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Hi folks,

Just bought a 2002 Laguna IDE as a 'project.'

It seems to have the commo 'fuel regulator' issue, whereby it cuts out when sitting getting hot in traffic, and will not rev over 3k revs.

I understand that this is a very common problem?

Which part, in your opinion, should I change first?

the regulator itself, or the fuel pressure sensor?

Cheers folks!!
 

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Hi folks,

Just bought a 2002 Laguna IDE as a 'project.'

It seems to have the commo 'fuel regulator' issue, whereby it cuts out when sitting getting hot in traffic, and will not rev over 3k revs.

I understand that this is a very common problem?

Which part, in your opinion, should I change first?

the regulator itself, or the fuel pressure sensor?

Cheers folks!!
First, don't worry too much... you can fix this.

My experience...

I have an 02 plate Laguna that I've owned since new.
Until 2 month ago I've had no engine problems (except for a very slight rough idle).

At that time the other half had problems with the car reporting injection and ESP problems but not going into limp mode.

This got steadily worse over that last month. Last week the car finally started to go into limp mode or just cutting out.

The Clip showed stored faults with both the fuel regulator and the ESP. Deaper investgation required.

I graphed up the fuel pressure and regulator control (standard Clip function) and this is what I found...

IDEFail.gif

I put the red lines on the graph to show the following..

1) Engine started. It was already warm
2) Proper pressure regulation starts with about 68bar
Note however that the regulation signal RCO is steadily dropping from the correct value of about 35%
3) I increase the revs to 2K. This is where things go wrong. The regulator does not manage the fuel pressure which increases to 110bar. The RCO signal goes to 0% to compensate but the pressure is still high.
4) At this point the ECU has determined that it can't regulate the fuel pressure so goes into limp mode. Note that the RCO output is fixed at about 30% and the fuel pressue follows the engine rpm.

The fuel pressure was all over the place, especially when warm. The control signal to the regulator seemed to try to correct the pressure variation but without success. Diagnosis: the pressure regulator was not doing it's job.

Sourced an new regulator, fitted and ran the test again. Fuel pressure properly regulated.
Now the fuel rail looks much better. Car drives well with no signs of limp or cut out.

This graph shows the test drive after replacing the regulator...

IDEOK.gif

Pressure now varies between 50bar and 90 bar.
At idle it is about 70 bar. Under load it rises to 90 bar. When the engine rpm are slowing the pressure drops to about 50 bar then comes back to 70.

The engine runs sweet now.

p.s. The ESP fault is as a result of the ESP computer not getting signals from the main ECU when in limp mode. This is not a fault with the ESP but needs to be cleared on the Clip.

Cheers,

Ian
 

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Nice work Ian.

Paul
 

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Thanks for this. You have given me hope.



Specialized equipment needed or will I be able to do this as an amateur?

Where did you manage to source a replacement?

Thanks in advance

David
Regulator is dead easy. Four torx screws on the engine cover then two screws either side of the regulator.

Things to note...

1. Cleanliness is very (VERY) important. I had the replacement ready in a plastic bag. Removed the screws and swapped them straight over.

2. Be careful when removing the connector on the regulator. I removed the clip completely then fitted it back afterwards.

3. Wet the o-rings on the new regulator with a little clean engine oil before fitting.

I got my regulator off e-bay from a breakers in Accrington but picked it up in person. It was removed from a fuel rail as I watched and I placed it directly in a plastic bag.
They assured me that the rails were new although they looked like water damaged stock to me.
The regulator is at the far end of the rail (from the fuel inlet) so is unlikely to get contaminated.

It's my belief that most of the multiple failures of the regulator are caused by contamination when they are replaced.

Best of luck,

Ian
 

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Make sure you check the small filter at the bottom of the regulator port for blockage or even if it's collapsed.

I've been looking at a Laguna with the same problem even after the customer had the regulator replaced at another garage and the same problems persisted.

It wasn't untill I removed the regulator when I noticed that no fuel was coming out of the small port at the bottom of the rail so I pushed a small screwdriver in the hole and a small rush of fuel came back up through the hole.

It appears that the filter has collapsed causing a increase of fuel pressure after the vehicle has been running for a while.

Not sure if you can get the filter on it's own or if it has to come with the rail.
 

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