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[downsmen]

Hi just got to work this morning, the car was running like a pig it was really lumpy and complete lack of power.

Called the AA out and he said ( i dont know whats wrong!!! )
Have done paper clip test and come up with the following faults, allthough the AA man said there wasnt any.

12
73
38
31

If any one has any ideas of how to fix this i would be greatfull as the car is unusable at the moment.

[rustym95]

that looks like a cam sensor fail and them are the false numbers 12 is normal, but some one will tell you better, if engine works fine when cold the gose in limp mode (lack of power) any time after start would say cam sensor.

[downsmen]

if this is the cam sensor gone would i be able to drive home or should i get it recovered.

[Jimbob]

ignore cam sensor, they are reliable on v6's

you have 02 sensor and maf codes there...

[rustym95]

if will get you home but wont have the power, as it nocks out the timing. it should get you home ok. in limp home mode.

[Marks DTM Calib]

12 - Start of codes - nothing to worry here
73 - Mass Air Flow Sensor Voltage Low  - Interesting
38 - O2 Sensor 1 Circuit Voltage Low - Probably as a consequence of the fault
31 -Engine no rpm signal - i.e. engine not running

Ok, now the key indicator for me here is the MAF low voltage....and this is hinting at an air leak.....the O2 sensor is also showing a similar result.

I would start by looking at the brake servo pipe for signs of it rubbing though thanks to chaffing on the aircon pipe.....which is due to poor aftermarket workmanship.

If this is ok, start looking around for a leak e.g. is the idle valve fitted correctly etc.

[downsmen]

Okay i shall a look for a air leak, the AA man did say he thought there was a leak it was very noisy.

He found a pipe at the back of the engine which wasnt connected to anything nearby to where the 4 pipes go into the intake.
Is this meant to be connected or is this a breather pipe?

[Jimbob]

Okay i shall a look for a air leak, the AA man did say he thought there was a leak it was very noisy.

He found a pipe at the back of the engine which wasnt connected to anything nearby to where the 4 pipes go into the intake.
Is this meant to be connected or is this a breather pipe?

thats sounds like the auto gearbox breather pipe, and is fine.

[Jimbob]

you can try spraying carb cleaner around the engine to help pinpoint airleak, when it sucks in the vapour, the engine note will change and you now have the approximate area 

[downsmen]

i have looked at the brake servo pipe, it has rubbed on the air con pipe it looks like it has worn but i cant see any obvious hole, but would i see a hole?

also where is idle valve?

[downsmen]

just taken the brake servo pipe of and checked it i see no holes in it  so what do i check next?

the car is now at home after a slow juddering journey

if i cant fix this i might have to take it to the garage  

[djac]

As a temporary measure you could try tightly wrapping the abraded part of the servo pipe with tape, see if this makes any difference. There might be a small pin hole which would be difficult to spot....

[Andy H]

As a temporary measure you could try tightly wrapping the abraded part of the servo pipe with tape, see if this makes any difference. There might be a small pin hole which would be difficult to spot....

If it is the servo pipe then you should be able to check by pressing the worn area with your thumb (with engine running) and hear/feel the air leak.

As you have an error code up for the MAF sensor already is it worth running the engine with the MAF plug disconnected to see if it runs any better in 'limp home mode'? (it might already be in limp home mode so disconnecting might not prove anything)

MAF sensors can fail. I would also check the wiring to the MAF sensor for wear/damage/corrosion

Does it idle OK?

[Entwood]

Have you tried lightly spraying carb cleaner around the area whilst the engine is running ??

Any vac leak will suck in the cleaner and the engine note will change as the cleaner is burned as "extra" fuel for a few seconds... it is a quick and easy way to find air leaks ....   wipe the engine down with paper towel after and you end up with a clean engine as well ..

Jimbob also suggested this but I don't know if you've tried it yet ??

[downsmen]

hi just got back in from the car.
right i have wrapped the worn piece of the pipe with tape and guess what?
No difference
i have also tried spraying some carb cleaner about but cant notice any difference in engine revs.
The engine runs lumpy all the time even on idle.
there is however a really loud sound of air hissing under the black cover thing in the middle of the engine,
is this normal?

Please help i cant drive it like this