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420A MSII Help, Losing Sync Randomly

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95TalonOwner

95TalonOwner

15+ Year Contributor
1,313
27
Oct 18, 2005
Milwaukee, Wisconsin
So I got the talon running on the MSII, fuel only right now until I iron out all the issues. My problem now is that while driving, it keeps "losing sync" randomly which in turn causes a very quick hiccup like a misfire. The MS clock keeps counting so I know the MS isn't completely resetting. I thought it may have been a 12v supply issue or a ground issue so I ran completely separated power and ground wires for the MS unit back to my battery posts figuring that's probably the cleanest I can get. Also, every time it "loses sync" the ASE kicks on and eff's things up for a couple seconds. Any help is appreciated. Thanks.
 
I had this problem too on a friends car, never could figure out what the issue was, ended up removing it and going MS1. When it was on his car the only thing the stock ecu controlled was the fuel pump, fans, and speedo. Best of luck to you, I chased my ass around that thing, never could figure it out, made sure I had a good ground, clean signals everything. Put the MS1 with internal igniters on it and never had another problem.
 
Slo2gen said:
I had this problem too on a friends car, never could figure out what the issue was, ended up removing it and going MS1. When it was on his car the only thing the stock ecu controlled was the fuel pump, fans, and speedo. Best of luck to you, I chased my ass around that thing, never could figure it out, made sure I had a good ground, clean signals everything. Put the MS1 with internal igniters on it and never had another problem.
Click to expand...

Ha well that doesn't make me feel too good. Also, when it happens, the tach needle drops instantly a couple hundred rpm and all the LEDs flash at once. Here's a video of it.

http://i88.photobucket.com/albums/k181/crazdawgtodaend/4ef08d0d.mp4
 
We need an MSQ file and datalog to tell you anything worthwhile. Until you post those files, all we can tell you is generic advice like: make sure your injector settings match your injectors, make sure the ECU enclosure is isolated from chassis ground, disable noise filtering settings, set TPSdot/MAPdot thresholds high to disable accel enrichments, etc..

There's no reason this sort of thing should happen; in other words, it's not an MS2 issue. There are plenty of people with 420A's running MS2 based ECU's problem free.
 
Thats the same thing his did except it seemed to do it everytime right around 5k under a load. I don't have the MSQ because my laptop was stolen but he was running a basic set up with DSM 450's a manual IAC, and stock coil. Was pretty straight forward. I hope you figure it out just because I beat my brain trying to figure it out and everything I tried gave no results.
 
Your injector characteristics are set for high impedance injectors, which will definitely contribute to your problems. You also have your ECU set to use additional injector drivers, which is inaccurate unless you have a SymTech Labs PH Driver board or JBPerf P&H Board, wired for sequential injection.

So the first thing to do is go to "Advanced" > "Sequential Injection". Now change "Injector Drivers" from "Additional Drivers" to "Standard Drivers".

Now, go to "Basic Setup" > "Injector Characteristics". Use these settings for low impedance fuel injectors (tweaking will be necessary):

MS2-Extra Conversion Manual

You might also want to disable acceleration enrichment while you're tuning your VE table. For that, go to "Accel Enrich" > "Acceleration Wizard" and enter 1000 in both the "MAPdot Threshold" and "TPSdotThreshold" fields.

Finally, look into your CLT wiring. It's a little too noisy. Make sure all the connections are solid and its grounded at a suitable location.
 
I actually have Accel high impedance 62lb/hr injectors that Howell Automotive gave me for free since my order with them went so badly a long time ago. Thanks for all the info, it's really helping. Steep learning curve with all of this stuff.
 
95TalonOwner said:
I actually have Accel high impedance 62lb/hr injectors that Howell Automotive gave me for free since my order with them went so badly a long time ago. Thanks for all the info, it's really helping. Steep learning curve with all of this stuff.
Click to expand...
Sorry, I must've been looking at Slo2gen's post when I was searching for what type of injectors you were using. Either way, the additional injector drivers settings needs to be corrected and the injector characteristics need to be fine tuned.
 
And Paul in to save the day, hopefully this works for you. Honestly I don't remember if he changed his additional or standard drivers. May have been the issue the whole time. Either way, this sound like/hope it will work for you!
 
Well I changed my settings, but nothing changed at all. When it loses sync, it has a sync lost reason of 23 which comes up as 420a long tooth not found.
 
Post your revised MSQ file and a tooth and/or composite log of the problem as it occurs.
 
VelocitàPaola;152767322 said:
Post your revised MSQ file and a tooth and/or composite log of the problem as it occurs.
Click to expand...

Here's a log

FileSwap.com : 2011-10-24_14.58.28.msl download free

Here's my tune:

FileSwap.com : CurrentTune (1).msq download free

In this log you can see the rpm's randomly drop to zero throughout the log. I can't figure out why this is happening. If you go to and spot where it drops to zero, it also shows that it loses sync. It also shows the lost sync reason as number 23 which is 420a long tooth not found. Example is record 1939.
 
check your spark plug gap.. i had the same issue when i was over 5K.. i would blow out spark, cause a misfire ( it would register lean on MLV). does it do it in idle? just driving in and out of boost? if ase is kick on , thats deff a reset. i haven't looked at ## MLV yet. il try to tonight/
 
glowryder said:
check your spark plug gap.. i had the same issue when i was over 5K.. i would blow out spark, cause a misfire ( it would register lean on MLV). does it do it in idle? just driving in and out of boost? if ase is kick on , thats deff a reset. i haven't looked at ## MLV yet. il try to tonight/
Click to expand...

I just changed the plugs yesterday to new NGK BKR7E's gapped at .028 so that's not the issue. It does this at idle or any rpm really.
 
good plugs..

Are you using the cam sensor at all (idk if your running sequential/semi)? if so, check it, i had this happen when i bent a pin. it would make intermittent contact. try the same with the crank signal. In the MLV, is it spiking to 0 rpm? if so, that tells me its crank/cam sensor.
 
glowryder said:
good plugs..

Are you using the cam sensor at all (idk if your running sequential/semi)? if so, check it, i had this happen when i bent a pin. it would make intermittent contact. try the same with the crank signal. In the MLV, is it spiking to 0 rpm? if so, that tells me its crank/cam sensor.
Click to expand...

No cam sensor, and yes it spikes to 0 rpm with a sync loss error of reason 32. You'll see it when you look at the log.
 
glowryder said:
Are you using the cam sensor at all (idk if your running sequential/semi)? if so, check it, i had this happen when i bent a pin. it would make intermittent contact. try the same with the crank signal. In the MLV, is it spiking to 0 rpm? if so, that tells me its crank/cam sensor.
Click to expand...
Again, a tooth/composite log would help confirm this...
 
VelocitàPaola;152768215 said:
Like glowryder suspected, it looks like the signal is completely missing at some points. I'd check the wiring at the crankshaft angle sensor.
Click to expand...

I believe I figured it out, just drove for 20 mins and didn't lose sync once. After all that rewiring, checking connections, and changing settings...

I changed the sensor. Boom no losing sync. :ohdamn: Guess I figured a brand new sensor wouldn't be bad.

I'll report back if anything changes. Onto tuning this beast now.

EDIT...

I actually found small nicking on the sensor I pulled out.
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