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Robert, UK Qualified Car Technician
Category: Car
Satisfied Customers: 4709
Experience:  Fully qualified / self employed garage technician in the UK
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My 52 plate zafira turns over but doesn't start any idea

Customer Question

My 52 plate zafira turns over but doesn't start any idea
Submitted: 2 years ago.
Category: Car
Expert:  Robert replied 2 years ago.
What engine does it have?
Any warning lights up on the dash ie: - car/spanner or engine light?
Does the engine spin over faster than it did previously?
Have you tried the spare key?
Customer: replied 2 years ago.
Have tried spare key,and it just cranks same as usual z18xe
Customer: replied 2 years ago.
Engine management light on but it o2 sensor
Expert:  Robert replied 2 years ago.
An 02,Lambda sensor fault shouldnt stop the car from starting to be honest,unless the exhaust is restricted creating excessive back possible idea,when its turning over feel over the tail pipe and ensure you can feel some flow out the back -
You need to check to see if its still has spark at the you'll need to test there is spark from the coil pack..if no spark is present it fairly likely the crank,cam position sensor is can double check that on scan and see if rpm signal is seen or not from the crank sensor - Have you checked for fuel pressure or the fuel pumps does actually prime up,you should hear it do that once the ignition is can also check that by checking for pressure at the fuel rail,normally you need a guage to check the pressure..there should be shrader valve on the side of the rail..depress the valve with small screw driver and see if fuel comes out..if not..then you need to get a guage on the rail and check for the possiblity of defect fuel pump...also routine check of failed timing belt will also need to be ruled out..check that cams do still rotate when the ignition is turned..if they dont then the timing belt has gone and will require top end rebuild along with a new belt kit...Have you tried a some starter fluid up into the intake? that might rule out a ignition fault and confirm a fuel delivery issue.immobliser problem
Customer: replied 2 years ago.
Been told could be problem with ecu unit ??
Expert:  Robert replied 2 years ago.
An ecu unit fault would likely show more than just an O2 sensor fault..Id certainly get second opinion or further testing on Tech 2 diagnostics to confirm on that if i where you - there are places you may already know off such a ( bba-reman / ecu testing ) online you can send the unti off to for testing or repair..and that would save a whole load of hassle of reprogramming/immobliser re prgramming..second hand ecu's wont ecus would require TECH2 diagnostic's to reflash/programme..thats why its better to have the one in the car sent of for testing..
Customer: replied 2 years ago.
Could it be immobilser checked everything else,and if it is what do I do to.
Expert:  Robert replied 2 years ago.
Immobiliser would show a flashing car/spanner on the dash - it would also show mulitple codes depending on which area of the immobliser is at fault..the most common faults seen are P1612 P1614 and P1616 it would also show up certain B-codes - You dont appear to mention either of the codes present bar the O2 sensor which i mentioned wouldnt stop the car from starting and id imagine thats already been checked.. theres nothing you can do on a DIY bases you need to check using the proper vauxhall tech2 to see if the immobliser system is deactivated or not.the keys are recognised.the reader works.and the CIM isnt at fault.or as mentioned the fault isnt internal of the ECU presence on the scanner would prove this ither way.leading to as mentioned above the unit sent off for further testing..
Customer: replied 2 years ago.
Tested everything you said I replaced crankshaft sensor,there's nothing wrong with timing belt,fuel at rail so its ether ecu unit or immobiliser what do you think
Customer: replied 2 years ago.
If I took another ecu unit and immobiliser and keys would they work on my car
Expert:  Robert replied 2 years ago.
They might but you would to code it in for the CIM and that can only be done by Tech2 as mentioned before - If the ecu is at fault or suspect then get it tested or sent off first..replacing all that above often 50-50 seen it before.and you need the seurity code from donor car anyway..have you tried a extra earth on the ecu body..seem to remember a few ecus needing that..might be worth trying..but as upto now you would someone with higher end scanner to see exactly whether its immobiliser or not..