Engine Management Faulty Warning

Yesterday my C3 beeped and gave me a warning saying the braking system is faulty. This has happened before, but I can't remember how I cured it, the brakes seem fine.

Today however the car beeped again and gave a warning saying the engine management system is faulty.

The throttle suddenly became very sensitive, just a touch on the pedal would send the revs skyward, and the idle speed went up to about 1500.

I managed to drive home 5 miles, with the car driving a bit like a go-kart, but now I'm wondering what I should do? Can I reset the engine management system?

The car is a 59' plate 1360cc Petrol, with 87,000 miles on the clock.

mitchino wrote:Yesterday my C3 beeped and gave me a warning saying the braking system is faulty. This has happened before, but I can't remember how I cured it, the brakes seem fine.

Today however the car beeped again and gave a warning saying the engine management system is faulty.

The throttle suddenly became very sensitive, just a touch on the pedal would send the revs skyward, and the idle speed went up to about 1500.

I managed to drive home 5 miles, with the car driving a bit like a go-kart, but now I'm wondering what I should do? Can I reset the engine management system?

The car is a 59' plate 1360cc Petrol, with 87,000 miles on the clock.

Hi mitchino, my first step for engine problems would be to read the error codes stored in the car with a cheap OBD2 reader from eBay (click here). From this you can see what errors the display is trying to warn you about and any other codes stored.


But, for braking errors its worth getting the car checked professionally because although the braking feels ok, you may have a problem with emergency braking assistance, ABS or an ESP problem that you won't find out until its too late.

I have an OpCom reader for my Vauxhall Zafira, but just discovered that doesn't fit the citroen ecu port.

I haven't got time to wait for an eBay unit to arrive, so need to get one from machine mart/halfords etc - which model will fit the C3 port?

Also discovered that my brake fluid reservoir was extremely low, so I've topped that up. There was also some moisture in the ecu plug in the engine bay- last year the car died on me and I got the RAC out - the guy immediately knew it was moisture in the ecu plug, blasting it with an air gun sorted the problem out. Maybe this is causing ecu problems?

So after topping up the brake fluid and drying out the ecu connector and port, the car seems to be working normally, no beeps so far, idling at 1000 rpm and not revving like crazy at the slightest touch on the accelerator.

Will take it for a test drive and see what happens.

mitchino wrote:I have an OpCom reader for my Vauxhall Zafira, but just discovered that doesn't fit the citroen ecu port.

I haven't got time to wait for an eBay unit to arrive, so need to get one from machine mart/halfords etc - which model will fit the C3 port?

Any generic standard OBD2 reader will fit yours.

mitchino wrote:Also discovered that my brake fluid reservoir was extremely low, so I've topped that up

Keep an eye on that and maybe check the wheel cylinders and calipers, the flexible hoses and brake master cylinder for signs of leaks.

mitchino wrote:There was also some moisture in the ecu plug in the engine bay- last year the car died on me and I got the RAC out - the guy immediately knew it was moisture in the ecu plug, blasting it with an air gun sorted the problem out. Maybe this is causing ecu problems?

Quite possibly. There shouldn't be any moisture in there, so you may have problems elsewhere. There was mention of a engine coolant sensor failing internally and allowing coolant up the wire and into the ECU

mitchino wrote:So after topping up the brake fluid and drying out the ecu connector and port, the car seems to be working normally, no beeps so far, idling at 1000 rpm and not revving like crazy at the slightest touch on the accelerator.

Good news, thanks for the update

Ordered an obd reader, coming thursday.

Good point about brake fluid leaks, there must be one somewhere. I had similar brake problems 2 years back, it was a loose bleed nut behind the radiator. Checked that today, seems ok.

Am I right in thinking the power steering uses the same fluid/reservoir? Another occasional problem is that the power streering takes a few seconds to kick in, I have to be careful when starting the car and driving off.

So my OBD reader came, a KONNWEI KW808. What a great unit for next to nothing.

Anyway, no codes present, surprised by that, but there you go.

One thing I like about the C3 is it's never actually completely broken down on me in almost 90,000 miles, well apart from once but the RAC fixed that in a couple of minutes.

mitchino wrote:Am I right in thinking the power steering uses the same fluid/reservoir?

No, you have electronic power steering (EPS) driven by an electric motor and no fluid used.

mitchino wrote:I had similar brake problems 2 years back, it was a loose bleed nut behind the radiator. Checked that today, seems ok.

The clutch bleed nipple

mitchino wrote:Another occasional problem is that the power streering takes a few seconds to kick in, I have to be careful when starting the car and driving off.

You will need more than a standard OBD reader to diagnose that, the full lexia system will do the EPS, but you should start by checking the alternator/batter voltage while the EPS is off line and again as it comes back online.

mitchino wrote:So my OBD reader came, a KONNWEI KW808. What a great unit for next to nothing.