Sudden sync loss

Moderator: Tom Notch

Post Reply
S_Mitchell
Posts: 34
Joined: Sat Dec 12, 2009 5:43 am

Sudden sync loss

Post by S_Mitchell » Tue Jan 02, 2018 11:42 am

I've been running spark only for the last 5 years with no issues. Last week my engine started running rough and wouldn't crank after it died. I put the stock distributor back on it to get home and run some diagnostics. For some reason I'm not getting much signal from my VR sensor below 1000 RPM, so the coils will not fire to start the car. Also I get a sync loss around 3000RPM, but it is fine above that and below it to 1000. I haven't fooled with this thing in 5 years because it ran so good, now I'm like a noob again.

My set up is MS1V3 direct firing a wasted spark coil pack. A few weeks ago I somehow cut a spark plug wire and ran a while before I figured it out (happened immediately after getting fuel and thought it was a fuel problem). It may be coincidence or could have damaged something from arcing on the engine?

User avatar
ps2375
Posts: 357
Joined: Mon Aug 18, 2014 10:04 am
Location: Meridian,ID

Re: Sudden sync loss

Post by ps2375 » Tue Jan 02, 2018 5:23 pm

My guess would be electrical noise. Same plugs? Different wires?

Clonebug
Posts: 3412
Joined: Fri Feb 16, 2007 12:28 am

Re: Sudden sync loss

Post by Clonebug » Wed Jan 03, 2018 9:28 am

Check your gap.....has your engine crankshaft endplay changed maybe????
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.

S_Mitchell
Posts: 34
Joined: Sat Dec 12, 2009 5:43 am

Re: Sudden sync loss

Post by S_Mitchell » Wed Jan 03, 2018 9:56 am

Spark plug wire fits the time frame of when it all happened. The stock system would be very noisy to watch on the composit tooth logger. I'll try this first. Gap is .7mm pulley set up is like this https://goo.gl/images/aGj3e5 with a bracket holding the sensor over the top. It's thick and bolted to the fuel pump studs.

S_Mitchell
Posts: 34
Joined: Sat Dec 12, 2009 5:43 am

Re: Sudden sync loss

Post by S_Mitchell » Wed Jan 03, 2018 6:05 pm

No luck today changing wires, plugs are the same I've always had. Tomorrow I'll pull the whole thing out and connect the stim.

S_Mitchell
Posts: 34
Joined: Sat Dec 12, 2009 5:43 am

Re: Sudden sync loss

Post by S_Mitchell » Thu Jan 04, 2018 11:40 am

I was fooling around with it this morning with TS attached. It's been so long that I don't even remember what the three LED's on the MS box mean. As I was trying to remember, I pulled some wires out of the way too get a better look and the relays went crazy. I kept jiggling wires and it would run fine, jiggle some more and lose sync. I tracked it to one of the VR sensor wires had come loose in the relay box, I don't know how it was running at all.

User avatar
ps2375
Posts: 357
Joined: Mon Aug 18, 2014 10:04 am
Location: Meridian,ID

Re: Sudden sync loss

Post by ps2375 » Thu Jan 04, 2018 10:12 pm

Glad that it turned out to be a simple fix.

Clonebug
Posts: 3412
Joined: Fri Feb 16, 2007 12:28 am

Re: Sudden sync loss

Post by Clonebug » Fri Jan 05, 2018 9:09 am

It really is amazing on how bullet proof these systems are.

That is the only complaint I have about the relay box is that the terminal strip will work wires loose if they aren't checked occasionally.

Fortunately I check my Buggy over and do lots of wiring changes so I check them at least 4 times a year.

Add that to your yearly maintenance program........ :wink: :wink: :lol:
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.

S_Mitchell
Posts: 34
Joined: Sat Dec 12, 2009 5:43 am

Re: Sudden sync loss

Post by S_Mitchell » Fri Jan 05, 2018 2:42 pm

IAT was also loose and I've found that one out before. Didn't give it much thought at the time because I only use it for spark right now.

Will define checking them every winter now.

User avatar
ps2375
Posts: 357
Joined: Mon Aug 18, 2014 10:04 am
Location: Meridian,ID

Re: Sudden sync loss

Post by ps2375 » Fri Jan 05, 2018 4:02 pm

For the years I ran MS on my Rabbit, I never had loose connection problems, but I never ran the b&g relay board.

Clonebug
Posts: 3412
Joined: Fri Feb 16, 2007 12:28 am

Re: Sudden sync loss

Post by Clonebug » Sat Jan 06, 2018 12:07 pm

ps2375 wrote:
Fri Jan 05, 2018 4:02 pm
For the years I ran MS on my Rabbit, I never had loose connection problems, but I never ran the b&g relay board.
The relay board has small screws and it's not easy to get a lot of torque on them.

I solder the wire ends to keep them from getting crushed so that could be a part of them working loose over time........or me forgetting to tighten them when installing....... :oops: :roll:
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.

Post Reply