Well - I just got back from a 3000 mile trek from Phoenix to Illinois & back. This was my acid test for the Megasquirt. It performed quite well - though not without some problems.
First I'll say that all these problems arose only because I switched out the stock Ignition with a Permatune CD unit before the trip. I didn't have any real time to test it prior to the trip.
My son and I set out on Sunday, but bearly made it an hour north of Phoenix before the fuel pump & MS both crapped out from the heat. Thankfully I had my PC and could connect to MS and determine that the Injectors circuits weren't firing. Also the Fuel pump was spinning, but when I pulled a hose it only trickled out onto the road.
I thank God that just as my son and I started hoofing southbound to a rest stop some miles back, a couple from Mesa stopped on the southbound side and waved us over. They even dropped us at our front door. Got the car towed back to Phoenix that afternoon.
Needless to say, the fuel pump was toast, as was the R10 resistor and the 4N25 chip in the MS coil circuitry. It took three days to locate and install the replacements, but we were back on the road Wednesday afternoon.
I had to bump the 390 Ohm R10 resistor all the way to 1.0K before it would run without getting too hot. Even at that it still was discolored and starting to break down by the time we drove 1000 miles. So in the motel in Wichita I bumped it up to a 1.5K. This worked well for the remainder of the trip to Illinois.
All would have been well for the return trip, except that I made the mistake of installing the cover on the MS, as I had been driving without it to aid cooling. I could tell the resistor was starting to crap out again as the car behaves much like one that is suffering from vapor lock. So we found a station in Oklahoma that had a seating area, plugged in the soldering iron and went to work.
My brohter (in Illinois) suggested putting two 1-watt resistors of 1.0K ohms each in place of the single 1/2-watt. Since I wasn't using the D8 diode, I decided to replace the jumper with another 1.5k 1/2-watt along with a new 1.5K 1/2-watt R10.
This worked quite well with no excessive heat - and would have seen us the rest of the way home had one the solder joints not broke loose. The weird part was that I didn't know at first whether the fuel pump had overheated and I was getting vapor lock. The new resistors still looked fine and didn't appear to be overheating. Since the solder joint was on the back - it was only because I touched them that I noticed one of them moved. But now we're stranded miles from the next rest stop. So we waited about 20 minutes to see if it would start. Nope. Then miraculously with one more crank - it started. We went about one mile and it started to cut out again. So I'm on the shoulder of the road, coasting, trying to start it. Again it starts up just long enought for us to make it to a rest stop 2 miles down the road.
So picture this. I have an extension coard running from an outlet in the men's restroom with my soldering iron plugged into it and resting on a rock. I've pulled the MS unit out to re-solder the faulty joints. My son is holding the circuit board while I'm repairing the solder joints. I'm just glad no one reported us to homeland security.
That's all it took. The rest of the trip went flawlessly - mechanically speaking anyway. Now I just have to plan on relocating the fuel pump to the front to prevent future FP overheating. This wouldn't be a problem, but since I've re-installed the AC compressor - it seems to aid in transferring too much heat to that corner of the engine bay.
All in all a fun little adventure.
Enjoy!