Megasquirt new install issues

[andys_tvr]

Hi Guys,

I am new to this forum and to MS so please bear with us..!

I have a MS v3 and have got a few funnies going on with it.

I have connected a JimStim to the MS and attached the whol lot to a laptop. Everything seems to work ok apart from the o2 sensor which goes right off the scale and output 3 and output 4 flash rapidly and randomly...?

rpm is smooth, air temp and coolant temp are fine...

Also the injectors do not seem to fire on the car when i connect the MS.

I have got 12v at the injectors when the ignition key is in the crank and run positions but the plugs are bone dry.
The fuel pump definitley primes as well so i know it is not fuel pump related.

I did notice that q1 and q5 (fet transistors) were bolted to the heat sync with metal screws instead of nylon so i changed these...i have not tested it since but will let you know if there is any difference.

Has anyone got any pointers???

Cheers
Andy

[Matt Cramer]

Hi Guys,

I am new to this forum and to MS so please bear with us..!

I have a MS v3 and have got a few funnies going on with it.

I have connected a JimStim to the MS and attached the whol lot to a laptop. Everything seems to work ok apart from the o2 sensor which goes right off the scale and output 3 and output 4 flash rapidly and randomly...?

Ok, exactly what reading do you get?

If the outputs aren't set up to do anything, you can get that sort of effect as they're in an undefined state with some MS variants until you set them up to do something.

I have got 12v at the injectors when the ignition key is in the crank and run positions but the plugs are bone dry.
The fuel pump definitley primes as well so i know it is not fuel pump related.

Do you have RPM while cranking? Do you see injector pulse width?

I did notice that q1 and q5 (fet transistors) were bolted to the heat sync with metal screws instead of nylon so i changed these...i have not tested it since but will let you know if there is any difference.

Has anyone got any pointers???

Cheers
Andy

Differnet kits have used different hardware. These can use metal or plastic screws.

[andys_tvr]

Hi Guys,

I am new to this forum and to MS so please bear with us..!

I have a MS v3 and have got a few funnies going on with it.

I have connected a JimStim to the MS and attached the whol lot to a laptop. Everything seems to work ok apart from the o2 sensor which goes right off the scale and output 3 and output 4 flash rapidly and randomly...?

Ok, exactly what reading do you get?

If the outputs aren't set up to do anything, you can get that sort of effect as they're in an undefined state with some MS variants until you set them up to do something.

I have got 12v at the injectors when the ignition key is in the crank and run positions but the plugs are bone dry.
The fuel pump definitley primes as well so i know it is not fuel pump related.

Do you have RPM while cranking? Do you see injector pulse width?

I did notice that q1 and q5 (fet transistors) were bolted to the heat sync with metal screws instead of nylon so i changed these...i have not tested it since but will let you know if there is any difference.

Has anyone got any pointers???

Cheers
Andy

Differnet kits have used different hardware. These can use metal or plastic screws.

output 3 and 4 are not configured for anything yet so yes it could be that.

I am seeing RPM and am 90% confident pulse width was registering when i tried the other day with a laptop connected but will need to double check tonight.

i will be home in half hour so will give it a go then.

[andys_tvr]

Well i tried again last night and failed...!

I now have no rpm or pulse width.

I have adjusted the trimmer potentiometers so they are as follows 52 is at 96k resistance (turned anti-clockwise) and 52 is at 0 volts when the stim is plugged in.

Somthing is definitely amis because i had rpm at the weekend when i was trying.
Tonight i will go back through my wiring on the car and see if i have changed something or there is a lose connection somewhere.

I got a feeling i am doing something daft....!

[Matt Cramer]

Please post an MSQ and a data log of an attempted start. Also, can you get RPM on a Stim?

[andys_tvr]

Cheers Matt,

I will post a log of an attempted start this afternoon.

Good news is i have changed the map and i now have rpm and pulse when i connect to a laptop and try to start the car.
Still no joy firing it up yet.

Like i say i will post a log and .msq and see if you can make sense of what is not happening.

Cheers for the help.

Andy