added TPS, now no CLT or Bat. Voltage!
 

So I added a TPS using the instructions from the MSPNP manual (remove R6, R7, and add two jumpers) but now have some really weird stuff going on.

I no longer have a correct coolant temp reading. It is stuck at 170°F. And the voltmeter is stuck on something like 29.998V. Also, I have some nasty idle-hunting now. Plus, if I turn on the AC (just added a belt...it's been off since before going MS and turbo), and the car stalls coming to idle while driving, every time.

Anybody have any ideas?

https://www.miataturbo.net/forums/sh...ad.php?t=11792 read my post, it's the second one. it'll help you with the AC stall at light thing.

I'll give that a try. Thanks.

:scratches head:
sorry man. Jerry said he was going out of town. Hopefully Matt Cramer will check the forum soon.

At least does the TPS work?

One thing I just thought of about the CLT which is odd...the fan turns on...but that's set for 175°F...?

I checked a quick datalog to see if maybe MegaTune was just being wonky with displaying the CLT, but the log had 170°F constant.

Ok, this is weird also. When I open a subwindow in MegaTune, the gauge freeze-frame shows CLT accurately.

I can't get the idle sorted. It's WORSE with the TPS!

2 things
1> Did you restart your laptop?
2> Idle settings need to get tweaked.

I'm fucking bored as shit, at home alone on a Saturday night. Let's fix the muther.
B

PS, #1 is rhetorical.

Haha

My idle AFRs are jumping all over the place.

I'll give you a call after dinner with the wife

Ok, this CLT issue is bad, real bad.

I hooked the Palm into the MS to see if it gave the same readings for CLT and BatVolt that MegaTune did (170°F and 29.88V), and the PalmTune showed CLT of 1017°F and BatVolt of 29.88V, which explains why the fan is now on constantly (1014>175).

Also, cold cranks aren't very fun when the MS isn't triggering cold-start enrichments, even when ambient is 90°F.

So anybody have an idea as to what I screwed up?

Question is when you open up the megasquirts, did you cross a wire or did solder make a connection it shouldn't have.

You realize you have to set up the Palm software to match your sensors. Make sure you read through PalmLogs site (http://www.blessedmemories.net/Palm/PalmLog.htm) and change the resistance values to match the stock sensors (you will have to use EasyTherm to get the correct values). As far as your battery voltage goes, can't really offer any assistance there.

Check my thread for the wrong collant temp. Your CLT is wrong because you removed either r4 or r7. I forget which one is the resistor for coolant but you need that in for the CLT to read correctly. I will put money on thats what is wrong.

I am wondering at also... wish I had exp with mega, cause I am just a stone throw away, from him. Where is ben...lol

Yeah, I did that before I ever hooked up the Palm. Palm had been reading temps just fine previously.

Interesting...the MSPNP manual instructs to remove R7 for the TPS mod...

R7 gets burned off when you do the TPS mod. It's gone on mine, and my Coolant temps sensor works right, and has since the mod was done.

You have a photo for him to look at, maybe he crossed a wire. I am really thinking something is in the wrong pin.

I actually called Ben for verification on his modded board to make sure I was wiring the correct pins. They're correct. The only thing I can think of inside the unit is some midplaced solder, but I was really careful and inspected before putting it all together and didn't see anything.

Ben did you pull R7 from the daughterboard or the main board?

Uh oh. From the main board. I didn't even see R6 or R7 on the daughter board.

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.

:hs:
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. :cool: 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:

http://www.megamanual.com/ms2/v3pcb_2.gif

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...

<-- fucking chopped liver
:hahano:

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...