Intermittent low fuel pressure (P0087 - to low)

[JimA4B6]

Hi Folk,

So had this low fuel pressure problem when i first purchased the car (a 2008 2.7tdi, auto). I fixed this by changing the fuel filter roughly 4 months ago. So now i have this code P0087 too low, the car is not hard to start or low on power and no other noticeable signs other than specifically, once i slow down from high acceleration i get the glow plug light and limp mode, engine off and on then we are all good again. If i drive the car easy i have absolutely no problems and great mpg.


After a google search i am going to check the pressure regulator for aluminium swarf and work back to the fuel tank

Any additional advice on this would be lovely.

[JimA4B6]

I temporarily fixed this with a fuel filter change and a fuel regulator change, it was excellent for 6 months but now it has returned with different symptoms, same code. It happens when i try to accelerate from cruising. I'm wondering is this to do with the cold weather and the location of the fuel filter on these A4's?

5211 - Fuel Rail/System Pressure
P0087 00 [101] - Too Low
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Mileage: 206158 km
Date: 2021.01.07
Time: 13:50:19

[JimA4B6]

Today after no driving from my last post the car is back to its normal self only difference is we are +9 degrees C from it had faults. I may be ignorant to something but i'm putting this issue down to a very cold start (relatively) and the redex i had put into the tank which possible had clogged the filter in low temps.

[philipharmes]

Have you checked the in-tank fuel pump is pumping reliably. ( assuming this car has one )

[JimA4B6]

Hi Philip, I have not checked this, is it a VCDS check? looking online you can buy this item for the 2.7 B8 so i'm guessing it exists in my car.

[philipharmes]

Pretty sure it doesn't show in VCDS.

You could try un-plugging it & checking.

But of course that doesn't prove it's pumping properly.

Best of luck Jim.