General Help RPM POBLEM

[KillED]

Hi, I've Seisento SX 1.1 MPI and I'm Looking information For install a RPM... I already look at the interior grill (air condutor),there're 4 (cables)
Blue = signal
Red = positive(15)
Black = negative
Yellow = light
:bang:

and I already look too difrerent ECU for Sporting MPI and 1.1 MPI

and This is my RPM

IGR 8000 RPM...
sorry for my english, Thanx!!!:worship:

 

[fingers99]

I can't see a 4cylinder rev counter working. Maybe an 8 cylinder one, or one off a Sporting?

Does yours produce any reading on the car or just double what you'd expect?

IGR 8000 rpm I don't understand.

The ECU is the same for all MPI 1108s, by the way.

Where are you from?

 

[cojones]

It's got a cyl selector, among the options is 8.

Problem is, as far as I can remember from other rev counter threads, the Sporting has got a different ECU, which gives the rev counter signal (on MPI cars).

(Hi EvilD )

As far as I know with a rev counter like this you need to feed signal from one of them coil packs, am I right?

 

[KillED]

I am Spanish and IGR 8000 rpm is the rev counter of picture

 

[fingers99]

Using the ECU to run the rev counter directly would be pretty wierd, even by FIAT standards. I'm pretty sure the ECU is identical. The connections to the rev counter connector block are

red
black
yellow/red
blue

just as KILLed found.

So, what's the problem? What's happening out there?

 

[cojones]

AFAIK the wiring for the rev counter ends up on pin 23 on the ECU for the signal on the MPI car, but I believe there are different ECU modles for S/SX/Van/Sporting:
https://www.fiatforum.com/cinquecento-seicento/122633-sei-sporting-s-differences.html?p=1280890

might very well be wrong... can't find the ECU on EPER to check part numbers...

I found this, for a Panda I believe:
https://www.fiatforum.com/panda-classic/139470-rev-counter-problem-solved.html

 

[fingers99]

Interesting (in a wierd sort of way!). I'll investigate (I have a Sporting SPI rev counter to fit in an S Sei!).

But, hang on a moment, let's not loose focus. KillED is trying to fit an aftermarket rev counter. Why not forget the ECU and the FIAT wiring altogether and take the pulse from one of the coils, the Crank or Cam sensor? Somewhere there's a Guide or a FAQ where someone has fitted a rev counter to an 889: that would be a good place to start.

Looking through FF ePer I get "error on page": should show me 4 schematics, shows me nothing. :bang:

 

[cojones]

Yes please, indirectly I'm interested too as I want to fit one on my SX as well would you reckon a setup like this Panda guy would work?

 

[fingers99]

Yeah. but with a switcheable one I can't see all the diode stuff being necessary.

 

[randomizered]

Pretty much all modern cars rev counters are drivven by the ecu. It makes sense really, they are checking rpm anyway, and can provide smoothing, etc to gauge, to make it morestable and less worrying to the user . Also factor in lots modern cars have no HT leads and the coils are deep in the engine ( coil on plug )

@Killed - why not just fit a sei mpi rpm gauge, it'll be a direct fit then You can alwya put the gubbins in a different housing.

The signal is PWM signal i think, no good for those that trigger off an inductive spark output. You will need to run new wiring to the bay. Of course you can use all the other lines apart form the signal line to power the thing