Hi,

I've had this problem for a year now, all happened after a service where spark plugs, fuel filter and air filters were changed.

It's a petrol 1.6L ford focus thats done nearly 53,000miles. The computer was reset 2 times in the time ive had this problem, once full power did come back for a time, untill it slowly returned to having a lack of power (after about 2 weeks)

I've really no idea what it is. It starts fine, however a couple of hours after warming up it *sometimes* takes a while to catch and start. It seems sometimes it will get more power again (but not full) and after a couple days goes back to normal.

I've noticed that it's jerky when coming off the accelerator, and that it's hesitant, dont know if these are related as when the power returned after a computer reset, it was still jerky, however not as hesitant

Theres no codes, i've checked

Took it to fords a while ago and they said it appears fine on the test, they updated the software as well

any ideas?

ide have thought that since it happened after the fuel filter was changed that seems a likely culprit if it were me id have it changmdd

Agree with artscot fuel filters are directional theres a posibility its been fitted the wrong way sort of jobs they give to the apprentice and if there not aware simple mistake to make

Agree with the answers above! Fuel filter and Air filter are the usual main causes for the sluggish performance. If all your filters where changed, then maybe they weren't fitted properly although that's a very small possibility!!

You may also want to make sure that you don't have a clogged fuel injector or a leak in the intake! Just throwing some ideas but it would be the best for the Ford chaps to scan your computer.

surely it's not the fuel filter, though? After a reset it was good for a time, untill it eventually got worse? Sensor related?

Fords already scanned the computer and said nothing was wrong!

I,D JUST HAVE A QUICK LOOK YOURSELF IF THE FUEL FILTER IS ON WRONG THERE IS USUALLY AN ARROW ON IT IN THE DIRECTION OF FLOW NOT SURE WHERES ITS LOCATED IN THE ENGINE BAY OR UNDERNEATH THE CAR

somewhere theres summat wrong if its a sensor it could be a temperature sensor to the engine which should show up on diagnostics but they will have to look at the live data not just check for dtc codes

somewhere theres summat wrong if its a sensor it could be a temperature sensor to the engine which should show up on diagnostics but they will have to look at the live data not just check for dtc codes

I have a device that can look at live data. What sort of thing do I look for?

without knowing exact measurements its hard to tell you would need to look at the fueling as well as engine temp sensors and injector patterns etc hopefully someone on here with experience using the live data can advise better

without knowing exact measurements its hard to tell you would need to look at the fueling as well as engine temp sensors and injector patterns etc hopefully someone on here with experience using the live data can advise better

ah I cant get injector patterns. I just watch live data via the OBD2 port. In fact, here is a pic I took recently (I dont know if anythings wrong here):

assuming that the car was at idle and the engine was warmed up fully the rpm is high at 804 it should be between 670-730 max if its at cold the idle is okay but the coolant temp is wrong the voltage again if cold is a bit low 14.4 to 14.5 with no load it doesnt show 02 sensor values so no idea if theres an issue there theres not enuf data u nd to be able to record the data while driving via laptop

try to test with a vacuum the turbo actuator

http://www.ebay.co.u...9#ht_2001wt_990

sorry i didnt saw that is gasoline...

assuming that the car was at idle and the engine was warmed up fully the rpm is high at 804 it should be between 670-730 max if its at cold the idle is okay but the coolant temp is wrong the voltage again if cold is a bit low 14.4 to 14.5 with no load it doesnt show 02 sensor values so no idea if theres an issue there theres not enuf data u nd to be able to record the data while driving via laptop

the car was at idle. It had been driven a lot thats why the coolant temperature is that high. I'll get the o2 readings later on and will record live data later. The voltage isnt wrong, thats the voltage for the OBD connector and not the alternators

Herre is the o2 volts readings, I dont know if these should be the right values or not