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Discussion Starter #1
Hi,

I did the MAFs testing this morning and the peak was at 55-65 Liters/h, I found it weird since the MAFs were changed before I buy my car.

So I opened the hood to see this (click for larger view) :

Driver side MAF:


Passenger side MAF :


There is no rubber around the connectors (not essential I think...), and the left one is cut !!

Does anyone know where I can buy/found this cable ? There aren't any in the scrapyards around (only french cars).
 

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The cut wire is pin 1 on the passenger side...this would be intake air temp...IF it would be needed from this side.

I can assure you,everything is perfect normal,4 wires in bank1 and 5 wires in bank2(as it read intake temp from driver side only...)...


Seems like someone messed around with changing your MAF connectors...


Do you have any error codes in the ECU?

Are you sure the test was l/h and not l/km?


with that low figures,it would barely accelerate...
 

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The rubber is not essential for proper functioning. Has your IATS been relocated?

edit: Raikku just beat me to it!
 

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The rubber is not essential for proper functioning. Has your IATS been relocated?
Not relevant,as this would be on the driver side anyway....


My guess is someone used a bank2 connector on bank1...

I just wonder if the other wires are correct pinned in again...
 

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Discussion Starter #6
The cut wire is pin 1 on the passenger side...this would be intake air temp...IF it would be needed from this side.

I can assure you,everything is perfect normal,4 wires in bank1 and 5 wires in bank2(as it read intake temp from driver side only...)...


Seems like someone messed around with changing your MAF connectors...
The engine has been pulled out (I don't know if I can say that in english :p) for a complete change of the oil, belt, MAFs, chains and vanos repair (1 changed and 1 repaired)


Do you have any error codes in the ECU?

Are you sure the test was l/h and not l/km?


with that low figures,it would barely accelerate...
Hmm, It was perhaps in l/km (second choice in the secret menu 04), I don't remember and it has a great acceleration :eek:

The only error codes I have are :

8b Cruise control system
75 servotronic speed signal
2a Vehicule speed input signal, hardwire "A" signal
87 Vehicule speed signals (Both Discrete & CAN)
27 AfterCat oxygen sensor 1 heater control
25 PreCat oxygen sensor 1 heater control
 

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Not relevant,as this would be on the driver side anyway....


My guess is someone used a bank2 connector on bank1...

I just wonder if the other wires are correct pinned in again...
I was figuring it as a botched IATS relocation in this case seeing the condition it was left in. (if you are going to cut a wire, protect and isolate it)
 

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Check the wiring of your O2 sensors....if they are connected corret.
If they are,please check fuses in the ECU box.

One of these two is your O2 sensor codes..


I think earlier in the car's life,someone broke the MAF connector on bank1 and replaced it with a used one.

Just did not bother to pin out the old not needed wire of the intake air temp sensor..
 

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1. All MAFs have a temperature sensors, but the car's harness only wires the LHS to be connected to that side's temp sensor.

2. You MUST do the test in THIRD gear...without adequate airflow you will not achieve peak values. First and second gear never see 140.

3. I absolutely agree that your bank 1 o2 sensors (both of them) are not 'connected'. When the car starts it first checks the O2 sensor preheat circuit- it ignores the O2 sensor VALUES unti the car is warm, but initially checks to make sure there is current flowing to pre-heat the sensors. IF the sensor cable is damaged or the fuses blown, you will get the preheat code right away.
 

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Codes 27 and 25 Or the two feeds are plugged together and the two sensors are plugged into each other. I have no idea how that could happen:dunno: and don't ask me cause I will lie.
 

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Discussion Starter #16
In france whe have Loue une petite amie (rent a girlfriend) ;)

Back to topic, I couldn't do the MAFs test, because the engine doesn't rev over 5500rpm (failsafe mode ?), so ~70L/h at max. I never went over 4000-4500rpm since I owned the car (about 1-2 months).

Can I reset this with the Peake ?
 

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That is a problem. Either no fuel volume/pressure or inaccurate air reporting. This is where maintenance records come into play. You did complete the MAF test, problem is you failed. If you don't know when the last fuel filter went in I would do that first. I would start budgeting for a couple of MAFs however. If you never noticed any other issues may just be the filter is restricting flow of liquid go juice. The frequency of MAF failure is very high.
 

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Discussion Starter #18
The MAFs are new, they were changed during the chain-vanos-oil-belt repair in january.

An oil filter change is planned, along with an inspection II, but I think that the 70L/h was because I was limited to 5500rpm (and it was not full throttle, because this thing revs like a beast and she was juddering at 5500rpm)
 

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I don't use the MAF test I use a scanner and read basically the same thing except it is called engine load. It goes up to 100% right away and if the mafs are not good will start to fall, I have tried the MAF test but I can't say I remember that well. I would expect it to be higher than 70 though at 5500 rpm.
You need a new fuel filter likely or maybe your fuel pump is on its way out. Hard to say without doing some tests. If you don't know when your car had it's fuel filter changed I would change it. Even if you need a pump they will make you replace your filter. MAF test is actually a fuel flow test calculated to an air volume from what I have read.
 

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Correct. The "MAFS test" is really just fuel flow rate expressed in L/hr derived from fuel injector duty cycle which is determined by inputs from the MAFS among several other sensors.
 
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