What causes low Actual Air Intake Quantity on 115JTD

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SillyBilly
Posts: 12
Joined: 12 Nov 2010, 17:55

What causes low Actual Air Intake Quantity on 115JTD

Post by SillyBilly » 24 Aug 2011, 15:33

Hi
Old problem: I had a smokey 'throttled' engine but have now found that the intake pipe had come off the intercooler. It now runs fine.
New problem:
When I use Multiecuscan to check the parameters Actual Intake Air Quantity and Desired Intake Air Quantity, I find that the Actual readings are between 10% and 20% of the Desired.
I have swapped the MAF sensor with that on another 115JTD and the figures for Actual Air Intake Quantity on both are the same as they were, so not the MAF sensor.
I have checked the EGR valve and cleaned it out, though it wasn't blocked or stuck.
I have checked the Intake Butterfly valve and it isn't stuck.
I have checked the pipes and connectors.
There are no faults reported by FES
The car passed its MOT emissions test last week
Any help would be appreciated. Help!

coolbits
Posts: 17
Joined: 10 Aug 2010, 08:44

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by coolbits » 25 Aug 2011, 08:35

Those values are probably in kg/h...

viewtopic.php?f=3&t=1357

SillyBilly
Posts: 12
Joined: 12 Nov 2010, 17:55

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by SillyBilly » 25 Aug 2011, 09:54

Hi
Unfortunately not. Both Actual and Desired figures are in mg/i

coolbits
Posts: 17
Joined: 10 Aug 2010, 08:44

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by coolbits » 26 Aug 2011, 07:14

How do you know that? Because multiecuscan says so?
I have mg/i in program too but the actual values in real are in kg/h... Desired values are in mg/i, that why you get only 10-20%...

If your car runs fine otherwise than this is it.

SillyBilly
Posts: 12
Joined: 12 Nov 2010, 17:55

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by SillyBilly » 26 Aug 2011, 08:12

Hi
Maybe
But if that was true why on my other Multiplawith the same engine does the same software give figures almost exactly the same as the Desired ones?

coolbits
Posts: 17
Joined: 10 Aug 2010, 08:44

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by coolbits » 26 Aug 2011, 08:34

I posted you a link to my thread where developer explains why...

SillyBilly
Posts: 12
Joined: 12 Nov 2010, 17:55

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by SillyBilly » 26 Aug 2011, 09:13

Hi Coolbits
I didn't see your link only the kg/h bit
I can't check the ecu software verion becuase the battery is off the car and the intake is in bits. So sanscorp is not the only one who has been sent on a wild goose chase!
The problem is that my figure is 32.2 kg/h? not the 48-50 mentioned. I have put a pic of the FES trace on the multiplaowners forum, link below. Is this consistent with this bug?

http://uk.groups.yahoo.com/group/multip ... =1&dir=asc

coolbits
Posts: 17
Joined: 10 Aug 2010, 08:44

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by coolbits » 30 Aug 2011, 05:50

I do not have yahoo account so i cant see the link...
Anyway 32.2 is too small for sure.

ARomeo
Posts: 86
Joined: 06 Jan 2010, 10:45

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by ARomeo » 07 Sep 2011, 02:37

Turbocharger, air filter

SillyBilly
Posts: 12
Joined: 12 Nov 2010, 17:55

Re: What causes low Actual Air Intake Quantity on 115JTD

Post by SillyBilly » 07 Sep 2011, 08:08

No they are fine.
I am told that it is a bug in Bosch's software in the ecu and until I find a way to upgrade it I will have to live with it. I could probably get Fiat Examiner to do it but dont have that sort of money. Am looking into using my EEprom programmer to clone the chip on the ecu from my other Multipla's ecu. Has anyone done that?

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