1kz-te poor fuel consumption

[jsj4341]

AOA,
hope all of you are doing fine
I have a land-cruiser Prado 1995 with 1kzte engine for about 2 years and has been used for really long trips and for inter city driving..it used to give 10 to 11 km/l on highway at approx. 100km/h and 6 to 7 km/l in city...... but for about 5 months ago suddenly it drops to 7 km/l on highway and 4 to 5 km/l in city.

air filter, fuel filter, oil filter, oil changed, A/t transmission fluid changed....... even injectors were cleaned recently.... but no luck so far its the same no change.....

a major thing that was replaced was the ECU shortly after the journey from karachi.. original was not available so it was replaced with the ecu of 1kzte surf engine(i guess 1996 to 2002 model) .....after replacement it is running good no loss in power but an increase in it ..all the function and sensors are working perfectly but fuel economy has been affected for some reason..

          any help or advice would be highly appreciated...thank you

[Xulfiqar]

is the engine mechanically in good tune? like valve clearances, EGR not blocked etc. Turbo boost pressure good... etc.

[jsj4341]

yes sir it is indeed tune to the factory setting (according to its workshop manual)...secondly ihave no idea about the boost pressure today i might install boost gauge and will let you asap. the egr is partially blocked as i have pulled out the vacuum hose (not with blanking plates,but planning to block it in future)(egr is closed because it used to stay stuck open causing the car a loss in power and dense black smoke all the time).... another test that i performed yesterday was that intake manifold pressure test and found out that egr valve is leaking air!!!

[nauman]

@xulfiqar sir i have a querry.. i bought 1.8 altis.. 1zz fe.. odo 221km it was standing for almost one year.. cranked it it starts on first attempt with rattling sound.. then it dissapered oil level was full.. after wards have changed the oil.. the coils electriction said that 3 are of 660cc alto and one is of vitz.. now it is emitting white/blue smoke if u give the throttle on idle or even if u driving n also alot of black smoke.. car is also giving some.missing as well.. also water was clean no rust signs in that n no bubbles.. mistri sab sab that.. change the coils plugs and also do the tappets as the are jammed due to not being running so after that white/blue smoke will end.. so any suggesstions xulfiqar bhai what should i do

[nauman2201]

Ur new ecu is not ment for this transmission (a343f) so u do not get the o/d 4th gear. That is why the jeep uses more fuel as it remain in third gear. I would suggest that u should put in the orignal ecu or remain in lower speeds ( may be around 65km

[shaheerali007]

is the engine mechanically in good tune? like valve clearances, EGR not blocked etc. Turbo boost pressure good... etc.

zulfiqar bhai where is actually EGR in 1kz and how to clean it bec i have prado for more then 3years and never cleaned it