Renault Megane Mk1 not starting
Discussion
Hi guys,
I have a Renault Megane mk1 1.4 16v from 2002.
I can't get it to start. It turns over fine on the starter motor. I have changed the TDC sensor for the improved version. I have replaced the ECU and had a complete data transfer done from old ECU to new by a ECU specialist. I am getting a spark. I am getting fuel to the fuel rail but not past the injectors into the combustion chamber (I'd assume they aren't opening?)
The injector relays seem to be working, so I'd assume it must be some dodgy wiring between the relay and the injectors or back to the ECU?
Any one have any experience with this and can advise me if something else may be the issue?
Thanks in advance.
I have a Renault Megane mk1 1.4 16v from 2002.
I can't get it to start. It turns over fine on the starter motor. I have changed the TDC sensor for the improved version. I have replaced the ECU and had a complete data transfer done from old ECU to new by a ECU specialist. I am getting a spark. I am getting fuel to the fuel rail but not past the injectors into the combustion chamber (I'd assume they aren't opening?)
The injector relays seem to be working, so I'd assume it must be some dodgy wiring between the relay and the injectors or back to the ECU?
Any one have any experience with this and can advise me if something else may be the issue?
Thanks in advance.
Is any fuel at all getting into the cylinders?
Get some NOID lamps and see whether the injectors are being actuated.
If you are familiar with the sound injectors make it is usually possible to hear them while cranking/running. If you aren't familiar with it, try applying 12V across the injector briefly and you should hear a characteristic tap as the injector opens and closes. That would confirm they are all mechanically working. (Seems unlikely that they have all failed at the same time, but it is an easy test and IMO worth doing just as a sanity check.)
Any fault codes? I don't know your ECU, but many OEM ECUs will detect an injector circuit fault.
I assume you have access to the ECU. If you can identify the pin-outs, it is easy to do a continuity test of the injector circuit(s). You can prove you are testing the correct terminals by disconnecting the injectors and confirming you seen an open circuit.
One way to demonstrate that this is an injection side fault is to spray easy start/cold start into the intake while cranking. If it shows any signs of firing that supports the theory that it is lean/dry. If not, maybe it is flooded or you have an ignition fault.
Get some NOID lamps and see whether the injectors are being actuated.
If you are familiar with the sound injectors make it is usually possible to hear them while cranking/running. If you aren't familiar with it, try applying 12V across the injector briefly and you should hear a characteristic tap as the injector opens and closes. That would confirm they are all mechanically working. (Seems unlikely that they have all failed at the same time, but it is an easy test and IMO worth doing just as a sanity check.)
Any fault codes? I don't know your ECU, but many OEM ECUs will detect an injector circuit fault.
I assume you have access to the ECU. If you can identify the pin-outs, it is easy to do a continuity test of the injector circuit(s). You can prove you are testing the correct terminals by disconnecting the injectors and confirming you seen an open circuit.
One way to demonstrate that this is an injection side fault is to spray easy start/cold start into the intake while cranking. If it shows any signs of firing that supports the theory that it is lean/dry. If not, maybe it is flooded or you have an ignition fault.
GreenV8S said:
Is any fuel at all getting into the cylinders?
Get some NOID lamps and see whether the injectors are being actuated.
If you are familiar with the sound injectors make it is usually possible to hear them while cranking/running. If you aren't familiar with it, try applying 12V across the injector briefly and you should hear a characteristic tap as the injector opens and closes. That would confirm they are all mechanically working. (Seems unlikely that they have all failed at the same time, but it is an easy test and IMO worth doing just as a sanity check.)
Any fault codes? I don't know your ECU, but many OEM ECUs will detect an injector circuit fault.
I assume you have access to the ECU. If you can identify the pin-outs, it is easy to do a continuity test of the injector circuit(s). You can prove you are testing the correct terminals by disconnecting the injectors and confirming you seen an open circuit.
One way to demonstrate that this is an injection side fault is to spray easy start/cold start into the intake while cranking. If it shows any signs of firing that supports the theory that it is lean/dry. If not, maybe it is flooded or you have an ignition fault.
There is no fuel getting to the cylinders.Get some NOID lamps and see whether the injectors are being actuated.
If you are familiar with the sound injectors make it is usually possible to hear them while cranking/running. If you aren't familiar with it, try applying 12V across the injector briefly and you should hear a characteristic tap as the injector opens and closes. That would confirm they are all mechanically working. (Seems unlikely that they have all failed at the same time, but it is an easy test and IMO worth doing just as a sanity check.)
Any fault codes? I don't know your ECU, but many OEM ECUs will detect an injector circuit fault.
I assume you have access to the ECU. If you can identify the pin-outs, it is easy to do a continuity test of the injector circuit(s). You can prove you are testing the correct terminals by disconnecting the injectors and confirming you seen an open circuit.
One way to demonstrate that this is an injection side fault is to spray easy start/cold start into the intake while cranking. If it shows any signs of firing that supports the theory that it is lean/dry. If not, maybe it is flooded or you have an ignition fault.
I don't have access to a fault code reader unfortunately but I will try all you have suggested and see what the outcome is.
Thank you for your help!
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