I got my newly built motor, and MSnS (v3 board, v29q2 firmware, low impedance 450cc injectors in peak and hold mode, running spark off MS board, Zeitronix WB) setup to start the car on the FIRST crank! It took me a little bit, but after about 30 minutes I got the car purring as smooth or smoother than stock.

I have the stock ECU controlling my Jeep TB's IAC motor, and it keeps the RPMS VERY steady, running 8* ign timing at idle, and ~14.0 AFR.

I kept on getting this intermiddent super rich condition at idle, which would make the engine studder and almost die. Turns out the default Accel Enrich settings were causing the Accel Enrich to trigger, so I just raised the threshold, till it stopped triggering.

I only drove it down then back up the driveway, but let me tell you IT WAS AWESOME, hahaha.

I'll be starting my actual driving tune tomorrow.

Special thanks to Matt (XtremeRS) for hooking me up with his base ign table, and gilee for asking a lot of questions so I didn't have to ;)

That slight .1v TPS change that would happen every now and then is due to the engine vibration from the Prothane motor mounts, and solid front mount.

Just pull up the realtime window to track down what's going on if you're having idle problems.

Nice! It's a good feeling isn't it? Now you will find yourself with the laptop out all the time and making adjustments here and there...on a daily basis lol.

Originally posted by WickedESi
That slight .1v TPS change that would happen every now and then is due to the engine vibration from the Prothane motor mounts, and solid front mount. Just pull up the realtime window to track down what's going on if you're having idle problems.

I don't have the msns...yet }( but I can concur that the .1v TPS voltage change does happen. I've got the Prothane mounts also, and I notice on my SAFC that the TPS fluctuates from 0 to .3 to .6% and back.

Glad to hear of another MSNS success.


http://www.dsmregistry.com/detail.php?carid=1185

If you ground the TPS ground wire to the MS it helps with voltage stability.

I'll do that. I think it's from the actual throttle body vibrating though, it doesn't seem to be changing fast enough to be noise, but I'll still try it.

Thanks for the tip.

Good to hear you got it going!
Are you only doing Fuel right? no spark right now?

I bascially got my Fuel all tuned right now! Very happy! Since I rebuilt my engine, I cannot get it to boost for longer than 5 sec. EGT will shoot rocket high.. now I boost all day, and it's below 1520F. (only 8-10PSI right now) I love it as well! so you will love it when you start tuning it!

I gave up on the spark for now. Just switch back to my Stock ECU. Somehow whenever I use spark, the car will JERK like crazy when I get to like 3000RPM and ~70-90Kpa. it jerk so bad, it's not drivable. but as long as I keep the acceleration super slow and RPM low, I can go up to 50mph or so. very odd.. I just cannot figure this out yet. so if you got to SPARK, and it works, let me know wick!

BTW, about your TPS, after the first try out, I also tapped and ground the TPS to my MS. and it has as solid as a rock! try that, it might help alot!

For my RPM... It just surge like crazy! I already replaced the crank wiring with a TV coxial cable (shield to MS ground) and I also used a 0.1uF capacitor at C12 to absorb the spikes... but still no good. I just don't know what I can do for that either. you have tthat problem? The RPM spikes usually happen once I get above 2000RPM or 2500RPM.

Good luck with your tuning! I am still trying to fix small things here and there. But overall, I love it! felt like my car is STOCK TURBOED! very smooth!

Enjoy!

Its good to hear you finally resurrected your car, I'm really excited to hear what your car can do with such a nice turbo and now a nice engine management system to match :D

I really need to get on installing my MSnS..

Originally posted by gilee_8
Somehow whenever I use spark, the car will JERK like crazy when I get to like 3000RPM and ~70-90Kpa. it jerk so bad, it's not drivable. but as long as I keep the acceleration super slow and RPM low, I can go up to 50mph or so.

Hey, I went out for my first tuning drives today I am using spark, and having this EXACT same problem.

I took some datalogs, and just installed the viewer, and MSTweak. I'll see what I can figure out.

Yeah, I found the problem looking in my datalogs...

Getting tach spikes once getting to around 2500 rpm's...

I ran a damn shielded pair to the crank sensor (signal wire, ground to MS, and wire shield ground at MS only), and it still get's damn spikes.

