Rich Mixture

[merlin75uk]

Hi i have a K reg Carina E 2.0 i Executive, on the last mot it failed on emisions, the enging is running rich all the time and is using excessive fuel, i did suspect the 02 sensor but my mechanic told me as the enging warning light does not come on it may be a mechanical fault, any help with this would be greatly appreciated, i have had new platinum plugs fitted recently and the old ones were not oiley just the normal light brown, the car is used mainly for work, 6 miles per day, so mostly short journeys.

[BALIKBAYAN]

Hi,

Are the newly fit plugs oily? Is it the same type of plugs? I understood by your post that this rich mixture problem started after the sparkplug change, am I correct?

As far as I have understood these modern engines with O2 sensors and ECU, the O2 sensor tell the ECU to increase or decrease the fuel to get the correct mixture.

Does the engine burn lube oil? It was just a thought I had that the rich mixture might be lube oil.

[merlin75uk]

Hi,

Are the newly fit plugs oily? Is it the same type of plugs? I understood by your post that this rich mixture problem started after the sparkplug change, am I correct?

As far as I have understood these modern engines with O2 sensors and ECU, the O2 sensor tell the ECU to increase or decrease the fuel to get the correct mixture.

Does the engine burn lube oil? It was just a thought I had that the rich mixture might be lube oil.

Hi new plugs were fitted last year i think in March when i had the cam belt changed and a new heavy duty tensioner fitted, this problem started last year but passed the mot on tickover, this year however it failed and the garage let it go though anyway, but i have to get this sorted before it gets any worse, incidentally the car starts no probs hot or cold, but is a bit erratic on tickover, and last week the engine stalled for no apparent reason at a junction i have had the distributer reconditioned because the coils failed about two years ago, but i still have the original ht leads and cap as far as i know. on tickover especially when hot the engine seems to falter and wants to stall sometimes, i am just trying to save a bit of cash cos it will be expensive the have it done by a toyota dealer.

[KPARRIS-JONES]

The O2 sensor is the most likely thing, remove it and give it a good clean.

There shouldn't really be any other reason for it to fail, are you sure that you have chosen the correct spark plugs?

[Raistlin]

The O2 sensor is the most likely thing, remove it and give it a good clean.

There shouldn't really be any other reason for it to fail, are you sure that you have chosen the correct spark plugs?

Damn your good

[toytech80]

IS IT A 3S-FE HAS THERE BEEN ANY HEAD WORK CARRIED OUT THAT YOU KNOW OF,HAD A GUY WHO TOOK OUT THE CAMS AND DIDDNT PUT A SERVICE BOLT IN THE SCISSOR GEAR AND THAT RAN RICH

[Old Red Celica]

Does it ever get a good run?

Was the cat really hot when you took it for the MOT?

[merlin75uk]

The O2 sensor is the most likely thing, remove it and give it a good clean.

There shouldn't really be any other reason for it to fail, are you sure that you have chosen the correct spark plugs?

Damn your good

[merlin75uk]

The plugs were fitted last year in Feb i think, but i did not get them, a mobile mechanic did, he said they were the platinum tipped jobbies and should last 60 K, think they might be nippondeso, as far as i know the engine is a 3f-SE and has not had any head work done, it did have a new cam belt fitted last year same time as the plugs. Has not had new ht leads or cap, the cas has not had a long run since may last year , the garage said that over the last 3 mot's the emmisions test has been getting harder to pass, as i have not had a new 02 sensor i presume its a good bet that it has had it, and i may need to replace. As a matter of interest how exactly do you clean one ? ony the manual says it is very delicate.