hi guys.
just installed the megasquirt yesterday, and the car is running great.
thanks very much for all the posts, they are a HUGE help.

I have followed this diagram



with 2 exceptions.
The first one wasn't hard. you have to connect the 2K(LG/W) to pin26 on the MS. this gives 5v to the TPS for it to work.

The other one is the on that I'm stuck with ....
from the diagram you have co connect 1B with 2I with a 1k resistor for the tach to work. The thing is .... it still doesn't work ....

Do I have to build a Tach output circuit in the MS and connect it?
Which one ?

what pin should I connect it to ? 2I ?

thanks again guys

 

the subject might be confusing ....
the car has RPM signal and the engine starts and works.
the tachometer on the dash is the one that doesn't work

 

try it in the diagnostics box.

IG- to B+

 

what do you mean ? put the 1k resistor in the diagnostic box beetween those 2 pins ?

 

just did what i mentioned on the last post and nothing :( it still doesn't work ...

 

do you have a 95.5 model?

 

the first registration date is 07/94
It does say NA95 on the engine bay.
The car is European.

 

I have a 1k resistor soldered on the 2I ...
Just noticed that when I put 12v on the resistor leg the tach moves....
If I do on/off/on/off very fast ( the fastest I can ) I manage to get the tacho to read just above 1k rpm...
This means I need to put the MS to feed it with a 12v square wave right ?



this schematic should be enough right ?

 

yep that is what i was going to suggest. 1K resistors.

 

ok , I will try that once I find a 2N2222A
thanks

another "lame" question
I bought a wiring harness from DIYautotune.
It has the IAC spare wires but it doesn't have the SPR1-4 pin3 to 6.
The db-37 is crimped......
how can I add wires to pin3-6 ?

 

go through one of the spare IACs.

 

they are already used.
one for the second ignitor, one for boost control, another one for the idle valve and another one for fan control

 

just found a away.... wrecked an old db-9 and managed to use the contacts sucessfully.
thanks again for all

 

it's working
thanks a lot for all guys ....

PS : it's not very accurate though .... if MS is saying 5800 the dash tach is saying 6200 ... quite an error ....

 

its the dash that is in error.