gooflophaze

There's a rev limiter by gear table, I'll see if I can screenshot it.

Cujoel

I've see some other guys with a similar problem I think it has to do with the Park/Neutral into the ECU. If I remember correctly the rev limiter is set to 3600 whenever it detects a Park/Neutral signal. I'm running an auto ECU from a Camaro. I never tried actually revving it up that high when it was running (it still hasn't left the garage). My ECU seems to have died right now and I have no 5v reference signals, so I can't test that theory right now, but I thought it was something I stumbled across in one of the manuals. I'll see if I can dig that bit of info out.

gooflophaze

HP Tuners comparison function is pretty useful. But there's your limiter.

ooja3k

iTrader: (1)

Great find! Thank you. This will help future builders

Cujoel

What did you use for a park/neutral signal? 12V? Did you ever try just disconnecting that signal?

ooja3k

iTrader: (1)

ended up finding the correct manual ECU and thats all it needed.

csdilligaf

I have been collecting parts for my swap and I am not the most techy guy so I bought a new wire harness, New GM ECU that has been re-flashed with a tune and deletes needed and came with the pigtail for the pedal and the OBDII from Andrew at Keisler Automation for under $1250. Its turn key and ready to go, such a smokin' deal since I would have struggled to figure it all out. When I start my build log I will post up the results.

Cujoel

Where did you get a manual ECU? The ebay guys are clueless.

LukeG

Just spoke with V8 Roadsters today about the ECM. My donor is a 2015 auto camaro and they told me I need the GM ECM with the part number 12648906. If you search this on ebay you can get them for about $60 all day long.

Edit: ^^^ This info is wrong.

tomrev

https://www.miataturbo.net/build-thr...x-build-95543/ Here's a short thread on my NB LFX build. I didn't show the whole process, since other guy's had done a good job with that.

gooflophaze

Again, beware buying off ebay without knowing exactly what you need.

12648906 is the E39 part number - but you need to be 100% positive that you're getting one from a similar setup, as that part number also includes 4 cylinder non-LFX engines. You have a few more options since you're retaining auto.

LukeG

Shitballs, are there any other identifiers to make sure it is the proper ECM?

I'm going MV7 manual and ditching the auto.

This is the one I bought today.
https://www.ebay.com/itm/282654934414

gooflophaze

Cancel your order if you can. I'll see if I can find the post in my build thread where I talk about ECU options - https://www.miataturbo.net/build-thr...0/#post1390446 https://www.miataturbo.net/build-thr...1/#post1471054

LukeG

Damnit, pretty sure they already shipped it. I found a 2013 camaro lfx 6-speed ecm at a Texas salvage yard for $40. Car-part.com lets you sort through the engine control boxes for specific years and models and you can also see if they are from a 6-speed car.

Thanks for the pm and heads up! I guess it is off to the gun range for the ebay ecm.

I'm going to Overkill for the E85 kit and tune, so as long as it is from a 6-speed camaro lfx it should be fine.

gooflophaze

ECM selection is a real PITA - GM purposefully makes it not easy under the guise of 'security', and I had a bunch of learning to do before we got ours right. On my LS3 it was a bit easier, since you can bench flash the E38's, I paid a little bit extra and got a proper Camaro flash on mine. And even with car-part, I'd call the yard and make sure they're not substituting a part that follows a serv #. Car-part (on top of the search interface) offers that database as potential substitutions to the yards.

LukeG

Thank you and GREAT advice! I'll confirm that it is actually from that car.

Cujoel

I thought there was a bit more to this. Getting a flashable ECU was only part of the issue if it is not from a v6 camaro six speed. The ECU has to be flashed with a different VIN number. GM assigns software paramaters based off the VIN. You can get it to run with Auto tune, but the ECU won't change the torque parameters, at least that's my understanding.

I wasn't able to flash my ECU with EFI Live and I can't remember why now. I may have just been out of credits.

LukeG

If that was right then wouldn't there be no working LFX swaps? Not trying to be a smartass, just trying to understand this so I can get the right ecu.

Cujoel

They probably all have the same VIN. It's possible to reprogram, but you you're going to have to steal a VIN..You can easily do it by simply doing a search for a 15 camaro v6 six speed and stealing that VIN.. I don't know about how legal that is, but it's very easy. I'm just not sure how to Flash it. I paid a guy to flash mines, not sure if that is legal or not and I assume that's why people are staying pretty tight lipped out it. I don't know if you can do it with EFI Live or HP Tuners. I'm sure somebody else can chime in on what they did.

gooflophaze

So I may have to expand upon this further (probably in my own thread) on HPTuners and GM ECM's as a whole.

But to try and shed a little light on this without going into heavy detail - 3 things to keep in mind:

MFG PN: This is the actual GM part number. There are multiple "E39" ECM's that share the same processor but slightly different hardware - different pinouts, options, etc.
SERV #: This is the compatible-matrix of read-only software on the device that can be changed between different models - IE, an Acadia with an inline-4 shares the same Serv # as the V6 Camaro - and can be turned into a Camaro ECM provided it is flashed with GM tools inside the target vehicle. I'm oversimplifying things here, but roll with it. If you put an Acadia ECM into the Camaro, all the other canbus devices in the Camaro have to agree that this new ECM can be flashed to the new Camaro software. Since most of us don't have a working Camaro hanging around, this eliminates the option of readily changing any old ECM into a Camaro. Older ECM's can do this much easier - it's called bench flashing - and you can take any old E38 Sierra ECM and turn it into a Corvette ECM on the bench without needing an entire working car to do so.
Software Version: Due to the nature of HP Tuners / EFI live, they cannot "install" new software onto the ECM - IE, they can't copy the manualtransmission.exe from another ECM and install it onto your ECM that's already set up as an automatic - that's software piracy. They can, however, edit some of the bits that are already there - like changing your fuel tables, and disabling the vehicle anti theft system. Older ECM's already had manualtransmission.exe and automatictransmission.exe on them, and the tuner programs could edit the bits to tell the main program which to use.

So - long story short - The easiest way to make sure everything works is to get the right ECU the first time. Buying a ECM off of rockauto / ebay / GM is possible - but those are sold with the expectation they'll be reflashed with the GM software inside a working vehicle. Bench flashing is not allowed with E39/E39a ECM's. Tuner software does not add any new software - it only changes what is already on there.