board and tried that so the pots arent the issue either. Im at a point where Ive tried so many things there is nothing new left to try. I will check the D boards pots again and try adjusting them and check the grounds. My D board is grounded to the engine now. I agree I think the issue is with the D board somehow. I mat try the second lm1815 ckt on the d board again and try grounding it somewhere else maybe. Not sure and I getting to the point where I dont want to try anymore.

 

how are your pots adjusted though? if the resistance is too high, you'll have problems.

It really sounds like you have some kind of really simple intermittant problem.... Have you tried resetting the wheel decoder settings like I said?

As I said earlier, I've seen cases where if the signal from the G wheel on the CAS is a little noisy or intermittant, the 12,2 6,8 settings won't work right, but 1,3 7,9 will... (I just saw this issue last night). It really sounds like the MS is missing the return teeth and not firing the spark plugs.... which would point to an intermittant/noisy signal from the CAS.

Can you send me a datalog of a crank where you're not getting spark? And also an msq, along with the version of the firmware you're using?

I'll take a look tonight or tomorrow and at least tell you if you're having software or circuit problems.

 

When you say you're using a 7ms cranking pw, at what temp is that? With 720cc injectors and stock 13b manifolds, something close to what the FAQ has, and adjusted for your injector size should work very well.
When exactly do you lose spark? Is it only if you turn the car off then back on? If so you probably are flooding it out somehow. I have had a problem with hot starts as well and using Time Based cranking solved my issue, but the way it determines cranking rpm can cause some real engine problems if there is an issue with your starting system. Restabbing the CAS like muythai said should be your first step.

Does it ever loose spark as you're driving or at RPM? Or does it simply stall out while idling? Also, how are you determining you're losing spark? Just curious.

This really sounds like a settings issue to me. Even though I had starting issues at first, I never had any sort of problem while driving or idling once the ASE and warmup settings were correct, so MS ignition is very solid as far as I'm concerned.
We really need to see a log, or your MSQ file at least to help much further.

 

I think he said earlier that it runs fine for as long as he wants, then when he turns it off, it won't get spark when he turns it back on....

I never actually asked how he was determining he had no spark though... I was just taking his word for it

 

Ok Muy I think its worth a shot trying your CAS settings 1,3,7,9. I understand about the pot adjustment Ive tried many different settings on them. Im also thinking about this daughter card and how its wired. It gets 5 volts from the MS. I have it getting the 5 volts from the proto erea grounds there as well. The shielded CAS wire comes in to the daughter board and I have the shielding grounded to the engine block. Should I have a additional ground from the daughter board to the engine? Just wondering.
Jayroc, I appreciate your suggestions and Im not trying to be rude but I've already been there and done that. My CPW is now 6ms and that works well for me. Flooding is not the problem,I have absolutely no spark with bran new spark plugs. I have checked for spark with a snap on spark checker and also watch the LED closest to the serial port. If that LED dosnt flash your dead in the water. This problem is totally intermitten the last time it ran it lost spark at idle and fell flat on its face,,hasnt run since. I havnt tried driving the car its in my garage. Frankly I dont trust MS enough to be driving it anytime soon. My timing is spot on. My 6 ms cranking pw is the main setting and all the other values arethe same as the FAQ. Almost time to go swear at the car,Shawn

 

I'll try and datalog while cranking in a log file and use my nice new neighbors wireless network to get it online...lol. I may just go and have a few drinks tonight,this car is sending me over the edge.

 

your wiring of the daughtercard looks fine...

Just a quick question though... which of the lm1815 circuits did you use? the one with a 39k/56k resistor? or the one with the 82k resistor? Just trying to cover all the bases. The circuit with the 82k resistor outputs a wider pulse... if you're using the other circuit, you could be getting intermittant problems because the G wheel pulse isn't long enough.

You shouldn't need to ground the daughtercard stright to the engine... also, I don't know if it makes any difference, but I do have my shielding grounded to the MS on one end... You could be picking up some interference there I guess.

 

Well Muy Im using the top lm1815 ckt on the daughter card like you suggested in the FAQ. I switched to the lower one last night with no change but I didnt mess with it much.

 

Muy, On the wiring directions for the D card is says,the upper ckt is for the base wheel(24) pin wheel. And the lower ckt is for the 2 pin reset wheel. I still dont know what ckt usus what resisator but think from this I should be using the upper ckt correct?

 

I was going to try to confirm absolutely for sure that the "top" one is the 2 tooth circuit, but it appears that all the online diagrams and instructions for this card have disappeared... so all I can tell you is to look at whatever docs you have for that card and make sure that the 2 tooth wheel is hooked up to the circuit that has an 82k resistor.

 

Also, if you have a chance, and a camera, take some fairly close-up pics of your board, top and bottom... I just want to verify all is as it should be.

 

Another possibility is that one or more of the processor's outputs are flaky. It doesn't take much to damage these; Motorola docs indicate a max of 10ma I think. 1 inadvertent 12v spike or alternator load dump will kill these outputs, don't ask how I know. It's a $12 chip, perhaps you might try a new processor. Don't give up!

-Mike