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Hi guys, I've recently traded in my 147 for a gorgeous red G, but she has a couple of issues...firstly while driving around the cooling fan is coming on and won't go off ,even while doing 60 on the motorway in 6th. She's done 70k and I'm wondering if it's time for a cam belt change and a new water pump? Or maybe just something simple like a sticking thermostat?? Secondly my rear heated window and led brake light aren't working, any suggestions?

Cheers Zac
 

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cooling fan comes on:

- the dpf is regenerating,
- the aircon is on and the pressure on the high side is above a threshold.
- engine temp is high.

I wonder how you can hearthe fan at 60 though...

regarding faults at rear: broken wiring loom going to the hatch.
 

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Discussion Starter #4
The dpf isn't regenerating at this point, I never use the air con and the engine temp never goes past 90. Know the cooling fan has come on as the mpg drops from around 60-70 down to about 40 and if I pull over then you can hear it. I'll have to check the loom tomorrow then, I'm guessing it normally has problems where it comes from the body to the boot?
 

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MPG drops when the DPF is regenerating! then the cooling fan will be on! There aren't any warning lights to say its regenerating. The only way you'll tell is if you stop & hear the exhaust ticking because its got so hot.
 

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The dpf isn't regenerating at this point, I never use the air con and the engine temp never goes past 90. Know the cooling fan has come on as the mpg drops from around 60-70 down to about 40 and if I pull over then you can hear it. I'll have to check the loom tomorrow then, I'm guessing it normally has problems where it comes from the body to the boot?
definitely the dpf is regenerating at that time... just the cooling fan on has a negligible effect on fuel consumption at 60 mph...

yes, in the rubber boots between body and hatch.
 

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Discussion Starter #7
Surely the dpf shouldn't be regenerating every 100 miles or so though ? Unless it's not completing the cycle? Hopefully when it gets remapped and the dpf removed I should be cured of this problem then
 

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It depends how you drive it, if you are giving the car a bootful quite regularly the engine will be producing soot, which will cause the DPF to fill up and require regenerating.

I have had the odd occasion on mine where the DPF has regenerated at less than 100 mile intervals, especially whilst doing shorter journeys in cold weather. In the summer it seems to regenerate every 300 miles or so.

If you drive at 60mph in 6th you are likely to trigger a regeration if one hasn't happened for a while as that sort of speed gives ideal conditions for it to happen.


Personally I would leave the DPF on, as on the G they rarely give any problems. If you get it removed there is the legal issue and the car is likely to fail it's MOT if the tester is doing their job properly.

It isn't difficult to spot a car without a DPF due to the soot that comes out on acceleration.


If you find which wire is broken in the loom you may be able to splice a new bit in if you are handly with a soldering iron and heatshrink.
 

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As Symon said it's easy to splice another wire in if you can solder (if not have go it isn't that hard if you have patience a steady hand, plenty of Youtube vids these days I bet)!
The temptation will be to cut the rubber to look but if you tug at each wire you can find it and splice it in and return it to stock looking and much neater job! :)
 

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Surely the dpf shouldn't be regenerating every 100 miles or so though ? Unless it's not completing the cycle? Hopefully when it gets remapped and the dpf removed I should be cured of this problem then
Every 100 miles is a lot, but not impossible. How many miles on the car?

If the cycle doesn't complete 5 times in a row, you get a warning light on the dash. So for now let's assume the cycle completes. That would mean your engine is making excessive soot. How is the oil level? very important to see it isn't dropping, or RISING.

a knackered turbo could cause dropping oil levels, and a lot of oil in the dpf triggering a regen.

A faulty EGR valve could cause excessive soot production, as will an injector that's wearing out or is fouled. Worn compression rings aswell.

Oil with a calcium based detergent wil cause less soot production than a magnesium/calcium detergent. That's because calcium acts as an oxidiser helping soot burn completely at lower temperatures. What oil is in there? Sometimes you can find an oil analysis on the net showing the presence of magnesium.

Lastly, the filter could just be full of ash already and would need cleaning or replacing.
 

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forgot to add:

Also check for boost leaks, that could definitely add to soot production.

On the rare occasion I interrupted the regeneration, it doesn't necessarily start again immediately after. The regen is of a fixed duration, but it seems that if the regen finished early you could interrupt the proces and don't get an early regen afterwards.

Last summer my regens were 1000+ miles apart, but this winter I had one regen occur after 150miles. That was when we had -9°C temperatures and I had been warming up the car for 30 minutes before getting in and driving off.

Also, 60 mpg at a steady 60 mph is poor, esp for a 1.6. With a fully warmed up engine at those speeds I'd expect at least 80 mpg, if not close to 100.
 

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.....Also, 60 mpg at a steady 60 mph is poor, esp for a 1.6. With a fully warmed up engine at those speeds I'd expect at least 80 mpg, if not close to 100.
I can't get that, but then bigger wheels, bigger brakes, wider tyres all take their toll. When I had my 2.0JTDm a couple of winters ago, that was regenerating every week (70 miles or so) and that was with V-Power. If I didn't take it on a run at the weekend it would run rough the next week. It was doing 2 x 4 1/2 mile trips per day It wasn't broken, didn't run badly and had about 30,000 on the clock. Come the summer and it was a different story.
 

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it takes a while, but after the engine, gearbox, driveshafts and wheel bearings are fully warm I get very close to 90 MPG at 60 mph.... and this is a 2.0.

My consumption figures going to school (hyundai or mitsubishi technical training, a few miles from each other but 50 miles from home) are up to 80 MPG. the first half is worse, closer to 60 mpg but I make up for that in the second half roughly. I start in the city, and stop at the outskirts of Antwerp.

I'm running 17", brembos, tct (heavier) etc...

had a regen this morning: 552km since last time.
 

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Mine must have something wrong, because at a steady 60mph I average about 55mpg. :lol:

In normal driving I am averaging 42mpg on my 15 mile commute on mixed roads.
 

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But it's flat in Belgium & there are straight roads.
 

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Also more roads per person than just about anywhere else, so not so much stop-start traffic.

I with I could just do a steady speed all the way to work, but it never happens.
 

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Also more roads per person than just about anywhere else, so not so much stop-start traffic.

I with I could just do a steady speed all the way to work, but it never happens.
it doesn't happen for me either. traffic jams start 300 meters from my door.

https://www.youtube.com/watch?v=VeE83F9fwxw

I'm lucky to get 20 mph average over a tankful without motorway driving...
 

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So why such good mpg then??
 
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