406oc.co.uk

As I'm sure lots of you know I have a 2002 vintage with the fairly rocking-horse-poo-esque 2.0l HPi direct injection petrol engine.

It's got the naughty light on again, accompanied with the "Antipolution System Defective" message haven't had that for ages either!!

The code is P1416 which my budget scantool software says is a "Manufacturer specific code, please refer to your vehicle's manual"

A bit of googling reveals. "P1416 Port air circuit Malfunction / Air system bank 2 / EDC15C2-Converter downstream temperature" Splendid! Can anyone tell me what that means and what I can do about it?

Clearing the codes does sometimes get rid of it, but it's always back within a start or two.

I just Googled the code, first result is this: http://www.c5forum.com/cgi-bin/ultimate ... /4740.html C5? No, not a Citroen

I'm think it's either got exhaust port air injection or it's a generic code and means eff all. What happened to that HPi howthebluddyhelldoesthiswork link?

Yeah I got all the dodgy Chevy links first too, then I got the Pug and Shitroen codes.

Converter - Downstream Temp is the Lambda sensor 'after' the CAT (you must have two, one upstream, one down) and they talk to each other! any value outside of the norm will flag a fault.

Cheap petrol and short runs can bring about this problem.

I don't know what the other stuff means though but the 406 isn't exactly forthcoming with clues is it?

The fool inside me would be tempted to slosh in a bottle of Wynne's Inj cleaner and go for an Italian but the good guy is saying "ooh, what about that expensive HP pump? it might not like it?"

I don't know how you'd get it confirmed that one (or both) the CAT sensors are duff but you could start by enquiring about the price of them? you might need an eggsauce place to fit them cos they'll be well stuck in there (although a hot torch is normally all they'd use) The electrical plug for the sensors can be under the handbrake/carpet area just to add to the fun.

Just be careful though Dai as it could become a wild goose chase........

Australia didn't get the HPi engines in both the C5 and 406...

That said, I would be looking at a sensor issue. Anti Pollution Faults are common in Australia due to the humidity and potential for condensation mucking things up!

OK so I know I've been a long time getting this sorted, I hang my head in shame

Anyway I eventually got 'round to taking it to the independant specialist last week and his computer diagnosed the fault as

Permanent fault. Catalytic converter downstream temperature sensor. Short circuit to positive or open circuit.

Interestingly their computer reads the code as P1419, not P1416 as mine said...

The guy showed me the sensor, although it's "downstream" it's actually pre-cat, you reach it down the back of the engine but I'd have to look again to see whether it's on the manifold or the downpipe. So after a short discussion on the reliability of diagnosing "sensor faults", coupled with the fact that it looked difficult to reach and was probably siezed solid I booked it in for this morning.

Here's the culprit


So that's £35.25 for diagnostics last week, £104.19 for the sensor and half an hours labour to fit (£23), = £162.44 inc vat, all for the pleasure of extinguishing a little light and stopping the car from beeping at me several times a day.

Still I'm so glad to have it sorted.

Glad you got it sorted Dai, pity about the cost, I had an expensive day yesterday...the exhaust fell off my Expert van...£100 for parts.

no welder jasp?

I don't get involved with welding.They always break in a bad spot on these Experts.You have to chop it in pieces to remove it.

ps, I priced up a Lambda sensor for a Mazda MX5 today, got lots of differing prices, £135+vat the most expensive, £35+plus vat for a Bosch one at Andrew Page the cheapest....guess which one I ordered?

What was the fault of this dai? whereabouts is it? im thinking i have the same fault!!

Just the naughty light and the antipollution message mate, didn't notice any other symptoms...

It's down the back of the engine mate, ether on the exhaust manifold or the downpipe, I can't remember . Never had limp mode though so I doubt it's the same problem that you've got

hmm i get all 3... lucky me lol. hopefully gunna get the codes read today after its gone back in for re-mot.