MAP sensor

[Guest]

An auto electrical engineer was surprised to find the MAP sensor vacuum pipe on my 150 Sigma engine was capped off but was still connected electrically. The car runs fine and has been inspected by Caterham post build. Can anyone explain the reason behind this?

Thanks

Pete

[ChrisC]

It's my understanding that the MAP sensor information was removed from the latest ECU maps for the 150, so a am not suprised by your configuration. I suspect it was easier to leave the redundant sensor in the loom instead of creating a new engine loom.

 

 

 

Edited by - ChrisC on 30 Nov 2013 08:16:16

[Guest]

thanks Chris I thought it must have been intentional but couldn't see the reason Pete

[Mr Locust]

If not connected to the engine, is it being used to to check barometric pressure in this application?

[ChrisC]

I understand the ECU does not use any information on manifold pressure, only throttle position, after the final changes made for drivability.

 

These being

 

Change in throttle quadrant (larger)

Map change

Remove MAP Sensor

Stronger throttle return spring

Changes to cam belt tensioner

 

 

[Jason Plato]

it will need a map sensor if you go to the alps !

[ChrisC]

No if the ECU ignores all the information coming from it.

 

Edited by - ChrisC on 30 Nov 2013 16:57:02

[Jason Plato]

so how is the fuelling going to be reduced then ? if the map sensor is not present ?

[DJ.]

Quoting Dave Jackson: 

so how is the fuelling going to be reduced then ? if the map sensor is not present ?

 

Good question.

 

Duncan

[ChrisC]

Don't shoot the messenger, the MAP Sensor was remove with the 150 map version H here since 2009

 

Edited by - ChrisC on 30 Nov 2013 20:13:30

[7 wonders of the world]

The ECU can adjust fuelling by use of either/or hot wire air flow meter and the use of dual lambda sensor pre and post cat.

 

The pre cat one registers fuel emissions before the cat and is best placed to keep fueling within prescribed limits.

[geko]

Hi,

 

the map sensor (if still connected) or a internal pressure sensor in the ECU can also measure the barometric pressure to correct the fuel mapping for high altitude.

It is a matter of the ECU map to change the sensor inputs from MAP to barometric correction.

 

 

Edited by - geko on 30 Nov 2013 21:42:45

[Beejay993]

Hi, does anyone know if you can only buy the MAP sensor directly from Caterham or can it be purchased directly from Ford ? I presume it's a Delphi part...?

[John Hughes]

The fuel is calculated by the tps / engine speed, there are then correction factors applied relating to engine coolant temp, air intake temp, alternator voltage, barometric pressure (map sensor) Lambda under certain conditions.

 

As far as I can tell the map sensor is used in certain Vauxhalls and Volvos

 

They can be got from eBay cheaply but a check with Easimap is useful to confirm they are giving the right output.

 

Edited by - John Hughes on 24 Jul 2014 20:29:48