A610 Cutting out problem

I had an interesting conversation with a chap called Jon Butterworth who came to the southern meeting on Monday for the first time. He has a red 610 that was suffering from the cutting out issue and had been in & out of the main dealer for years with previous owners to no avail. Eventually he was presented with some evidence that this problem was known to Renault and an uprated TDC sensor with improved heat shielding specified as the fix. This was specified during the GTA production run but now I'm wondering if the 610 problems relate to either failing heat shielding (mine only cut out on incredibly hot days when stuck in traffic) or possibly is it the case that the incorrect TDC sensors have been fitted to cars down the years - perhaps by people assuming the sensor from another PRV engined car would suffice? Anyway, there's some very interesting correspondence & confirmation that people were using the earth bypass strap 20 years ago! The uprated TDC sensor has a specific part number and it's shown in the attachments. Surely worth starting here if your car has this problem.

A610 cutting out 2.jpg

A610 cutting out 3.jpg

[phildini]

Top right of document it says D50 1/2 not 3 so its not a 610 problem as discussed on Monday. The 610 TDC is wired completely different from a GTA, it's the GTA that had the problam as the the TDC sensor wire run so close to the turbo.

As I said in my post, this fix was specified for the GTA, but it highlights that this sensor if faulty causes the earth to be cut to the fuel pump. Replacing the sensor on Jon's car with the correct item has fixed his so it's surely got to be one of the first measures taken before hot wiring the fuel pump for any 610 with problems. Maybe I'm wrong, but from what I've seen on the forum so far, the TDC sensor has been discounted as the cause of the problem. It may not be the only cause, but here's clear proof that it can be the problem.

[mettersl]

TDC sensor in the A610 sits under a heat shield, on mine the welding had corroded and separated into two bits, so I had to re weld it and put it back in place.
I wonder how many other cars have this, but are unaware, its not really visible, I had to remove and replace by touch alone in the car.
Its certainly one of those things to look for if you want to keep the car reliable,

As I said in my post, this fix was specified for the GTA, but it highlights that this sensor if faulty causes the earth to be cut to the fuel pump.

Apologise for not picking up this post when it was written, but I feel that the above should be clarified. It is quite possible that if the TDC sensor is faulty it COULD cause the fuel pump to fail.... BUT, the TDC's sensors main function is to provide a pulse/signal to control the injection/ignition. What must be remembered in the case of these 610's, is that once the engine stops, by energising the fuel pump relay locally, the engine then starts and continues to run without further failure pointing to the fact that the TDC sensor is still working as the injection/ignition continues to work.
The Renault Technical Note is certainly interesting when it comes to the early GTA's pre 1989 (note dated April 1989) and is something I am logging in my filing cabinet under my hat, but the 610's first came out in 1991 and I am sure Renault being aware of this early GTA problem would not have repeated it in the 610's.

...but from what I've seen on the forum so far, the TDC sensor has been discounted as the cause of the problem. It may not be the only cause, but here's clear proof that it can be the problem.

The reason it has been discounted in these 610's is because of what I have written above. The signal from the sensor enters the ECU and, as I say, goes to control the inj/ign, it may also, within the ECU, branch off to another part of the circuit to operate the fuel pump relay..... this, of course is an assumption, but a reasonable one, as, without a circuit diagram of the ECU, it is really impossible to be sure.
Please don't let this explanation stop any comments or ideas about this 610 problem, any ideas are welcome as they might trigger a new line of thought on this elusive fault.

John