Lamborghini V10 and V12 Engines -- Two Engines
One of the often overlooked features when it comes to detecting engine
faults with later Lamborghini engines is the fact that they are really
two engines in one. The front "Check Engine Lights" have a (L)
Left and (R) Right lamp. This not only means that if there is a
localized fault with the engine you can determine on which bank of
cylinders it resides on, but you can further localize the fault by
switching components from one side to the next.
There are 10 or 12 of then in the recent cars. A bad injector can
give rise to a number of check engine warnings. A bad "stuck on"
injector will pump excess fuel into a cylinder causing an engine
misfire, trip the check engine light and cause an OBDII code of 1303
(and perhaps others) to appear. Please see "OBDII Codes" and
"Injector Repairs" for more information on this topic. If
you suspect a faulty fuel injector - it sounds strange - switch it to
the other side of the engine. Then see if the check engine light
changes sides also.
You will need a handheld OBDII reader to reset the engine check codes
first. Remember the ignition should be on but the engine not yet started
before clearing the codes. Then you can start the engine.
A faulty plug is usually apparent by just looking at it. If it is
pitted up it can be corrected by simple cleaning and adjusting the spark
gap if necessary. One fouled plug alone often indicates a cylinder
oil leak or a bad valve. Nevertheless if you suspect a plug switch
it from one side to another. See if the check engine light changes sides
also. To state the obvious - take care not to switch the spark
plug wires themselves!
Spark Plug Coils
In the recent cars (Diablo 6.0L and later) each plug has its own
spark coil. These are known as "Coils on Plugs" or COPs. While they are
quite reliable and efficient if they go they are difficult to test. The
coils are buried deep in the engine directly over the plugs. For this
reason a hand held COP tester cannot get to them. Again switch a
suspected coil from side to side as above to determine if one is at
fault. See more on
Spark plug coil repairs for more info. On the older
cars the coils are away from the engines. Switching is probably not an
Engine Misfire Sensors
There are two engine misfire sensors on later Diablo's. (I do not
know about the more recent cars). Please see the Engine Misfire Sensor
Repairs for more information about these units. If you suspect one is
tripping the check engine light try switching them from side to side.
Again reset the engine codes first. See
Repair Misfire sensors
for more information.
Lamborghini "LIE" Computer
This is the brain of the car engine. It is situated behind the
seat for Diablo's. Again it is really two identical computer boards (each
in its own sealed box) sitting one beside the other. One computer for
the left hand side of the engine, the other for the right. The left hand
computer seems to have a few leftover responsibilities that the right
does not do. For example controlling the Carter motor. However the other
board appears capable of doing this if switched.
Each LIE computer box has two connectors. One pair is yellow colored.
The other white. These connections (at least in Diablo's) can be switched
if you again suspect a fault with a LIE board. The only thing different
here is that the battery power kill switch must first be opened before
switching. Again reset codes before starting the car. Take care messing
with the $5000+ LIE computer in these cars is not for the faint hearted.
However it does illustrate how wonderfully symmetrical the engine is in