our workhorse

Our work horse or one of them
Hameg 407 semi  digital unit that allows control by a laptop
40mhz bandwidth   and a fast sample rate allowing  capture of certain hard  to  trace events
remember an oscilloscope  is a basically an advanced voltmeter graphing  volts over time
An oscilloscope can capture an event measured nano seconds,a typical cylinder  spark lasts 2 milliseconds so  the oscilloscope allows you to   delve into that  2 millisecond event


Tel:07891903013

We cant find anything wrong with it!!!!!!!!

The classic  phrase from your local spanner monkeys.
Clearly they are wrong since you drive the  car and know it like the back of your hand.
Adding to the above driving a car is a complex experience and your perceptions of how it feels and runs are affected by your mood stress and other manner of factors.
A more rational  approach is how the car performs  ie its behaviour in different gears.
You communicate with  the car through the car through the engine,in fact the  car is simply a box with an engine.
So if the  engine is corrupting that communication then the whole  experience of driving the car is corrupted


Tel:07891903013

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

Is the mixture correct

Air fuel mixture  ratio in a petrol engine  is 14:1 or 14 parts air to 1 part petrol.
Is this an absolute rule yes and no.Sometimes  say under load your engine needs a richer mixture say under full throttle but overall it needs 14:1
An oscilloscope  connected to the secondary ignition can see the  mixture by  the amount of voltage in KV needed to fire the  cylinder
Remember this  is independent of   sensors and ecus or live data making  it a very powerful tool
here comes the rub  effort is needed to put an interpretation  on the waveform it wont tell you

Tel:07891903013

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

Oscillocope channels

The shot below  is showing two oscilloscope channels allowing the outputs of two sensors to be compared,especially useful in the case of cam and crankshaft sensors

Tel:07891903013

Engine fault diagnostics sheffield

We cover all of south Yorkshire and will  go further  afield if work  or a particular job warrants it.
We prefer to work in Sheffield the place we know
Remember if your car isn't feeling  right or not running correctly you are the best  person as the driver to make a judgement,don't let some tell  you  your imagining it,this  is akin to another person telling the pain you have from hitting your thumb with that big hammer is nothing.......... just bite your tongue

Tel:07891903013

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

well thats stupid

running out of petrol and wondering why the car wont start
This sounds ridiculous but we have had just that.An injection   systems needs a certain amount of fuel in the tank to maintain pressure.
Back in the days of carburettor cars   a  third full float chamber would you that extra  fraction of a mile,not so so injection systems.
Always keep your tank at least  quarter full with an injection system

Tel:07891903013

ECU nailed

Vauxhauls have a very stupid design flaw with  the z19xe engine namely the ecu is strapped to the engine which is subject to heat and vibration.
This engine was fitted   to several vauxhaul cars  so if this engine presents itself with certain conditions the ecu is always the no1 suspect.
In fact most  of these  ECU engined cars are in the scrapyard because of this fault

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

Some problems cant be fixed

A car over a certain age or mileage will reach a point  where it isn't worth   throwing any more  money at it.
Its the time to get scenario.Cars are money pits at the best of times.However people get attached to their cars so its usually somebody else to knock them back into the real world

Your alternator

Everybody knows  a car as a generator or dynamo as they were known.
Alternators can   produce a situation that doesn't affect   starting etc but will  alter the way your engine electronics function.
We always test for these conditions as part of our diagnostics procedures,not saying to much  for the competition will be earwigging but suffice to say  your alternators function plays a large part in your engines electronics

Tel:07891903013




lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

loop states

When you start your from cold the engines computer is using a lot of its built in maps until  the O2 sensor and catalytic converter reach operating temperature.
Until then  the computer will  use its default values to some extent,and not apply any fuel trims to the system.

If you are in Sheffield and need   a hand with your engines running state let us know
Tel:07891903013

lunar auto diagnostics

Digital multi meters

A classic multimeter must have  an input impedance of ten megohms to avoid damaging the ecu that deals in very small  currents.
Most meters are 10 but it is  necessary to check before you start prodding about  and messing things up

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

Automotive engine diagnostics sheffield

Automotive engine diagnostics Sheffield is our second name
We offer  full diagnostic services throughout Sheffield so if you have a BMW or a Nissan micra give us a try.
Remember throwing parts at a problem trying  to solve  it never works.If your garage as started mumbling new item  at £300 then its time to walk away from them
Many problems can be solved with simple  solutions ie re wiring or  cleaning of a component an airflow meter or  an ABS brake sensor

Tel.07891903013

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

Never let a garage do it

If you have had your car into a garage and the possibility of a new ECU starts creeping into the picture then they are simply guessing or using the  swap parts scenario in the vain hope of correcting the problem.
This practice can quickly spiral out of control and give you  big  bills and big headaches.
There are a few out there who  understand test equipment and its capabilities,we do and can pursue a fault  using intuition and imagination
So if you are in Sheffield/Rotherham we can cater for all  your needs   regarding  engine fault diagnosis

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

It will cost you a lot more

It is tempting to ignore an engine light if it isn't affecting your engines running to much
It is expensive to run a car at the best of times let alone having to pay out £40 pounds to find out why a fault light as appeared.
The rule with engine problems id a little fault can escalate into a big fault and an expensive one very quickly.

lunar auto diagnostics website


lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

the code is just part of the story

A diagnostic code is just the beginning.
A code  stating  a sensor is at fault doesn't instantly mean the sensor is at fault.
Wiring condition whether it be chafed  broken or simply  the resistance as become excessive

live data from a 2001 volkswagon polo

This is snapshot of data from a 2001 polo  no symptoms just a check that all is in specification
we carry out these  checks to ensure the engine isn't struggling or heading foe either a pending code or a code that will illuminate the dash board MIL light
This car uses a wideband fuel sensor that gives you a far better  determination of mixture strength
Oxygen sensor current is the line to look for measured in milliamps

vauxhall zafira adventures

we have a vauixhall zafira with  a po170 trouble code and two pending
the engine is to put i mildly jumping and  running poorly
Live data  a maf rate at ridiculous levels  but its actual values from the oscilloscope are fine.
Two pending codes are p1555 and po13o.
po1390 is going to be bad wiring to the ECU and  p1555 carboned up  throttle body
This is ongoing so we will keep you in the picture

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

wideband oxygen sensors

A wideband o2 sensor allows for much more accurate  fuel sensing for the  ecu.
wb sensors produce a signal up to five volts unlike standard  o2 sensors that only  reach 1v.
we will have a good look a diagnosing wb sensors at a later  date using live data  graphs directly from the software we use to monitor them

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lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq

MAF meter

Waveform  produced by an airflow  sensor.These sensors measure the amount of air entering your engine and are vital to the engine running correctly.
The sensor  produces a voltages that varies   airflow shown here on an oscilloscope.Starting at .5 volts the the engine revved giving 4 volts.The shape of the waveform  is the key,a peak followed by a drop as the engine  slows down

 

Tel:07891903013

A correct maf sensor  waveform

lunar auto diagnostics

Full range of engine fault diagnostic services Contact us for help

125,east bawtry road
Rotherham
south Yorkshire
s60 4lq