Range Rover 3.9 petrol Vogue se (Bogging down under power Please help)

Hi All,

Any clever Range Rover pro's out there this must be a common fault,

Our Range Rover starts and runs fine, Intermitently when you throttle up the road tends more uphill but does down engine starts to bog down like limp mode !!! let off the throttle and slightly accelerate it will keep running fine at about 25 mph but throttle further it just bogs out, but never cuts out, pull over and rev engine up fine just happens when moving along,

But fault will not go unless while moving I switch ignition key Off and back On again, fault will clear and be fine until it happens again maybe 5 mins later

Any ideas anyone

regards Scott

check the air filter, sounds like its struggling to breathe.When was last service?

Switching the ignition key off?? mmmmm.......... try plugging in a different ECU. The other things to check maybe throttle potentiometer (throttle pot).

Other than that you might want to look at fuel system - filter, pressure regulator, fuel pump and relay. As Goonarmy says do check the air filter but it sounds like the problem is under load, does it make any difference if you feather the throttle?

Hi,

I have removed air filter, still does it,

With lack of parts I have disconnected most parts one at a time to check for similar simptomes but nothing,

I have replace Air Flow meter, still no different, It must be electrical if the problem clears by working the ignition switch on and off ???

If you slowly throttle it up i think you can drive through it eventually, What about the Ignition amplifier module ive heard they can cause similar faults ??

Scott

Ignition amplifier will cause misfire - usually when hot. AFM fault likely to cause EFI warning light to come on but if fault with ECU warning light may not come on. That's why I suggest you get hold of a substitute ECU - make sure you know it is a working ECU. Assuming you are on a Lucas 14 CUX there are different part numbers for it but all are the same, at least I know PRC7081 and AMR1424 are interchangeable with the exception of a mounting bracket, but for test purposes it doesn't matter.

Is that the part No on the ECU,

Am i right thinking its under the Drivers seat ??

Does anyone have One i can borrow and try

Regards Scott

Anybody,,,

Cheers Scott

Doe's anybody know where I can get a ECU to try,
Or have any other Ideas what to try ???

Cheers Scott

Hi Mate,try a new fuel filter,its under the car at the back on the right chassis leg(near fuel filler).if its not been changed for a long time they can block restricting flow.
Turning the ignition on and off flicks the fuel pump on and off which can temporarilly ease the blockage,seen a few cars suffer from this(cost about£10.00,looks like a tin of beans with no label on)....,chris.

Hi Chris,

Cheers was about to do that then checked out electrics with haynes manual and found Faulty TPS, Found one at Scrap yard
and now runs like new,,,,,

So sorted

Cheers Scott

Hi
I had the same symptoms a few years ago with my 3 series BMW, it turned out the catalytic convertor had disintegrate had it replaced and hay presto back to normal, it was weird as soon as you put your foot down it sped up for a second and hen dronned to a low speed no matter what you did (even down hill)

hope this helps.

BTY My Vogue (just picked up yesterday) has completely died on me no electrics at all, nothing can not even turn the key, no hazards anyone that can help please do, just waiting for the RAC man to turn up.