Dear Pakwheelers Assalamualikum,
Sorry for a long, first, post but I hope will be able to get good from members for recent problem being faced with my City idsl 2007 manual.
Every week i drive from ISB-LHR-ISB. When bought this car was dirven 94K kms. Now in about two years its around 190 k Kms.
Been very careful with changing oils on time. Been using ZIC A(X7) changed from Zic A+ after 100K kms changed after every 3500 kms. Get MTF changed every 40K Kms. On highways i try to keep rpm between 3 and 3.5 and rarly go to 4.
Recently while driving from ISB-LHR due to foggy condition drove it for 180 Kms at about 140Kms had crossed kallar kahar when check engine light (CEL) started to show. Turned off the engine waited for a couple of minutes and after restarting engine the CEL was gone. Things went well.
On way back to ISB there was a drastic change in engine power as in third gear I was not able to take it beyond 40 km/h ( with total three passengers). I could clearly feel that engine is struggling to maintain even 40 Km/h. There was no CEL. For the first time the meter went to reserve on arriving ISB. The car behaved normal for in city driving.
Over weekend CEL again showed on way to LHR. repeated the procedure and it was gone again. near kallar kahar i could again feel low engine power. Every now and then I had to pull back my car in the middle of overtaking other car as it wont accelerate enough. after CEL, with speed between 100-110 I drove it to LHR.
Tonight on way back to ISB the low engine power persisted however it was slightly better than before as I could accelerate up to 60 Km/h in third gear on Kallar Kahar ( single passenger though
)
Near ISB Toll Plaza the check engine light again showed and the car suddenly started to show signs of trouble. Parkd it on side and repeated the procedure. CEL was gone but car idle was a bit odd. The indicator dipped very low. With out any clue at low speed moved and got home.
Current Maintenance Status:
Engine Oil changed and toped up ( new oil filter & air filter)
Coolant toped up
MTF change due after 20K kms
26K Kms Driven after last Spark Plugs change (Normal NGK R) 
Fuel Filter & Pump never changed ( its been driven on petrol , CNG installed but not used since last 96K Kms)
Clutch & Pressure Plates never changed
Never had the ECU checked or any sensor changed
No work done on Catalytic Converter ever
I am looking forward for reply from senior member to guide me on
With best Regards,