Ben & I resolved the issue (hopefully) over the phone, but for the benefit of the community:

Sounds like R7 on the main board is directly related to the coolant temp sensor. So I'd assume that R6 on the main board has to do with the voltage problem.


Good news/bad news

Good: We know what the problem is & Your TPS seems to be working
Bad: You have to replace R6 & R7 on the main board

I read the TPS mod instructions again, and don't see any mention of which board gets the resistors pulled. But I remember from mine, those resistors get pulled off the daughterboard (the smaller of the 2).

So let this be a warning to others who do the TPS mod on their 9093 MSPNP (which should be everyone, especially everyone with a/c, IMO of course). All TPS mods are on the daughterboard. Do not touch the main board.

Next time Jerry/DIY-Autotune opens my PNP, I'll take pictures of the mod procedure.

 

Nice to hear that everything was solved but on a funnier note: "Ben & I" So you and yourself on the phone solved the problem sweet.. lol

 

Im still looking for a stupid TPS that will easily work aka 90-93 auto one... But i dont wanna pay the like 100 bucks people at mnet are asking.

 

I'm using one from an EH automatic transimission BMW from the mid-late 80s, Bosch #0-280-120-402. It's a 6-pin connector. I've also heard that 0-280-120-406 works, as well. It bolts up perfectly, so all that is left is to work out some wiring.

 

1st, congrats on figuring out the problem. 2nd: do both of the BMS TPS's you list above bolt straight up to the manual Miata TB, or just the one you're using?

Cheers!

Jeff

 

Both should bolt straight up, but I haven't seen the 406 in person.

 

Thanks! Much appreciated.

PS: from the megasquirt.info site, for people searching in future, here's a pic of the main board, showing the R6 and R7 resistors. As stated above, the R7 resistor is related to CLT, and the R6 appears to be related to the boot-loader circuit:



Cheers!

Jeff

 

Sorry about the confusion. You need to remove R7 and R6 on the daughter board, and leave the main board alone. I will update the documentation ASAP to clarify this. I'm glad you got this straightened out.

 

Straightened out, but not sure how I'll get those mainboard resistors back on

 

Big thanks go to Matt Cramer for fixing up my MSPNP. Now with the CLT and MS voltmeter working, I could safely take the car for a drive with the TPS working. Boy, what a difference! No stalls, not even with the A/C! There were a couple low dips with the A/C on, but there is plenty of room for tweaking the closed loop idle control settings to smooth it out a bit. All this with a Fidanza flywheel, which was causing the stock ECU to get pretty close to stalling when coming to an idle sometimes. Without A/C on, coming down to idle is great!

Now, if only I could shroud the radiator and get a working BOV...

 

<-- ******* chopped liver


J/K glad it's resolved.

One of these days I'm going to bust out the a/c wiring schematic, poke around with the dmm, and build a soft start circuit for the compressor clutch. IMO, the car should have one from the factory. But hey, they got to save $.75.

 

Thanks for Matt for sorting this out while I was out on the salt... the manual is updated now and we'll get a pic in there as well ASAP...