Megasquirt and lambda question

DaveEFI · Post by **DaveEFI** » Fri Oct 31, 2014 2:24 pm

ISTR reading somewhere that a wideband sensor can't stand quite so hot gasses as a narrowband, so shouldn't be fitted too close to the engine?

FWIW, the heater on mine has never come on once the engine is running even with it more than a metre downstream - so I assume it's not a bad position. After all, many just stick them in the tail pipe to get an AFR if the car hasn't got one fitted.

sowen · Post by **sowen** » Fri Oct 31, 2014 9:54 pm

Yes, I do remember the instructions to fit my lambda specified a minimum distance from the engine, but on a turbocharged car it's not so much of an issue. Being it's fitted to my turbo'd car, I skipped the bit on how far! Also fitting the lambda from the inside would help a lot to keep the engine bay wiring as neat as possible.

I've started laying out the loom and seperating it into three primary legs, engine, engine ancillaries (EDIS and intake temp) and cabin (power, knock, lambda). Doing that I can leave the engine loom coiled up in the footwell until I'm ready, and have the rest of it up and running quite quickly, I hope

sowen · Post by **sowen** » Sat Nov 01, 2014 6:25 pm

My wideband lambda is now fitted

There was a handy rubber bung in the floor directly inline with it under the passenger seat so quick and easy to route into the cabin. Plan tomorrow will be to sort out the power feeds and earths for the EDIS, Megasquirt and lambda, and see if my laptop talks to the Megasquirt!

DaveEFI · Post by **DaveEFI** » Sun Nov 02, 2014 10:26 am

I dunno if you're using the basic Lucas EFI loom for the relays etc, but if you are do fit a 3 amp fuse to the +12v supply to the MS itself.

sowen · Post by **sowen** » Sun Nov 02, 2014 10:45 am

DaveEFI wrote:I dunno if you're using the basic Lucas EFI loom for the relays etc, but if you are do fit a 3 amp fuse to the +12v supply to the MS itself.

Mines originally a carb model so no existing efi loom to mess about with. I'm using a redundant relay socket in the main relay board for the power supply, using a bunch of inline fuse holders to the various additional looms so it is completely seperate from the original car loom.

I might make a hinged tray above the glovebox to hold the MS ecu and associated relays and fuses when it becomes more finalised. The plan now is to get it running before cutting the looms back incase I change my mind and decide to mount the ecu somewhere else?

sowen · Post by **sowen** » Sun Nov 02, 2014 5:31 pm

Success!

The wideband lambda is now showing on my computer hooked up to the MS ecu, helped once I unlocked the afr calibration settings!

Next problem is getting the EDIS to communicate with the MS, engine runs on the EDIS, but the TunerStudio shows not rpm synced, I'm guessing there's a setting somewhere that will need changing, I hope!

DaveEFI · Post by **DaveEFI** » Sun Nov 02, 2014 7:04 pm

Is it still running on carbs but with EDIS? Unless MS sees a tach signal from EDIS, it won't inject.

Was your MS unit supplied ready for EDIS?

sowen · Post by **sowen** » Sun Nov 02, 2014 7:20 pm

It's hotwire efi, the dizzy and coil are still in place to trigger the hotwire and tacho, and the EDIS is running as it's now got the coilpacks mounted on the side of the plenum. I simply am not getting a reading on my computer of any rpm signal.

The MS is only sat on the passenger seat powered up and reading the afr. I intend to run it spark only while I get to grips with the system and interface before moving onto fueling, one step at a time keeping the car on the road as much as possible.