03 ford Exp Limited 4.6lt low power issue

[Black]

Hi all, been lurking for a while but my first post, i have a 03 ford explorer 4wd 4.6lt Limited in Black with about 60 thousand miles

My issue is hard to explain but ill give it a go.

Firstly the ex runs smooth, idles well, and changes smooth, but when you accelate hard it seems sluggish and it tends to rev hard but doesnt really pick up speed.

Under hard acceleration It holds the gears along time unless you back off slightly on the accelerator it will then change gear....

Any thoughts on what diagnosis steps to take first?
Thanks :exp:

 

[swetrid]

Could be clogged cats

 

[Black]

Had new cats fitted 6 months ago....just before i purchased it, found a receipt for the change in the service manual/records.

 

[ExPlOrErImPoRtS]

just a guess mass air flow dirty or fuel filter clogged when demand for more fuel it cant flow as needed,

 

[03 Limited 4.6]

I have the same exact truck and i am having the same problem for instance you are doing 30mph and need to change lanes to go around someone going to slow you press on the gas for passing gear to kick in it will rev up and take like 10 seconds to do anything and you really just have to back of on the gas. My trans has been changed last year and the problem was there before that. Thanks to the op for starting this thread

 

[jayton]

Had new cats fitted 6 months ago....just before i purchased it, found a receipt for the change in the service manual/records.

Well there you go. Cats are designed to last the life of the vehicle. If the previous cats failed, then whatever condition caused that failure probably still exists.

What I do to diagnose clogged cats is to unscrew the O2 sensors out of the pipes and then drive it around. This allows the exhaust gases to escape out the holes for the sensors. It will be obnoxiously loud, but if your acceleration comes back, then you know what the problem is.

As mentioned earlier, check the air filter and mass air flow meter for dirt.

 

[Black]

Thanks all,well i had just had a full service and changed the fuel filter etc etc, the(MAS) Mass Air Flow Sensor is located where exactly??? I will try to remove it and clean or change it first.

I am more a 1970- 780 CFM holley guy ...