Spark being blown out?

[PSmurf78]

Hey guys, I think I'm having an issue with loss of spark under boost and load.

Current setup is:
MS2 V2.2 board
V2.34 (I think) code
With EDIS for ignition

Engine:
Turbo 4A-GE

What I'm noticing is when I'm pulling from about 3K-8K, there will be little hesitations. They're inconsistant at which RPM's. I've changed out the OEM coilpack for an Accel EDIS coil pack, which helped but still might feel like 2-3 misses during a pull. I've narrowed the gap on the plugs and they're one heat range colder then stock. Advance under boost is about 20 degrees all the way to 8K.

What has me really nervous is right now I'm only boosting to around 5-6PSI. The engine was built for 20. After I get 1K miles on the engine, I wanted to go up to 12 PSI, but I've gotta fix this issue.

What other options are there to get a stronger spark. I've been told by 2-3 people now that it feels like the spark is being blown out. Are there additional tricks I can try to get the spark stonger?

[PSIG]

... What I'm noticing is when I'm pulling from about 3K-8K, there will be little hesitations. They're inconsistant at which RPM's. I've changed out the OEM coilpack for an Accel EDIS coil pack, which helped but still might feel like 2-3 misses during a pull. ...

I would diagnose this with a log of the event. Do you have one to send? Check your logs and look for signal noise. Reroute and/or shield if so. Also, I'd reduce boost or wire the wastegate open for zero boost to diagnose and do a pull. If it still hesitates it's not the spark getting blown out. Just some ideas to narrow the issue down.

[PSmurf78]

I could try reducing boost, but it's only at 5 PSI right now. All the lines are to MS, to the CAS, etc. are shielded.

What would noise actually look like in the logs? I don't see any massive spikes in RPM's during a pull. Typically it's a very linear pull with just a small hiccup then it resumes the pull.

[PSIG]

I could try reducing boost, but it's only at 5 PSI right now.

My point exactly. It is unlikely that your spark is being suppressed at only 5psig. Dropping the boost to zero would prove that or not and it's easy to verify. Usually when sparks get suppressed they avalanche with a small increase or decrease in boost causing a large increase or decrease in frequency.

In the logs you're looking for anomalies. Check all the the traces for noise (jitters, twitches, spikes) especially your timing traces. Your EGO trace should show lean if you misfire - verify that. What are the other traces doing at that point? Your pulsewidth will twitch if it's a fuel issue or in response to the lean spot if correction was on. You get the idea.

There are many other clues that are in the logs. Sit down with your favorite drink and stare at them until you find the evidence of the 'hiccup'. Then you can compare all available traces (only a few are shown at a time in MLV) for more clues at the event. With those clues you can suspect or eliminate causes. Did MS hiccup? Did the VR sensor go blind? Did a plug lead crossfire? Did the O2 sensor (or IAT or CLT or...) lead lose contact momentarily? Did the EDIS module skip?

Hope that helps - post a log if you have one.

David

[S.Bretz]

I was have a problem kinda like that...after see the data log in the Megalog veiwer, the problem becak real clear. The AE enrichment was too sensitve and would kick in...then the a/f would dip. The TPS and the MAP had a little noise due voltage fluctions. I relocted the power and ground right ot the battery and turn the battery lag down. the problem stopped. I also turn the AE threshold points a little higher to they would nned more 'noise' to engauge.



DL the log viewer and go over a few few pulls. The over lapped graph of whatever parameter you want to look at makes it super easy.

[PSIG]

Get Phil's newest Mega Log Viewer here: http://www.ideasandsolutions.biz/MegaLogViewer Great stuff!