MoTeC Global Forum

Does anyone have a startup map for an LS1 they would be willing to share? The ECU is the MLS, but as it is a cutdown M4 I imagine an M4 one would do the job.

I've tried changing the LS2 map that comes with the software. Having been over the wiring many times I am hoping it is a setting I am missing as it all looks fine. Nothing is giving an error.

Running diagnostics the injectors and coils fire. When cranking the coils and injectors are both firing. I am seeing an rpm value of 120-150 during cranking so this is looks OK, TPS, MAP, water and air temps all are as expected.

The engine has all factory sensors and is using a stripped down factory loom - we've just put short extensions onto the wires so that they can plug into the Motec - full rewiring to follow once it is working.
We have the Cam and Crank sensors both going in as hall sensors on the pins 5 and 7
rfSn=1
SYSn=1
rEF=233
crip=455

A startup map would be great if anyone can help - I'd just like to know for sure whether it is a setting or some wiring issue I am missing. The engine has heads, cam, etc. so I'll be manually transferring my map for it over from the factory ECU once I get it running.

The injectors are factory bored out to 42lb, which IIRC is just under 440cc

Base fuel pressure is 56-58psi. Have also tried 30, 40, 50, 60, 70 & 80psi.

Coils are factory as are the TPS, MAP, Air Temp, Water Temp, Crank and Cam sensors. Crank and cam sensors we cannot test, but the values shown by the others are correct. And there are no errors coming up in the diagnostics page.

Being an MLS it is wasted spark with 4 injector drivers. As such both coils and injectors have been wire up in pairs
Injectors paired 1+8,7+2,6+5, 4+3
Coils Paired 1+6, 8+5, 7+4, 2+3
These are wired as above on outputs 1,2 ,3 4 sequentially
I have zeroed out the firing orders so it should run sequentially on the outputs.

The engine should startup on any LS1 base map, but mods: underdrive pulley, heads, mildish cam, ported Fast intake malifold, 90mm throttle body, 3.5"intake, 3.5"exhaust, no emissions, no power steering, no aircon.

Fuel pump, etc. all wired separately so no outputs from Motec used - it is purely to drive the engine.

Cam & crank set to hall, crank output wired to pins 5 and 7, cam to 19.... which came from drawing T24 but not sure if this is right.

WHat is the actual problem you are having? Is it just the tuning or are you having a problem getting the engine running?

Still having problems getting it running....

Have since rewired the whole car with better grade cable... managed to get it running for about 30 secs or so, seemed relatively happy then it stalled and hasn't started since.

Some further info seen as it is my car:

When cranking: No Sync Error
Crank RPM: 100-110
With either cam or crank plugged into pin 19 can see dig1 value changing between 1 and 0, so signal received from both sensors.

The following link is to a Word document I have created showing how it is hooked up, firing order and general settings. Info Document

The car has started twice, seemingly at random - have tried hundreds of times with almost every possible combination of settings. The details in the link are from the map it started on.

It previously ran fine on the factory PCM, alas I hacked that loom apart to hook the Motec up so cannot go back to it.

Both injector and ignition tests work as expected.

It does appear to sometimes combust at the wrong time during cranking - has blown the MAP sensor out and managed very loud bangs out the exhaust.

Any input appreciated as the ECU is currently little more than an expensive paperweight.

The scope output :




Look OK? I don't have a known good LS1 graph to compare it against.

Anyone know what Digital Input 1 (under Input/Output Functions) should be set to?

It is currently set to Off, even though it is the cam signal input. The help file doesn't really live up to its title by saying it should be 19, except for on the M4 (of which the MLS is a subset), and it wont let me enter 19 anyway.

It finally runs:

Both Sync & Ref sensors should be set as Hall
The wiring then goes to pins 5 & 7.

The T24 diagram is therefore wrong on two accounts. Will update the Word document, print it to PDF and stick it along with my LS1 startup map (standard coils, injectors, sensors & fuel pressure) on the internet to try to ensure no one else has to go through this.

Connecting the ref sensor to the two hall inputs means that you have 2 pullup resistors in parallel hanging off the sensor output, this may exceed its current sinking specs.

The drawing uses the magnetic input with the trigger levels set to HALL. This way only one pullup resistor is in the circuit.