Engine warning light

Does anyone know why my engine light comes on when I'm driving my
Vectra 2ltr diesel, but then goes off if i even slightly touch my
brake pedal?
Anyone who can help me, as my Haynes manual has been no help.
Thank you.
Benny

 

What year is it?
If pin 6 of the diagnostic socket is engaged, flash codes can be retrieved.
link to pulling codes:
http://forums.delphiforums.com/cartune/messages?msg=28.1

 

I would be really interested to know the answer to that one
since my problem developed in the same way.
I have a 1999 Vectra diesel and when the engine management
light used to come on whilst driving it would extinguish
upon a light touch of the brake pedal. Not anymore.
After 9 months of this the light now comes on every few
minutes of driving accompanied by a dramatic reduction in
engine power.

The car is now virtually undriveable for more than a few
miles at a time. I am going to try and pull the code/s by the
method that has been described elsewhere on this very useful
forum. Would still appreciate any other advice

 

well it's something pretty serious for hte car to go into 'get you home'
mode.
pull the codes & let us know

mike

 

If I get a chance I'll have a go tomorrow. I hope it's not
something serious. Since the problem has been quite
bad I've still driven the car from London to Cornwall
twice, used it every day and down to Dorset last Saturday
from Kent. The car will get up to 80mph after about 2
minutes, foot flat to the floor, but the light constantly
comes on and goes off during any journey, with a loss
of power. If I allow the revs to drop to around 1500 the
light goes out immediately but comes back on again
past 50mph or during hard acceleration. A real pain
which draws regular abuse from other drivers who
think " that arsehole in front keeps slowing down for
no reason". I was following behind a dustcart the other
day but even that got away from me!

 

had the same problem, it turned out to be the air flow sensor, on the
intake pipe near the air filter, just two screws and a wiring plug to fit, I
had the car put on all the testing gear first and it said it was a different
problem which cost £200. before they found the right thing, hope this
helps,( the part is about £100 sorry) it was a different car to drive
straight away

 

If it goes off when the brake is applied then it is due to bad adjustment of
the brakelight switch. on a diesel the switch is double poled (one set of
contacts on and one off) if the switch is badly adjusted ECU fault codes
this and limp home mode results.

To cure fault drop the cover off above the pedals (three large black plastic
screws) press down on brake pedal and pull switch pin down with pointed nose
pliers release pedal (switch will then ratchet back to correct position) If
fault is still present then switch may be u/s and need replacing


Steve

 

This is greatly appreciated, Steve. I'll check this one out
tomorrow. I tried to pull the codes today with a paperclip
but the management light would not flash. It just went out
as normal, a couple of seconds after the ignition was
switched on.
Checked the terminals on the 16pin socket down by the
handbrake under a plastic cover. Found only number 1
terminal to be live (ignition on or off) found 2 other
terminals, 14 and 15 I think, were earth wires, the others
didn't appear to be either earths or lives?
There is nothing connected in the number 6 pin but
there is a wire connection running to the number 5
terminal however, grounding that one to earth with
the ignition switched on/off caused nothing at all to
happen.
Anyone know what I am overlooking here?

 

Thanks for this. I took the sensor out today and had
a look. It appears to be a fairly basic wire probe in
a sealed plastic case. I wouldn't know how to test it.
I noticed that it's labeled "Bosch" a sort of engineering
"designer label" these days, commonly used to justify rip-off
prices, so £100 for a short piece of wire in moulded plasic
which might originate from China, sounds par for the course.
This is why I am trying to sort out the problem myself.

 

Under no circumstances should the other terminals be probed. If pin 6 is
vacant, a later protocol (EOBD) is used for diagnostics, which requires a
scan tool. All later vehicles are protocoled to EOBD (European on board
diagnostics) with upto 4 possibilities on format. The good news is, there
will soon be an inexpensive reader available on the UK market, allowing
DIYers to read their own codes. One such product is called Autotap, which
plugs in to a laptop.

 

........cut additional very useful information

Thankyou for your reply. As a result I have now found
an auto-electrical diagnostic centre in Bexleyheath Kent
which has agreed to read the code/s for me on Monday
for £20, which is about half of what most others charge.
I will post back with the fault diagnosis which might be
useful to others in the future.

 

Sensible idea.
Please ask them for all the powetrain codes and post them back to us, as a
particular code doesn't necessarily mean it's component is faulty,
especially if more than one code is present.