AZOutlaw

It's very likely a communist plot. I am close to Sedona though and we get some of that Vortex activity and Harmonic Convergence over here too!! That's the only way to explain the end of my flight. My landing was 14100 above the runway at 183 mph

Thanks guys. I'm leaning towards an antenna issue. I updated the data card and went to the airport to see if that cleared. It did and both radios started up with good GPS. Second attempt, they did not and I got the same no GPS message. The next 5 starts resulted in GPS reception but it was really slow and seem to struggle to find the satellites. The status bars sat blank for awhile until one or two would start to show something I tried them with the 796 on and off and it didn't seem to matter. I'll get with an Avionics shop nearby, probably after the holidays, and report back. Thanks again and Happy New Year (and Happy Flying) to all.

Could not find any outages and there were none that ATC knew of during the flight.

I see some old threads on this related to antennas but nothing new. We flew 1.5 hours yesterday and while turning base to land, I got alerts that there was no GPS on either unit. When we headed home, both units would never find a GPS signal. I did a lot of restarts and all and nothing worked. I do have a yoke mounted Garmin 796, and it had GPS the whole time. This did happen for about 20 minutes back in September but they both came back and worked fine so I assumed a short GPS outage. A couple of things to note. While I recently updated the data cards and the Garmin website said they were good, the 430 seemed to have an issue as it said it was referencing true north. As we were flying along and I was looking for issues I did see one note on the 430....Not receiving input data on 232 channel #3. The manual just says it's not getting that data, but not what data it is. Any thoughts?

Yes it was Bruce and I agree, he's great! I took the left mag to him yesterday and he tested it out. It appears we got a bad capacitor. He put it on a tester and we could see intermittent sparks. Not a lot but you could sure see a few drop out. He found an old capacitor in a drawer and put that on and it cleared things up. He didn't have a new part to match so I'll get it back next week and update the results.

Thanks guys, just a refresher. It's a brand new harness two weeks ago and it was tested, for good measure, last week. Mags were rebuilt this summer and only have 6 hours on them. I'm very familiar with burning off fouling and have done that numerous times. Timing has been checked and re-checked. Fuel injectors were removed and cleaned. I'm leaning towards the fact that my Magneto rebuild didn't get rebuilt properly. We pulled them out and sent them in when this started after first replacing the spark plugs. The problem was there before the rebuild and remains still.

Update: Bottom line, the problem still exists. We checked the timing and did think it was off a little so we adjusted that. Fired it up and first check had the same result. (-150 Left and -40 Right) We shut it down, discussed a few things and decided to try again. This time it was perfect, about a -35 mag drop on each side, or what it always did in the past. Took it up and all seemed good. In flight mag checks were equal and uneventful. Landed and did a check before shut down and got a -65 on the left. Went back a day later and got the same (-150 Left and -40 Right). Borrowed a different timing box, bumped them slightly and felt they were perfect, same result and this time the inflight test was bad on the left, like it was a week ago. Swapped bottom and top plugs thinking the issue might move to the other mag. It did not. Same result, but what is interesting is I did the second start up 30 seconds after shutting down as before, and got perfect mag drops again. This got me thinking heat and resistance was an issue. Pulled all the plugs and did a resistance test, twice, and got these readings. Seems that 5B is reading low and 3B is high but all the rest are really close. I found this online. "Champion Spark Plug Company’s Engineering Manual gives the nominal value for their resistor type of aviation spark plugs as 1000 - 1500 ohms" Anyone have real world experience on what is good and bad readings for a Champion plug?

Thank you and that's where we are headed. Just wondering if there is a better way to time a Mooney than with an antiquated sundial attached to the spinner? Surely technology has caught up to that too.

Here's some info I got today. The Left mag side is definitely hotter. I did the inflight mag check as well. At first I ran it out to LOP and it was in the high 1400's. When I did the Left check, everything immediately went off the scale. The ships single EGT gauge went way past redline so I quickly backed out of that. I went richer with the mixture and got a lower base EGT and ran the same check. The right side was smooth and normal. All EGTS rose some but nothing drastic and the engine was still smooth. The Left EGTs took off in different directions and the engine got rough. I had video and at the bottom is a screen shot just before the mag check, the second screen shot is 4 seconds after turning the key.

Everything leads to timing I guess. It started in JAN and we changed the plugs. We then sent the MAGS out for rebuild and after a lot of delays got them back and installed with the same result. After that is was the injector clean out and then yesterday, a new wiring harness. Waiting for the rain to clear out and then I plan to test it more today while watching EGT's closer.

Probably 8 hours on the plugs. 25 minutes on the wires and the clean injectors. 6 hours on the rebuilt mags. Plugs are Champion RHB32E, massive and yes, we checked resistance. I honestly can't remember if he checked them all though.

I have these and they both tell me the same thing.

Thank you Marc, I have a JPI EDM 800 but I can look at the EGT's closer tomorrow. I thought I would put bottom plugs on top too, and tops to bottom, and see if the problem switched to the R mag.....then it's a bad plug.

Thanks Hank, but I have brand new wiring as of today. I think they're good.

It started before the mags were serviced.