Miata with megasquirt problems

I do not have a megastim.

I took it apart the other day to check the physical appearance of the MAP sensor, it is not held in with screws or anything, just the soldered legs on the board. All the solder joints appeared to be good.

It makes it more difficult that I got this MS used and never had it running an engine before I did the swap.

Braindump:

What kind of wideband do you have? If you have the LC-1, it will output NOTHING (Megatune/Tunerstudio will read 8:1 or some other nonsense) until the sensor warms up, and then it will provide a proper reading. There is no in-between. This takes about three or four seconds, a time where you really shouldn't be concerned about the fuelling other than "does it run without lean stumbles?".

If you have the LC-1, do NOT let it get power unless it has a ground! Also do not ever run the engine with the sensor installed and not connected to a functioning controller.

The MAP sensor sounds... strange. It should never read anything but atmpospheric pressure with the engine off - this is about 94-95kpa where we live. Recheck your grounds. I like to ground all sensors and the computer at the same point on the engine. I call it "ground central station". Eliminates a lot of problems. 90% of the MS problems I've seen were poor grounding.

You don't have a checkvalve or anything in the MAP line, do you?

My strategy for a first cut for getting the idle right is to get the thing running, first and foremost, and keep tweaking the VE table in the idle zone just to keep it running until the engine is at full operating temperature. Yes, you're going to have to nursemaid it a lot. But, the way I've figured it, you can't begin to adjust cold enrichment until the VE map is roughed in.

Make sure the car does not try to enter closed loop. Set the step size to zero, this locks it out.

I got the new MAP sensor in from DIYautotune today (ordered Friday, that was fast) and it fixed it. Started right up, set the bast timing and messed with the required fuel settings to get it idling around 14.7-9 and set the base timing.

Tomorrow I will work on the fuel map a bit more and hopefully go for a short drive.

Maybe I pretty much have a "ground central station", everything is grounded at the same point on the block except for the main strap behind the exhaust manifold.

As for wideband, I have the MTX-L, it is working fine now except for the readings in megatune, I think I have it set for the wrong type of wideband controller so I will have to check those settings.

I have the PNP megasquirt, based on the MegaSquirt 1. I am just using the base map from the megasquirtpnp site for now.

The download section for the MS2 PNP might have a base map you could use:

http://megasquirtpnp.com/

Good to hear.