Mk 3 galaxy 2.0 diesel - Limp mode

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Wed 4 Dec 2024 18:12
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Hi, wife has got a galaxy mk3. Starts up in the morning and drives, after about 100mettes goes into limp mode. Stop the car, turn off and restart and is fine the rest of the day. Next day exactly the same. Only seemed to start with the recent cold mornings. Any clues before getting it diagnosed. Thanks for any ideas. Sparky 100.
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Wed 4 Dec 2024 18:20
Mk 3 galaxy 2.0 diesel - Limp mode - pd

Yes, get it plugged in and read the codes!

There is no other way of starting to diagnose it to be honest.

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Wed 4 Dec 2024 18:30
Mk 3 galaxy 2.0 diesel - Limp mode - elekie&a/c doctor
When did the fuel filter last get replaced?
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Thu 5 Dec 2024 10:15
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Hi, to be honest i haven’t done that, weather it was done by a previous owner I don’t know. If it was the filter wouldn’t it be hard to start first thing. Sparky 100
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Thu 5 Dec 2024 11:59
Mk 3 galaxy 2.0 diesel - Limp mode - elekie&a/c doctor
I’ve had previous issues with these Psa engines cutting out , and very often fixed by replacing the diesel filter .
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Thu 5 Dec 2024 17:13
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Hi, it hasn’t cut yet but hasn’t got much power but soon as you switch off and switch on it seems to be ok. Would a blocked filter throw up a fault code. Runs fine for the rest of the day it’s only in the morning It plays up. Sparky 100.
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Thu 5 Dec 2024 18:05
Mk 3 galaxy 2.0 diesel - Limp mode - elekie&a/c doctor
May throw a code for low fuel pressure, but you’ll need to check the system.
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Thu 5 Dec 2024 18:41
Mk 3 galaxy 2.0 diesel - Limp mode - gordonbennet

Changing the fuel filter on a Diesel is always a good first move, costs very little especially if you DIY.

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Thu 5 Dec 2024 20:57
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Thanks for that. I will give it a go. It’s just done 50000 miles so could be the original filter. Sparky 100.
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Thu 5 Dec 2024 21:20
Mk 3 galaxy 2.0 diesel - Limp mode - elekie&a/c doctor
Make sure the filter housing is full of fuel when replacing the filter , otherwise you’ll struggle to get it started.
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Fri 6 Dec 2024 13:59
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Ok I will do that and put a primer pump on the return pipe.
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Wed 18 Dec 2024 20:09
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Hi, yes just changed fuel filter but doesn’t seem to change anything.
It seems funny that it plays up first thing in the morning and particularly if it is a cold morning and the rest of the day it’s fine. No lights up. Weird. Sparky 100
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Wed 18 Dec 2024 21:00
Mk 3 galaxy 2.0 diesel - Limp mode - elekie&a/c doctor
I would check the coolant temp sensor on live data to see if it matches actual temperature of the engine. It won’t flag a fault because the engine ecu doesn’t see it as a failure. Remember, computers are clever , but they have no brain .
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Thu 19 Dec 2024 17:39
Mk 3 galaxy 2.0 diesel - Limp mode - sparky100
Hi, thanks for the replies, if the temp sensor was faulty and sent a wrong message to the ecu what would that do, does it change the fuel injection system to throw into limp mode or something else. Sorry about all the questions but would like to know. Sparky100.
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Thu 19 Dec 2024 18:13
Mk 3 galaxy 2.0 diesel - Limp mode - elekie&a/c doctor
Yes , wrong temperature info sent to the ecu will alter the fuelling strategy. Certainly worth checking.
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Fri 20 Dec 2024 12:01
Mk 3 galaxy 2.0 diesel - Limp mode - Simoncelli58

Stop this random checking of stuff.

As much fun as it is, it's almost impossible on modern stuff.

I've seen people replace a good sensor, with a cheap, useless sensor, doubling the fault!

Get it plugged in.

It'll work out cheaper in the long run.

Edited by mickyh7 on 20/12/2024 at 14:17

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