Kids, cars, flood water & you guessed it! Any mechanics in the house?

OK, son managed to drive through flood water on Friday and I’m guessing it’s done something but I’m not a mechanic, it’ll be in the garage Monday but just wondering if anyone has an informed view on problem.

Car is a 2010 1.2 Vauxhall Corsa petrol

It went through the flood 12-18” water on Friday morning.
Friday night a warning light came on (Yellow car with spanner) that indicates “engine/transmission, electrics” warning (which seems to cover everything but zombies)

Car still drives but loses power on hills and has very little when pulling away.

I’ve had done following.
Lifted bonnet and had a listen to engine at idle - all sounded good no misfire or odd out of sync sound. (Lol)
Took air filter out, it was bone dry.

From my very limited and not a clue knowledge I have decided it’s water in electrics somewhere, if I leave it will it just dry out on its own?

Or will leaving it cause more damage?

As I say, it’ll go to garage Monday but as will all things I keep trying to fix it in my mind now.

Any thoughts anyone?

It really could be - anything.

Do a google search on car type and the problem "water deluge/water spray/flooded" etc - see if anything pops up from a model-specific forum?

You're really lucky that you didn't hydrolock the engine, as that would have destroyed it. The fact that the engine still runs and sounds smooth on tick over rules out water having got sucked up via the air intake.
Electronics and water don't mix, and it sounds like some sensors got a good soaking which didn't respond well to that.
Good luck with getting it sorted.

The loss of power is probably the car going into limp home mode rather than being a symptom of the issue.b
As said, it could be anything.
Know anyone with an OBD reader? If not it will have to be a garage who will charge for the privilege

I'll put a bet on the Cat being damaged and it has gone into limp mode. If all running OK I don't think it will be electrics. Garage will confirm.

Assuming that Vauxhall's ancient engine designs are as "conservative" as always (or were in 2010):
[ignition off] trace the plug leads back to the distributor cap - remove any easily-shifted impediments to access (air filter housing, plastic cowlings etc) if such exist.
The cap is probably held in place by a couple of clips, unclip and remove - but don't remove plug leads unless you label which is what!
Get some clean paper towel and carefully and thoroughly wipe out the cap and also the rotor which will remain on the engine.
A blast of WD40 inside cap, contacts and rotor can be helpful - which again should be wiped out - and there's a fair chance you'll be up and running again.

WD40 is your friend. WD = water displacement. Spray in and around any plugs/connections/ECUs which may have got wet. Open and close plugs if possible and spray those. WD40 was used for power boat racers. Did you lift the air filter out of the box as they can hold water in the fins.

Sounds like the car has gone into limp home mode, my guess is that water has affected a sensor. Possibly the cat converter has been affected. A garage with a fault code reader will get to the bottom if it quickly.

Drying out the distributer won’t help, if it was that simple the car wouldn’t start.

Driving through flood water in a car us risky, hopefully lessons will be learned.

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Originally Posted by earlofsodbury

Assuming that Vauxhall's ancient engine designs are as "conservative" as always (or were in 2010):
[ignition off] trace the plug leads back to the distributor cap - remove any easily-shifted impediments to access (air filter housing, plastic cowlings etc) if such exist.
The cap is probably held in place by a couple of clips, unclip and remove - but don't remove plug leads unless you label which is what!
Get some clean paper towel and carefully and thoroughly wipe out the cap and also the rotor which will remain on the engine.
A blast of WD40 inside cap, contacts and rotor can be helpful - which again should be wiped out - and there's a fair chance you'll be up and running again.

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I think its a2010 vehicle not 1910 ?..

Disconnect one of the battery terminals for a couple of minutes Take it for a drive and see if it comes back on.

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Originally Posted by deejay

I'll put a bet on the Cat being damaged and it has gone into limp mode. If all running OK I don't think it will be electrics. Garage will confirm.

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Or the lambda sensor under the car (related with the cat). Big chance it got wet and is now 'confused'.

This sort of problems (after driving through water) is a big chance for the garage to offer you a hefty bill... As long as it goes, I would suggest that you ask for a second opinion when the initial price quote is too high.

I know you said the air filter was dry, but I'd try disconnecting the maf (assuming it has one) and take the car for a spin.

It costs nothing to do, and it may rule out one potential source of the problem.

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Originally Posted by meridian

I think its a2010 vehicle not 1910 ?..

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While you're probably right, you've evidently not owned a Vauxhall!

