Hi all

Had a map sensor issue with my cinq, got it replaced and all sorted

However the EML now comes back on whenever i hit full throttle! No drive ability issues now.

IAW scan 2 bring up "MAP sensor sorted to +Vcc"

I'm pretty sure that's the code i had before.

Same code different symptoms? Surely my new MAP sensor hasn't died already?

Any help appreciated

Chris

With a little more investigating i have found that the map sensor shorts out when the engine is off or at WOT.

Any vaccum at all and it works perfect. I have confirmed this by sucking on the pipe when the engine is off and the error goes away.

Is this just a faulty map sensor or wiring issue?

Chris

Might be actaully either, at no vacuum the signal line of the MAP sensor should give ~4.75V, this is well below what ECU would consider a short to +V (I think it needs to 4.95V or so to come to such a conclusion). Best would be to test the MAP sensor off the car - connect a +5V power source and ground to approriate pins and measure the signal pin in room conditions.

But then, since you had an issue with the MAP sensor prior to that - it might as well be the wiring, I would be slanting towards something like the wiring is breaking your MAP sensors, but I am no specialist in MAP sensors (their physical design that is).

EDIT: oh, and it is the right kind of sensor, right?

Woj thanks for the reply

I have been using IAW scan2 to connect to the ECU. This only give me figures in pressure and not voltage. I will have a look to see if i can get voltage.

On graph mode under WOT the map sensor flat lines at the same point every time, which then triggers the code.

It works perfectly at all other ranges.

As you suggest i will check the wiring, what should i be looking for?

Thanks for the help

Chris

IES2 will not show you voltages, you would have to connect the sensor to a separate power source and measure the output with a meter.

For the wiring, I would start with measuring the feed that the sensor gets from the loom, chances are that for some reasons it way above 5V and hence it maxes out when getting out of vacuum.

Tested the power wire - 4.99v engine on.

I have found the issue is intermittent. Occasionally i can do WOT and get no EML. I have ordered another map sensor and hope that it's just a faulty one.

It seems worse in damp/cold weather especially when the engine is cold

Chris

So an odd thing happened today...

Found a fairly large exhaust leak on the manifold to Cat flange. Patched this up and no more Map problems!

I do however get the code when the engine is off still :s

How strange!

Chris