OXYGEN SENSOR

[ALP1NA]

HI Guys just need your advice on this please.

I have a 98 318ti sports and im getting very low millage on fuel.
Locally it gives me 40 miles to 20 pounds thats approx 20 litres of fuel.
On a 55 litre tank i get about 180 miles.

diagnostic shows 02 sensor and i have replaced this with a copy 02 sensor from GSF. however after clearing the fault it comes back again as oxygen sensor.

does my 318ti m44 have 1 or 2 oxygen sensors and also i dnt knw how true this is but i was told by someone copy parts dont work on bmw's as he changed a few parts on his e46 and kept getting the same problem untill he got the original part from bmw.

I have also changed the cat and this hasnt solved the problem. when driven hard i can hear a light popping sound from the exhaust but plugs are all fine dnt know why.

can any please help.

car idle's fine, no problem with starting in the morning, however a few times it did took time to start when engine was hot.

[marleymon]

get under that car and look at it! there are 2 sensors on the m44, one pre-cat and one post cat.
That popping form the exhaust sounds like you are running lean or have a vacume leak from hoses up top. Check the accordian looking boot coming off the MAF.

[ALP1NA]

Originally Posted by marleymon

get under that car and look at it! there are 2 sensors on the m44, one pre-cat and one post cat.
That popping form the exhaust sounds like you are running lean or have a vacume leak from hoses up top. Check the accordian looking boot coming off the MAF.

HI thanks for your reply ive checked under the car i can only see 1 oxygen sensor which is after the cat. Ive had the cat changed and even then it was only 1 sensor.

many thanks

[ALP1NA]

Originally Posted by ALP1NA

HI thanks for your reply ive checked under the car i can only see 1 oxygen sensor which is after the cat. Ive had the cat changed and even then it was only 1 sensor.

many thanks

Can someone please help as i can only see 1 4 wire sensor going into the eghaust after the cat, my car doesnt seem to have one before cat.unless its somewhere by the manifold.

[cooljess76]

It is. There's one sensor on the exhaust manifold and another after the cat. They're different part numbers, so make sure you get the right ones. Don't waste your money on the aftermarket junk or universals, get Bosch OEM.

[ALP1NA]

Originally Posted by cooljess76

It is. There's one sensor on the exhaust manifold and another after the cat. They're different part numbers, so make sure you get the right ones. Don't waste your money on the aftermarket junk or universals, get Bosch OEM.

ENOUGH RESPECT
Thats helped me out alot as ive brought a copy part from GSF only worked for 1 day.

many thanks guy's you been very helpful.