2.2L > AT > from 30mpg to 9mg in 4k miles- no codes- no leak found- pump is fine- new filter- used lucas fuel injector cleaner 3k miles ago- now when making U turn car stutters like it doesn't know how to get into second gear. 2nd gear has always been a hard shift but that is the only other problem i've had with the car. Any suggestions would be great? WHERE IS THE FUEL GOING?!?!?!

Either the pump is going out or it could be time to change fuel filters. Be sure and use a good (LUCAS) fuel injector cleaner as injectors can get clogged with a single grain of sand. Not enough info on this car to know if it`s a manual fuel pump or in the tank. I`m assuming it`s in the tank.

Gasoline itself a solvent, therefore its an excellent injector cleaner in of itself. No additives I have ever used worked, ended up replacing things anyway. Save some money, don't buy the lucas treatment, get some new injectors installed. Might not be a bad idea to change out your fuel filter also.

Replace fuel filter.
Replace transmission filter.
If you notice a lot of debris on the tranny filter, it may be time for new bands in the transmission.

It could be a number of things. My recommendations are as follows:
-bad gas (run some bottles of lucas and injector cleaner thru)
-change air filter
-change fuel filter
-clean MAF sensor with MAF sensor cleaner ONLY
-check MAF sensor voltage readings as per service manual
-Re-calibrate throttle position sensor. They tend to need this around 120-150k miles
-check vacuum level
-check cylinder compression
-Depending on mileage and if there are any codes, replace O2 sensors with Denso only sensors
-Not likely, but the cat could be restricted too

My '01 was doing the exact same thing, and it turned out to be the MAF was dirty- and the fix took about 2minutes and ran me ~$5 for a can of MAF cleaner.

Hope this helps,
C

Check fuel pressure and see if its around 30-35 psi while under load if not replace fuel pump, also the gas thats in the tank may be no good if it has sat for so long..

I would replace the fuel filter and if you are using the gas from 4 months ago then you should put some stabilizer in the tank. Also, inspect the plugs, if they are black then replace them. If you are using new gas then put some lucas fuel treatment in, that will help if the injectors are dirty. If they are clogged then you will have to take it in to have them cleaned.

Check for vacuum leaks.

Air tube between air filter and intake manifold.

If the motor has over 80,000 miles then the intake manifold gasket can **** in air and leaning out the air/fuel mixture.

Give each air / vacuum relayed hose a 1/8-1/4 turn.

Get a steam cleaning on the motor and check for any sign of leak around the sensors.

try swapping #1 injector with another injector to see if the code jumps to another cylinder. maybe possible that the injector maybe clogged cause a misfire code. best to change with one in the front. dont know what p0405 is off hand. is it an evap code? try swapping the injectors first the clear the code and see what comes back

If no codes or check engine light, then I'd start by changing fuel filter. When was tune-up, & filters changed last?

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