TD5 misfire in heavy rain

Hello

I have a strange problem that I never thought was an issue with diesel motors. Twice now, in fairly heavy rain, my TD5 has started to lose power and judder badly. It's a similar feeling to a petrol misfire.

It happens at speeds of 65-70Mph or slower if the throttle is pushed a little harder than usual. As I ease off the throttle, the problem disappears.

I wonder if there is rain getting into the engine bay and hitting some connections, but which ones they are, I haven't managed to find. I have noticed that between the wings and the bonnet, there is a moderate gap, so it would seem credible that water is affecting it.

Has anyone else seen this problem? The vehicle's only covered 12,000 miles. It has ABS and traction control, so I guess there's chance it could be related to that but tend to think it's down to loss of power.

Thanks

Matthew

Reply to
Matthew
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|| I wonder if there is rain getting into the engine bay and hitting || some connections, but which ones they are, I haven't managed to || find. I have noticed that between the wings and the bonnet, there || is a moderate gap, so it would seem credible that water is affecting || it. ||

The engine ECU is in the engine bay, under a plastic cover on the offside at the front. Could water be getting in there? Unlikely, but with a diesel, it's the only thing I can think of that might cause these symptoms. I'd be inclined to have a look in there, pull off the connectors and WD40 it.

Reply to
Richard Brookman

In news:bjt0pu$mmrj8$ snipped-for-privacy@ID-108243.news.uni-berlin.de, Richard Brookman wrote: | Matthew wrote: | ||| I wonder if there is rain getting into the engine bay and hitting ||| some connections, but which ones they are, I haven't managed to ||| find. I have noticed that between the wings and the bonnet, there ||| is a moderate gap, so it would seem credible that water is affecting ||| it. ||| | | The engine ECU is in the engine bay, under a plastic cover on the | offside at the front. Could water be getting in there? Unlikely, | but with a diesel, it's the only thing I can think of that might | cause these symptoms. I'd be inclined to have a look in there, pull | off the connectors and WD40 it.

On a Defender the ECU is under the driver's seat.

Matthew, have you tried splashing a hose around the engine bay to see if you can replicate the problem? Take the acoustic cover off the rocker cover first to improve access.

Note that the foam in this cover is NOT waterproof so you don't really want to fill that up!

Mark

Reply to
Mark Pewsey

No, I haven't because the misfire only happens with moderate throttle, such as when I'm trying to keep up a good speed on the motorway for example.

I suppose I could road test it afterwards but since the problem has happened every time I've driven in hard rain, it's conclusive that it's caused by water.

I've been looking at the connectors today. The air flow meter's connector and the air filter assembly connector are quite a long way into the centre of the engine bay, but I suppose it's still possible for water to splash that far.

It would be ideal to seal the bonnet with rubber I would have thought. The anti-lock brake equipment is similarly exposed on the driver's side and you can actually see it with the bonnet closed. I'm surprised that I'm the only one who's had this problem.

Matthew

Reply to
Matthew

In news:bjv3sq$lin$ snipped-for-privacy@hercules.btinternet.com, Matthew wrote: || Matthew, have you tried splashing a hose around the engine bay to || see if you can replicate the problem? | | No, I haven't because the misfire only happens with moderate | throttle, such as when I'm trying to keep up a good speed on the | motorway for example. | | I suppose I could road test it afterwards but since the problem has | happened every time I've driven in hard rain, it's conclusive that | it's caused by water. |

Fair enough - I just thought that judicious use of a hose pipe might mimic the water spray/splash effect of driving at speed. It may be that speed and air flow might be combining to get water into those hard to reach spots.

| I'm surprised that I'm the only one who's had this problem. |

You're not. Been a while since I've seen it mentioned here - has been a reasonably dry summer in the UK, where most contributors seem to live.

Try searching on Google, using the Groups tab, filtering as required.

Good luck!

Mark

Reply to
Mark Pewsey

|| || On a Defender the ECU is under the driver's seat. ||

Oops! He didn't say it was a Defender. I was thinking of where it was on the Disco II, where heavy rain *might* cause those symptoms.

Rich

Reply to
Richard Brookman

Could it be water on your accelorator?

Pete

Reply to
Pete

It's a good point, but not as far as I can tell. There's no leak in the footwell but I did wonder the first time this problem occurred, if there was something wrong with the potentiometer on the throttle.

I can imagine in a few years' time that owners will be having problems with these throttles. They're sure to wear out eventually. Perhaps they're a service item?

Thanks

Matthew

Reply to
Matthew

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