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Hi
This car had a cambelt, balance shaft belt and waterpump replaced in mid-February by a reputable operation.
Two weeks later I noticed it had become slightly hesitant to start when the engine was hot, the engine needed to be cranked over for 3 or 4 sec’s, while prior to that it would start instantly.
A couple of weeks later (mid-march) the car failed to start, I waited 5 minutes, tried again and after the 3rd attempt it fired, all be it reluctantly, the engine check light also came on. Drove car home and checked codes, P0335 Crankshaft Position Sensor “A” Circuit, was the code displayed. The business that had changed the cambelt, checked things out and replaced this sensor.
However the hot starting problem has remained and become more frequent and worse and it now sometimes occurs when the engine is cold (sometimes it starts normally when the engine is cold).
Saturday before last, I took this car for a 400km trip and just after the half-way point the engine stalled while travelling at highway speed, I left the clutch engaged and after about 15 sec’s the engine fired again and seemed to perform normally for the remainder of the trip home. The engine check light did not come on.
On Sunday on the motorway this happened again, but it was worse, in that the stall lasted longer, absolutely no power, pulled off motorway and stopped, the engine remained running until shut down, no engine check light, couldn’t get it started, eventually after 20 minutes was able to get it to start after banging the bottom of fuel tank (may have been coincidence). Check engine light was on at that stage, same code as before but I think I probably triggered it on this occasion while checking plug connections. It drove normally the next 7 or 8 km to my destination, where the car was left for about 6 hours. For the drive home (about 20km) I stayed of the motorway and it stalled twice in similar fashion again about mid-way thru that journey, I was able to use my momentum to “drive thru“ this and kept going.
When this happens it’s not a misfire, it seems to be a total stall with absolutely no power, the car shudders similar to if it’s being bunny hopped.
Haven’t been able to find anything obvious under the bonnet, nor working thru the service manual, is this a faulty fuel pump/filter, pressure regulator or something else???
Just an observation when the engine has stalled it’s been when I have been feathering or just slightly lifting of accelerator.

It really could be a number of things causing this fault. The likely causes are as follows: Cam timing not correct, crank sensor faulty, crank sensor reluctor plate (pick up plate) damaged or keyway worn which will cause it to move, or there could be a wiring problem.

A fuel pump problem will normaly result in loss of power then cutting out but it's definitely worth checking the fuel pressure to eliminate the possibilities.

Check whether the correct heat range spark plugs are fitted to the engine.

If the cam timing was out would that not be noticeable all the time?
The car seems to run and sound normal and have plenty of power, it runs as it did prior to having the cambelt changed, other than the issues described.
Something I have started wondering about today is the possibility that the “stalls” may have occurred when the mivec is dropping back to low speed mode, are the any known issues here?
I changed the plugs myself 2 months prior to the cambelt work, mitsy spec plugs, same brand and designation as what was in car, gap was checked carefully and was to spec, I wasn’t going to alter that anyway.

Thanks

The older MIVEC systems had alot of problems but it didn't normally relate to stalling issues and we are not aware of problems with the 2006 models.