Megasquirt owners thread

gslender · Postby **gslender** » Sun Jul 21, 2013 8:05 pm

If you Gnd the 5v line then the ms will go offline. The serial ports share the 5v circuit.

G

16bit · Postby **16bit** » Fri Jul 26, 2013 12:03 pm

i am in the process of planning to install a ms2v3 on my nb8a.

i will doing a maf delete using this iat sensor.

http://www.diyautotune.com/catalog/gm-o ... -p-62.html

i will be getting an innovate mtx wideband

http://www.diyautotune.com/catalog/inno ... p-467.html

I will be using rx8 injectors.

at a later stage i will try to install cops.

is the stock tps on an nb8a going to be fine to use or do I need to upgrade. if so what tps have people had success with?

timk · Postby **timk** » Fri Jul 26, 2013 1:55 pm

OE TPS is fine.

16bit · Postby **16bit** » Fri Jul 26, 2013 2:00 pm

excellent.

16bit · Postby **16bit** » Fri Jul 26, 2013 2:16 pm

need a tuning laptop, thinking of one of these.

http://www.reboot-it.com.au/dell-latitu ... aptop.html

looks cheap

sailaholic · Postby **sailaholic** » Fri Jul 26, 2013 4:13 pm

I've found backlit keys to be very handy for night time tuning of you can find a equipped laptop that is reasonably priced

Sent from my GT-I9100 using Tapatalk 2

gslender · Postby **gslender** » Fri Jul 26, 2013 7:04 pm

16bit wrote:i will be getting an innovate mtx wideband

Folks should avoid the MTX-L wideband controller. It sux when used with an ECU as you will struggle to get the ECU and built-in controller/gauge to agree on the readings due to them having completely separate GNDs. There is little you can do other than artificially set the ECU to match (by eye) the controller/gauge.

A better solution (and what I recommend) is the LC1 kit with gauge - it is better as it has the controller separate and allows the gnd to be at the ECU and shared with the gauge (assuming you correctly wire it that way).

http://www.innovatemotorsports.com/xcar ... ctid=16291

G

16bit · Postby **16bit** » Fri Jul 26, 2013 10:26 pm

thankyou sir.

16bit · Postby **16bit** » Fri Aug 02, 2013 11:25 am

hello all.

just wanted to confirm that these are the two items i need for the iat.

here is the sensor.

http://www.bmotorsports.com/shop/produc ... cts_id/400

and here is the pigtail.

http://www.bmotorsports.com/shop/produc ... cts_id/409

gslender · Postby **gslender** » Sun Aug 04, 2013 6:54 pm

Looks a out right. DIY Autotune sell em in a pack with a bung (and I can supply them too)

G

16bit · Postby **16bit** » Mon Aug 05, 2013 2:50 pm

bought em. diy had postage at 38 bucks.

Mr nanotech · Postby **Mr nanotech** » Tue Aug 06, 2013 10:21 pm

Ok so I have a problem and I'm not sure what could be causing it. Basically, my car is running on diypnp2 with a gm IAT and LC1 wideband, using MAP. Had a lot of trouble initially but finally got the car to idle at a steady 14AFR. It's on the rich side but It's better than lean. 550cc injectors too.
I'm tuning it n/a before putting the supercharger on.

Right now I've been having some interesting issues. When you stab the throttle (blip it with the pedal), the afr goes pretty rich; approximately 10-12 on the afr gauge depending on revs. However on slow steady depression of the throttle, the car leans out. between 1000-2000rpm, it goes from 14 on my afr to about 16. Anything about 2500rpm the afr hits a whopping 19.
I don't want to detonate my motor or anything so I need some advice.

After going through setting after setting making sure this and that was set up and calibrated properly, I put it into autotune mode. Sure enough it fixed some issues. I decided to test to see how the afr changes under engine load. So I slowly drove the car up and down the driveway to see if there was a substantial change. Well to my surprise it seemed to stop leaning out both on slow steady throttle and sharp blips. I figured things were on the mend. Getting out of my car to take a couple of photo's (since today is the first time it's been out the garage in months), I noticed the exhaust note changing like it was about to stall. I got in the car to see the afr at idle had hit 19 for some reason. I put the car in the garage but on the way it felt like it was starving for fuel, like it was grazing an empty tank (has 3/4 full tank of fuel). Not sure what the hell is going on and need some advice and places to look.

My plan tomorrow is to recalibrate the wideband to make sure it's not sending out a dodgey signal (do a free air test etc), make sure the cars timing matches tuner studio, go through my tune with a fine tooth comb and look for anything that looks dodgey. Short of that I'm not sure what to do.

Postby **NitroDann** » Tue Aug 06, 2013 10:37 pm

Google how to tune accell enrichment.

Do more auto tune.

And yes calibrate the wide band again.

Dann

Mr nanotech · Postby **Mr nanotech** » Tue Aug 06, 2013 10:44 pm

Thanks. I've put the battery on charge for the night and I'll attack it again tomorrow.

gslender · Postby **gslender** » Wed Aug 07, 2013 9:14 pm

Mr nanotech wrote:... but finally got the car to idle at a steady 14AFR. It's on the rich side but It's better than lean.

That's actually fairly lean for idle - you should target 13.5 for idle as most engines like to run a little rich to ensure it is smooth. If you run it leaner it will increase chance of running rough. Rich plus plenty of advance (12-18 deg) usually results in a stable and steady idle.

Mr nanotech wrote:550cc injectors too.

Make sure you have the dead times correct as this will impact idle.

Mr nanotech wrote:Right now I've been having some interesting issues. When you stab the throttle (blip it with the pedal), the afr goes pretty rich; approximately 10-12 on the afr gauge depending on revs. However on slow steady depression of the throttle, the car leans out. between 1000-2000rpm, it goes from 14 on my afr to about 16. Anything about 2500rpm the afr hits a whopping 19. I don't want to detonate my motor or anything so I need some advice.

You can't pre-detonate an engine (ping) when there is no load - so don't be too concerned about that when free reving. I'd follow Dann's advice and autotune free reving as much as possible ensuring the engine is hitting as much of the rev range as you can. You will struggle to get the higher Kpa without going for a drive, but you might hit a few when doing WOT.

Mr nanotech wrote:After going through setting after setting making sure this and that was set up and calibrated properly, I put it into autotune mode. Sure enough it fixed some issues. I decided to test to see how the afr changes under engine load. So I slowly drove the car up and down the driveway to see if there was a substantial change. Well to my surprise it seemed to stop leaning out both on slow steady throttle and sharp blips. I figured things were on the mend. Getting out of my car to take a couple of photo's (since today is the first time it's been out the garage in months), I noticed the exhaust note changing like it was about to stall. I got in the car to see the afr at idle had hit 19 for some reason. I put the car in the garage but on the way it felt like it was starving for fuel, like it was grazing an empty tank (has 3/4 full tank of fuel). Not sure what the hell is going on and need some advice and places to look.

My plan tomorrow is to recalibrate the wideband to make sure it's not sending out a dodgey signal (do a free air test etc), make sure the cars timing matches tuner studio, go through my tune with a fine tooth comb and look for anything that looks dodgey. Short of that I'm not sure what to do.

If you send me a log of the tune and the tune itself I will happily give you some advice on what I think might be the issues. But ensuring you have the WB correct and using autotune with correct timing and you should be fine. I'd be checking those deadtimes for the injectors.

G