Peugeot expert van 1.9 D 70 - Engine management light

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Sun 20 Jul 2014 00:58
Peugeot expert van 1.9 D 70 - Engine management light - lawkid
The engine management light comes on and the engine starts making a knocking noise. Sometimes this only happens for a few seconds, other time it goes on for about a week and stops.

After this the van drives fine for a month or more and then it happens again.

I think it happens more often in wet weather if driving through deep puddles.

It has been looked at by 3 garages and they have said

MAF sensor, faulty wiring or high pressure diesel pump.

Any suggestions would welcome.
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Sun 20 Jul 2014 09:47
Peugeot expert van 1.9 D 70 - Engine management light - Peter.N.

I didn't know the 1.9 had a MAF sensor, what I believe it does have is a timing sensor on one of the injectors, this could be intermittently faulty or the wiring to the pump or the pump itself. Try disconnecting it and see if it gives the fault symptoms.

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Sun 20 Jul 2014 12:06
Peugeot expert van 1.9 D 70 - Engine management light - lawkid
I have double checked both the vehicle model to make sure I have given the correct info.

There is a MAF sensor next to the air filter,

I have tried disconnecting the sensor you mention and it makes no difference
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Sun 20 Jul 2014 12:10
Peugeot expert van 1.9 D 70 - Engine management light - lawkid
I have also been told that it could be caused by water entering the air intake system, as this problem also happens when it is dry I don't think this is the cause but I will check all the intake hoses to make sure they are watertight.
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Mon 21 Jul 2014 19:27
Peugeot expert van 1.9 D 70 - Engine management light - Peter.N.

If disconnecting the MAF makes no difference that usually indicates that its faulty.

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Mon 21 Jul 2014 22:32
Peugeot expert van 1.9 D 70 - Engine management light - lawkid
Ok thanks I will try changing it
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Tue 22 Jul 2014 15:05
Peugeot expert van 1.9 D 70 - Engine management light - Gibbo_Wirral

If they had decent diagnostic equipment they'd be able to give you a more accurate diagnosis.

A faulty MAF will report a fault code in the region P0101 - P0104. But not only that, live data will tell you the current and intake air temperarure at the MAF. That way you can tell if the MAF is faulty or its the wiring. It could even be dirt in the electrical plug.

If your van has the DW8 engine, or the 90bhp HDI then the engine warning light doesn't come on with a faulty MAF.

As for the "high pressure pump", I'd also treat that with suspicion. Fault codes can show up for that if there's a problem with the lift pump in the tank (if it has one), an air leak on the priming bulb or even a clogged fuel filter. For the price of them I'd recommend changing every 12,000 miles.

Again, reading the live data as the car is cranking will tell you the fuel pressure and pinpoint more accurately where the problem is.

Edited by Gibbo_Wirral on 22/07/2014 at 15:07

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Tue 22 Jul 2014 22:41
Peugeot expert van 1.9 D 70 - Engine management light - lawkid
When on diagnostic machine the fault P 104 did come up and this is when they gave me the options mentioned in my first post.

Can you tell me which component is connected to the MAF and where to find it.

I am wondering if it is low down on the engine on the drivers side as the problem occurs more often when I drive through standing on this side.

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Wed 23 Jul 2014 15:21
Peugeot expert van 1.9 D 70 - Engine management light - Gibbo_Wirral

The MAF usually sits after the air filter box. There should be an electrical plug going into it.

I'd start by unplugging, checking the wires for any damage then giving the plug and socket a blast with electrical contact cleaner.

After that, maybe take out the MAF and look at the wires. They're very fine and can break over time.

I'd get a Peugeot Planet diagnostic, as that can read the live data values at the MAF - voltage, current, air temperature and airflow.

There's a network of Peugeot owners around the country with the Planet diagnostic equipment who can help you out. Find your nearest on this map:

maps.google.com/maps/ms?msid=214397633218647067111...e

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