MoTeC Global Forum

After over a year of service I have developed a "Error Sync Signal" with an occasional "Error Over RPM". Curious as to where I need to start looking for problems. I am assuming a bad Coil Pack or a bad Hall sensor. Any where else I should be looking?

Hi,

I would start with doing a Ref Sync Capture and seeing what the signal looks like. If you have a Ref Sync Capture from when the engine was running without the errors, it would be good to be able to compare them as well.

I am attaching 2 files. the requested RSC file, and the Logged Data file.

Time breakdown for the Logged Data file:

Aug 20th

0:00 - 5:00 - Staging
5:00 - 13:40 - On Track
13:40 - 15:00 - Pit In
15:00 - 19:40 - Head Scratching and Load on Trailer

Sep 3rd

19:40 - End - Start in Trailer, More head scratching

Please note the Error Over Rev starting at 10:20 and the Error Sync Signal starting at 14:40. I charted these vs RPM to check the over revs.

It is not allowing me to upload a RSC2 file extension.

First thing to check is the connector for the sync sensor, look for signs of fretting on the pins or dust inside the connector....

However having looked at the data I get the idea there's bigger problems going on. I would say it doesn't look to me like the alternator is charging the battery. The crazy spikes in all the sensor channels, have you had them before? I have seen something similar once with a dash where there was a fault in the main power supply relay, so maybe check the alternator, the power switching and the battery.

From a diagnostic point of view I would suggest increasing the log rate on the error groups , 1 hz is not sufficient when trying to diagnose problems.

I see what you mean about the voltage spikes. The battery is an Optima Red Top and is less than 6 months old (thought the battery acted as a buffer for voltage). I also replaced the alternator last year. Could the spikes be caused by the coil pack shorting out? Or is it more likely a short in my system. I will have the battery and alternator tested the first chance I can get to eliminate it as a possibility. I went through the cam sensor and could not see anything obvious.

Also do you have a battery isolation switch, best to check that as well. Looking for bad contacts, intermittent faults.
I'm reasonably confident the alternator has failed, I'd expect to see over 13 volts if it was charging

The spikes are spikes in the data channels, possibly, but not necessarily caused by voltage spikes , trick is finding what is causing them.

What I have found:

1) Alternator and battery are good
2) Alternator tensioner was broken, I am assuming this resulted in poor alternator performance
3) My ref and sync sensors are located on my cam gear. I had a replacement screw holding the cam gear cover in place that was rubbing on the cam gear, resulting with iron filings on my magnets.
4) Connections were good, sensors appear good.
5) In the process of replacing ignition cutout switch

Future
1) Plan to put it on a dyno next week.

Any helpful hints where I need to look harder. Your help so far has been greatly appreciated.

Might want to verify timing belt tension and the timing belt related parts are good.