Why is my Allion using so much gas ?

Any difference in performance? reduced acceleration? think that perhaps the PCV valve is dirtied up and need to be changed. right routine in terms of service is cheap...couple of bucks..change your air filter too~

Thanks Roy - No difference in performance or acceleration. Only a time- lag after pressing the gas pedal, which I understand is a problem with all the D4 engines ?

swear, the PCV (positive crankcase ventillation) valve which is cheap, does not exist for your car...look for an elbow what connects the valve cover to the intake plenum....not sure why/or how this eludes the parts search, but am quite sure you've gotta have something like it there~

cannot seem to locate the D4 engine...there are three different flavors of L4 engines....mysteries abound...still no PCV valve, you really cannot go without one...which country is this car in...maybe the search would become easier if I knew which part of the planet to start looking in~

judge-roy, This Allion is in Jamaica, and was bought from the Japanese domestic market. Thanks, John

is it a diesel? that may narrow the search...thanks for getting back...yah mon~

http://www.fixya.com/tags/toyota_d4_engine

No, it's not diesel, it's petrol, and I'm using 90 octane, which is the highest available in Jamaica.

lets see if number one DavidH25 has a clue...he's really good with Toyotas~

First it has to have some sort of PCV, some kind of Crankcase Ventilation, I don't care if you are on Mars, blowby from normal running gets past rings and will build up in crankcase without it and actually pressurize the crankcase, In days of old when Knights were Bold they were simple vents, then somebody thought, "hey. why don't we suck it back in to the intake"? But it has a PCV and a valve. Somewhere,...OK 8km /liter is, um, right about 20mpg. let me look around

OK Here is D4 and see the hose? It will get bigger

And another D4. And it's rated, not by our beloved EPA because it's not available in North America, but by Toyota at 28Hwy/21City.. So 8km/Liter is right about what you should be getting. The D4 is no longer in production, it is not legal for use anywhere in the world that has any emissions standards. In Jamaica all the crap in the air is promptly blown out to sea, and the little fishies in the Atlantic don't care, and the flying rats aka Seagulls, well let them have it. There is no market for the engine, so Toyota discontinued it. There was something interesting I found, that on the diesel version uses what they call "ultra high" fuel pressure, to the tune of 19,000psi in the rail. No typo. 19,000psi.. End of story? If you do a lot of City diving, and if your driving habits are such that you stomp on it from red lights to get away quick, your 8km/L~~20mpg is all you are going to get. It is normal. In the above picture the valve is hidden but that's your PCV hose. below is just another shot of the motor

One more thing: I don't know what they have in Jamaica, but continue with the 90 octane. This is a 10.5:1 compression engine and needs the better fuel, and if possible buy gasoline with detergents in it.

OK, Thanks a lot, DavidH25 and judge-roy. Guess I,m stuck with this thing then. You know, I never would have thought Toyota would have released such an engine without first thoroughly testing and proving it. Rgds

Thank you H25 for comin' to my help once again...you my friend are the sentimental gentleman if ever...

Hey gentlemen I aim to please