I recently bought my P38 4.0 lt HSE with LPG conversion and am bitterly disappointed with its performance. At normal driving it appears fine but under hard accellerating or under load on a hill it has a severe flat spot in the rev band around 2700rpm. If i kick down hard it does respond but as it auto changes up again it again loses power. I bought it to pull my caravan but on a recent trip at the first sign of a hill or a motorway incline i lost power so much that all the trucks were overtaking. It does this on both petrol and LPG. I have read that this is one of the problems that RR's have, but can be overcome by buying a different chip and / or remapping. The cost of this I believe is around £850. Is there an alternative or some other solution or suggestions. I cannot accept that this is a symptom of a V8 powered Range Rover. I recently bought my P38 4.0 lt HSE with LPG conversion and am bitterly disappointed with its performance. At normal driving it appears fine but under hard accellerating or under load on a hill it has a severe flat spot in the rev band around 2700rpm. If i kick down hard it does respond but as it auto changes up again it again loses power. I bought it to pull my caravan but on a recent trip at the first sign of a hill or a motorway incline i lost power so much that all the trucks were overtaking. It does this on both petrol and LPG. I have read that this is one of the problems that RR's have, but can be overcome by buying a different chip and / or remapping. The cost of this I believe is around £850. Is there an alternative or some other solution or suggestions. I cannot accept that this is a symptom of a V8 powered Range Rover.Hi rewmer Mar 2000
rewmer
Well-Known Member
Sounds like a later Thor engine with the Motronic engine mangament then. These are quite nice units and dont suffer from flat spots. It would seem you have problem somewhere. First thing to do is get the ECU read for fault codes and then go from there.
Give it a service with a set of new NGK BPR6ES plugs, air filter and oil change, and then go from there. If your still unhappy my first thoughts would be the MAF sensor.
Give it a service with a set of new NGK BPR6ES plugs, air filter and oil change, and then go from there. If your still unhappy my first thoughts would be the MAF sensor.
My 4.6 Thor has got a terrible flat spot that is baffling the mechanic!
rewmer
Well-Known Member
Which obviously means there is a problem. The point I am making is when running right, they pull smoothly right through the range without flat spots. If you have one then there is a problem.
