MS2 on my 2002
 

I got it to run today after several attempts at the input circuit. Like I said in a previous post, I used an LM339 instead of TL082, which worked just the same. I'm using all the stock sensors (Crank, Cam, TPS, IAT, CLT, Knock) minus the MAF (GM 1 bar) and baro (also GM 1 bar). It started on the first try, and idled around 900rpm (I'm currently NOT using the PWM valve) and pretty lean at 16.5:1. I managed to copy all my settings from my MS1 (priming, cranking, afterstart, warmup, accel/decel, VE, IGN, AFR, etc) so it pretty much just worked. Too bad it stalled just after I parked after a trip around the block because the battery died or I would have started tuning right away. Aparrently the NAPA voltage regulator is either not wired correctly or is not working - I will have to check it out or use Jason's circuit.

All in all, a spledid day I must say!

Jim

Sounds good. Now post every picture you have of your car. :) Your signature makes me drool.

can you post up a list of everything you ordered from diy autotune and whereever else to get this to work?

I'm sorry, but I am about to attempt to make a ms2 for my 2000, and this would really help. thanx

I'll write a detailed "howto" once everything is up and running normally.

Jim

Hi Jim,

Glad to hear you got things running with MS2, looking forward to the guide. :)

Cheers

I'm curious. What are you using for your 5 Hz GPS?

The 5H GPS is an OEM-intended module that I bought real cheap (like $40) from a friend. I had to build the power supply circuit (3.3V) and serial ports (it has two USARTs so I had to use a MAX232N to bring the TTL level lines to RS232 levels).

Jim

Great job Jim, look forward to pics and stuff, your original MSinstall ,(along with Aussie Driver) was my inspiration to go MS all those years ago! :)

Any updates? The write-up idea sounds good, bva MSII sticky is something we could really use here. I am looking into upgrading to MSII on my 97 right now, and was thinking that If I did it, I would want to do a write-up on the upgrade from MSI to MSII for NA cars.

I'm still trying to resolve the alternator issue. The NAPA regulator didn't work for me, neither did Jason's circuit. I'll build one using the microcontroller board I use for the battery light circuit (different than the one Jason suggested).

Jim

That's strange. Jason's circuit should drop right in and work well. What problem are you having with it?

It simply doesn't work. The output is not PWM, just a constant voltage level (IIRC 2.5V, the same as the TL431 ref voltage). Naturally, the output voltage sticks to 11.5V. I've gone through the built circuit a hundred times, to no result.

Jim

I've just finished building this circuit as well. Is there a way to test this it?
Should a variable voltage on the input (say 10 to 14.5V) give a variable voltage on the output? How much should I measure?
The car is still in the UK, so I can only test it on the bench right now.