Yup... that's the problem .... I did more tuning and logging today to see why running spark is horrible. and what I can only think of the problem is the RPM SPIKE! seems like whenever the SPIKE happen, the car will lose power (coz now MS control the spark) so the problem is whenever the RPM goes above 2500RPM or so, RPM SPikes goes so random and often..

I also shield the SIGNAL wire from the crank position sensor. But did you completely CUT off the sensor and applied volts and ground for the sensor? I only connected one shield wire to the crank sensor.

DAMN how others get their SPARK going!... shoot.

Gilbert

I sent the ground to the MS, shared the signal, and the +9v comes from the stock ECU. If I don't share the signal,

I tried to run tonight with spark hooked back up to the stock ecu. I was still getting those random HIGH rpm spikes above 2500 rpm, which causes the car to buck and want to die from the burst of fuel, and so I'm unable to go abouve 2500 rpm. Did you connect your MS tach signal to the stock ecu tach signal out to get your car running good on stock ecu spark?

OK, well, here is the thing.
first. make sure you have the REV LIMITER turned off. make sure you have the RPM set to like 25500 for soft and hard cut. the reason is, when RPM SPIKES, it usually goes to like 15000 so if you set the REV LIMIT to like 7000, you will keep getting fuel cut, or spark or both cut!

Change that.

Now, when I did my SPARK setup, I got an extra connector for the coil. so I can switch back to STOCK ecu anytime. if you have the REV LIMITER set to MAX high, then with just fuel, you will not feel the buck! the RPM will still SPIKE! but you won't feel it. (check out hte other post that corbin posted) it's the same problem we are having!

But the reason when running spark, we feel the BUCK, because if the RPM SPIKE, the one ignition it changed or missed we will feel for sure! but when RPM SPIKE when only running fuel. a miss of fuel won't make a big difference for us to feel the BUCK.

So I believe our MAIN problem now is the RPM SPIKE problem.
And I tried EVERYTHING I can think of already. up to 0.1uF capacitor, and shield cable. I will try to ground the crank sensor as well to the MS and see what it will change.

So which wire is the ground for the crank sensor? do you remember?

Thanks.

Thanks for the rev limiter tip, it just made my car drive great!

Have you tried getting your tach signal from the ecu tach output, and not the coil? Do you still get spikes?

Are you sharing the the crank signal with both the stock ECU and the MS? This will cause noise to be soaked in from the non-shielded stock crank signal wire.

Each of these questions are important to me, as I'm trying to figure this thing out for us. I cutting the crank signal to the stock ECU would put it into complete standalone mode. You would have to have the MS relay switch on the ASD relay to power the injectors and coil, because it won't if it doesn't see a crank sensor, you would have to try powering the crank sensor with 12v, you wouldn't have IAC control because it wouldn't think the car is running. None of this is really a problem though. I just hope if I do all this the noise will disappear.

good to hear it helps. so now you turned off the REV LIMIT. your car is good to drive? no more bucking? or just less bucking?

So right now. I TAPPED a wire directly from the CRANK position sensor adaptor (behind/below the engine) straight to my relay board. I will have all 3 wires from the crank position sensor hooked up to my stock ECu. the one wire I tapped to the CPS, is using a TV cable shield wire.

So are you tapping it directly from the CPS? or you just tap a line off the STOCK ECU wiring?

I thought the stock CPS uses 9V? will 12V kills it?

PS. also, from reading more on the MS site. I believe the JEEP 4.0L IAC can be controlled by the MS. so I am thinking... totally disconnect the CPS from stock ECU. and use the JEEP throttle body with the Jeep 4.0L IAC to control all my MS. will that work?

Coz I don't want to have a IAC problem.

Yeah my car is running good now, no bucking or anything!

I still want to get rid of the rpm spikes and use spark though :p

I am tapped into the crank sensor signal at the crank sensor, it still shares the signal with the stock ecu, which is probably where the spikes are coming from. The crank sensor is grounded ONLY to the MS, and the 9v comes from the stock ECU.

I heard 12v works, but I wonder why Chrysler wanted to use 9v...

You said you car drives fine now. you mean with SPARK & FUEL it drives fine with no buck?