A few years ago I drowned a Nissan Primera in a hidden lake under a railway bridge in the small wee hours- assuming something beyond my ministrations was dead, I called out the AA - who removed some plastic engine cowling, popped the distributor cap off, and had the engine running in moments. After that humiliation, I tend to expect the unexpected - certainly worth checking.

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Originally Posted by walkerwek1958

Driving through flood water in a car us risky, hopefully lessons will be learned.

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Okay boomer.

It’ll dry out in a bit

Put it in a bag of rice.

Quote:

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Originally Posted by deejay

I'll put a bet on the Cat being damaged and it has gone into limp mode. If all running OK I don't think it will be electrics. Garage will confirm.

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This or possibly the O2 sensor which normally plugs into the exhaust. If this has been drowned the engine CpU will be unable to get the mixture right, which explains why it's sluggish under load.

Hopefully £100 will sort it out.

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Originally Posted by Kingstepper

Put it in a bag of rice.

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Indeed. The rice will attract orientals who are in turn good at fixing things.

get the DTC codes read , otherwise you are guessing and may be doing work/ replacing parts not related to the issue .

O2 sensors and crank position sensors are usually low down....poss one of these or the multiplug has got a bit wet.

My money's on a slightly bent rod

Sent from my Moto G (5S) using TZ-UK mobile app

Quote:

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Originally Posted by earlofsodbury

While you're probably right, you've evidently not owned a Vauxhall!

A few years ago I drowned a Nissan Primera in a hidden lake under a railway bridge in the small wee hours- assuming something beyond my ministrations was dead, I called out the AA - who removed some plastic engine cowling, popped the distributor cap off, and had the engine running in moments. After that humiliation, I tend to expect the unexpected - certainly worth checking.

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Sigh.

I suspect that once fully dried out it will be fine.

Pete

Quote:

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Originally Posted by Andyg

This or possibly the O2 sensor which normally plugs into the exhaust. If this has been drowned the engine CpU will be unable to get the mixture right, which explains why it's sluggish under load.

Hopefully £100 will sort it out.

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You know that without seeing the car, I'm impressed.

Most production cars employ a strategy where if there is a Lambda fault of the readings don't make sense, they default Lambda1

Check oil is ok and not going light brown and frothy and you'll be ok engine wise
avoid hills and drive it so the CAt gets some decent heat into it.- heat will dry out most of the sensors

we had some floods and the local ambulances went out to aid stranded people randomly falling off bikes etc..
they were brand new VW's (merc built) and for some reason those engines let water into them and ruined them
full rebuilds needed - just a few inches of water too

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Originally Posted by walkerwek1958

Driving through flood water in a car us risky, hopefully lessons will be learned.

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Yes Dad.

I'm guessing water in the ECU connections. Pop them out and see if they're wet.

I drove through floodwater recently, a local spot that always floods in heavy rain. Having seen the car in front get through I decided I’d be OK, got into the middle of the road and changed into 2nd gear to keep revs high and minimise risk of water getting into the exhaust. Got through it OK but heard a strange noise afterwards that went away and didn’t persist.

Drove over a speed hump next day and the strange noise returned, turned out that the exhaust heatshield was hanging down, having come adrift at one corner. Managed to fix it easily even though it was slightly bent, but I can’t understand why it came adrift when I drove through the water.

Have to admit the water was deeper than I thought and on reflection I should’ve turned round, I’ve been driving since 1975 and I’ve come across floodwater several times, so I know it can be hazardous and judgement has to be used. That’s what prompted my comments, young drivers don’t have the experience and its important to learn.

Quote:

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Originally Posted by walkerwek1958

I drove through floodwater recently, a local spot that always floods in heavy rain. Having seen the car in front get through I decided I’d be OK, got into the middle of the road and changed into 2nd gear to keep revs high and minimise risk of water getting into the exhaust. Got through it OK but heard a strange noise afterwards that went away and didn’t persist.

Drove over a speed hump next day and the strange noise returned, turned out that the exhaust heatshield was hanging down, having come adrift at one corner. Managed to fix it easily even though it was slightly bent, but I can’t understand why it came adrift when I drove through the water.

Have to admit the water was deeper than I thought and on reflection I should’ve turned round, I’ve been driving since 1975 and I’ve come across floodwater several times, so I know it can be hazardous and judgement has to be used. That’s what prompted my comments, young drivers don’t have the experience and its important to learn.

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Driving through flood water in a car us risky, hopefully lessons will be learned.

There’s a busy road near us that regularly floods. When the water level drops, there are often bits of number plates, plastic and metal undershields etc left behind. People don’t realise how much damage driving through water can do physically, even if all seems well with the engine etc.

Pete