99 Fault Code?

[bootzey]

Hi All. I have a 99 fault code on my P reg 1.8 auto. I did have a 31 code as well but cleared that.

I'm trying to suss out why the car uses alot of petrol but passes the MOT with ease. On short runs, i.e. about 10 mile round trip with a stop half way, the fuel gauge will go from 1/4 to virtualy empty or at least to the warning light comes on!! It seems OK on long trips as it'll do about 80 miles on a tenner.

Whilst under the bonnet 1 day, I noticed that if I put my hand on the cover of the vacume casing behind the engine that has the throttle body attached to it, there is a sound of air either escaping or being sucked in through the cover. The pitch of the sound gets higher the nearer my hand gets to the cover, then stops as I push down on it. The faster the engine revs the less obvious the sound of air rushing which suggests that something gets bypassed as the engine goes faster, which explains better fuel consumption on longer trips without overdrive. My thoughts are, that more fuel is fed into the engine at low revs because the o2 sensor senses more oxygen due to air getting into the system through the cover but as the engine speeds up something gets bypassed and the sensor adjusts the amount of fuel in relation to air speed and amount. This would also explain why more fuel gets used when in overdrive as the revs are lower. I've put this in so you can all check yours because I think many of you my replace the o2 sensor needlessly (and expensively). The cover has the same amount of oxidisation as all the other ally parts but may be thin and have tiny holes or cracks in. I have put a thick layer of exhaust paste over this cover and will let you know what happens.

The economy light is out and I seem to use more fuel in overdrive. The car has a very strong smell of petrol when starting and the cat smells a bit "eggy" when going up steep hills.

Any way back to the 99 fault code. Does anyone know what this means?

Cheers

Dave

[petroleum]

Are you sure there is a 99 code ? code 31 represents the vacuum sensor signal Make sure the banjo nut is tight and not weeping that connects to the injector rail and also the fuel line hose that is part of it may not be noticed on tick over

[North East Tech]

Hi , if you pull a 99 code up when inspecting the engine for trouble codes it relates to the immobiliser system, basically at some point the car has picked up a fault with communication between the engine ecu and the immobiliser ecu, I would ignore this as it is very common for this to happen.

The Carina runs what is described as a Lean burn engine, and utilises twin ports in the inlet manifold to each cylinder. one of the ports is always open and the other is open is closed unless on full throttle or at motorway speeds. there is a vacuum operated diaphragm in the centre of the inlet manifold which operates the butterflies within the manifold to open and shut the second port and this can sound like its leaking air on idle.

The bulb in your economy light is most likely blown.

The MAF sensor on the bulkhead is most likely the cause of your engine warning light being illuminated.

[Albert kautu]

I have also experienced flash code 99 on my toyota harrier with a broken ignition key chip . I cant start without the chip. How do I get another new key with chip and reprogram it 

[FROSTYBALLS]

Go to an auto locksmith.