Lumpy Idle and Sluggish to Rev 1.8 Freelander

[emeye]

Well I finally managed to get my freelander to a garage to replace the fuel filter along with some other jobs, but unfortunately whilst there have been some improvements the car is not 100%

It now starts without problem, but the idle is lumpy and the throttle response is sluggish, especially so from cold - when you press the throttle there is an initial delay before the revs shoot up and it always feels underpowered. I feel I have to rev it much harder than should be necessary to make reasonable progress!

Everyone seems stumped - coil, dizzy, rotor arms, leads, plugs, injectors and inlet manifold have all been changed as has the coolant temp sensor.

I have read that the aftermarket coolant temp sensors can be dodgy, but I'm reluctant to throw more money at the problem, especially to replace a new item!

Could I be sucking in air somewhere? Could it be the plastic throttle body?

Any suggestions?

Cheers.

[FridgeFreezer]

Have you checked for air leaks etc.? Is it using lots of fuel? The coolant sensor is only a tenner or so, as is the air sensor, and both are dead easy to change.

[Ally V8]

It would be a good idea to get it on Testbook or similar and see what all the sensor readings are saying in live data displays.Esp the Map sensor,throttle angle,coolant temp and the oxygen sensor.

If its been running badly,ie misfiring then its also possible the matrix of the cat has broken up and is partially blocking the exhaust.Easy to test,just undo the downpipe to cat joint and prop the joint open,see if it runs better.The engine ecu itself has been known to fail too.....