hi there,i have used the cleaner on the contacts & sensors of the MAF as well…allmost sucess ! ,can i spray the connections on the multiplug that plugs onto the maf,( toyota rav4 2002 D4D 110’000 miles)only i’m still getting the odd slight engine

If it were the clutch, it would be because of it being slipping and you would smell it burning. I really doubt it is the clutch and also doubt it is caused by the spark plugs.

Does the check engine light is turning on?

Looks like you are having some lean mixture problems. It could be that fuel been injected is too little for compensating the air entering the engine, making it worse when flooring the gas pedal. Also, if it happens more at cold conditions, it will reinforce this theory, as in those conditions (cold), oxygen is more concentrated in air per volume, making the mixture leaner if not properly compensated with fuel.

On the other hand, if it was because of a too rich mixture, you would smell too much gasoline when flooring the gas pedal and even black smoke would come out of the exhaust.

Indicators? Well, the best simple indicator is to check the spark plugs. A too lean mixture will make the electrodes ashy or white. A too rich mixture will make it sooty black. An oil leakage will make it oily wet and a normal mixture will make it reddish brown.

If you find out that it is a too lean mixture, which is the one I am suspecting, it is because of any sensor that controls the mixture. The oxygen sensor does, but it is ignored by the ECM at wide open throttle (flooring the gas pedal), so we have left the MAF sensor. May be it is not dirty, but damaged.

You may also have too lean mixtures because of too low pressure in the fuel rail (bad fuel pump) and will be noticed at acceleration.

I would start by checking the MAF, if possible, by trying another one. I would also check the spark plugs to confirm the burning conditions as explained above and for the fuel rail pressure, there are instruments for measuring its pressure. If it is below 40 PSI and dropping when accelerating, you may have a fuel pump problem. For both, the 1ZZ-FE and 2ZZ-FE engines it should be from 44 PSI to 50 PSI.

I hope it helps.

Richard

I notice that when I really put the accelerator down hard, trying to accelerate quickly, it’s still the hesitation and then a revving of the engine before the speed slowly crawls up. A neighbor suggested this is probably spark plug wires as it seems worse in the winter and rain. Do you think that’s possible or is my mechanic right and I’m just going to have to cough up the money for a new clutch?

Many thanks,
Tara

Yes, it should be in the same place in most Toyota models of years 2003 and later.

Sheers,

Richard

I’m going to give this a shot! Would it be in the same place for a Toyota Matrix?

This will apply for most Toyota MAF sensor from models from 1999 and later.

Hello Sean, thank you for your great feedback.

Richard

The Aveo does not use the MAF (Mass Air Flow) sensor. It instead, uses the MAP (Manifold Absolute Pressure sensor).

If you still need to find the MAP (not the MAF), then it is located in the plenum, which is the part at the rear end of the air path, and it has 3 wires; WHITE, LT BLUE and LT BLUE.

This cars base their fuel delivery calculation on engine load by measuring its absolute pressure instead of basing it on air mass flow as their counterparts that use MAF sensors.

Best regards.

If you want to try the cleaning in your car, it would be similar. Just spray the chemical in the apertures of the sensor while uninstalled and leave it to dry completely before putting it back. The location of the sensor is drawn below.

Cheers.