OK.. so now your setup is the same as mine... you used shield cable all the way to the CPS and tapped into there. then you CUT the ground wire of the CPS, and connect the GROUND wire to the Megasquirt Ground. and you leave the 9V powered by the STOCK ECU. is that what you have setup right now??
-STOCK ECU only connected 9V and signal to CPS
-MEGASQUIRT only connected signal and ground to CPS (am I correct on your current setup?)

So if it is, I guess the only difference now from mine to yours is the ground wire. I will try that this week!
coz even mine without REV LIMIT, I still cannot drive my car with SPARK coz it bucks! But I will try it out again tonite. coz last time I had my REV LIMIT set to 17000 only when I try my SPARK. maybe I should change SPARK again since now I set the REV LIMIT to 25500.

Thanks Wicked.

I have spark runnin of the STOCK ECU right now because of that bucking from the rpm spikes.

You are correct about my setup, my crank signal and ground to the megasquirt is a shielded pair, meaning they are both inside the wire shield. It's using an aerospace quality teflon 22 awg shielded pair (which I got from my dad who works at NASA). The noise I'm sure is coming from the stock ECU still being hooked to the signal wire.

Damn... your dad works for NASA. sweet man!

Ok. I was mistaken. the reason I keep asking because I thought you got your car running FINE after turning off the REV LIMIT. (fine interms of running fuel and spark)

But I got it straighten out now!
So I guess we have to disconnect the STOCK ECU from the CPS. but can we still have the stock ECU to suply the 9V but we just cut the ground and signal away from the CPS? or the stock ECU will no longer supply 9V to CPS if it doesn't detect the CPS anymore?

Damn, that means I need to try out the JEEP IAC to get the idling working off of the MS.

Right it won't supply 9v. You probably don't want it supplying the power anyway, may have noise on that too. As for the IAC stuff, I run smoothest once I disconnect the jeep tb IAC after I let it adjust once. I remember XtremeRS saying his stock IAC moved out once he hit boost, so it would loose it's idle.

The best method would either be seeing how to get the MS to control the jeep IAC since I've heard it's been done.

I don't understand what the deal is with tach spikes on the V3 boards...I dont use any shielding of any kind on my tach input wire, I just tapped into the crank sensor signal wire at the stock ECU, and I have no spikes what so ever...Only difference is that I run the version 2.2 board. I really think it's something in the design of the v3 board that either doesnt like our tach input signal from the crank sensor, or its just that sensitive.. If you guys can try this, maybe competetly disconnect th crank sensor from the stock ECU, ground it to the MS main ground, and try using different voltages to power the sensor. Try 5 volts, then try 12 volts. You wont damage the sensor with 12 volts. I'm wondering if the output voltage from the crank sensor is either not enough, or maybe too much from the 9 volts stock. You can get 5 volts from many places off of the MS PCB, and 12 volts is simple to get anywhere from the car or MS power feed. Try 5 volts first, and see what happens, then try 12 volts.

man, not what I want to hear, finally got off my ass to build my MS...V3 too. should have bought that 2.2 for 100 less.

I just hope V3 doesn't have a design problem!
I just hope the stock ECU interfered with the CPS signal.

But then matt said he also had this CPS connected to both MS and ECU but still no SPIKE.... worried.

yeah, but the neon guys are almost triple in numbers (running MS) then us and I have yet to see a post about this with them.

Neons must be good luck then.

Now that I've figured out how to wire it so I don't have noise (in my other post). It's never driven so good.

It's unbelievable that at 185-185-185-185 compression (8.8:1 pistons) at 3.5 lbs of boost my car has more power than it did with the stock 9.6:1 pistons and stock computer with a SFMU at 7-9 lbs.

It just drives so damn smoooooth, and part throttle boosting is something I've never experienced before until now >:]

grats man, Although I have seen posts of people going standalone as well. Who knows, Ill search some more.

I Hope Corbins mods work well enough for me. Looks like those that do have MS running are all on the v2.2 board.

My engine is broke in, I switched to synthetic, and cranked the boost to 17. Ohhh man, it pulls HARD and the motor runs soo smooth. The MegaSquirt rocks my socks! I can't wait to get some dyno numbers and track times.

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