Citroen C5 1.8I Electrical Gremlins?

[Homley]

A couple of months ago I bought my first Citroen, a 2007  1.8i C5 Design with 104,000 miles and an LPG conversion that seems ideal for the several long trips I’ll be making this year from Edinburgh where I live down to Norfolk, the comfort of the C5 and the economy of the LPG conversion making this an ideal vehicle for me.

 

Everything so far seems ideal, (I averaged 38 MPG on petrol last week during a hard fast return drive from Edinburgh to Loch Ness so not complaining about that), apart from what seems to be some electrical gremlins which sees the anti-pollution light & the ABS sensor light come on occasions, (separately), with it sometimes starting to run rough at tickover, (although switching it off and restarting it always clears and runs smoothly again, although the Lambada sensor light will sometimes stay on, going out again randomly), and the ABS sensor light normally coming on when you have stopped in traffic and the car is being held on the footbrake, (it normally going off after a restart).

 

Apart from that, and the car dipping it’s front end when you stop, but with the engine still running, (seems the front suspension lowers, is this normal?), the car’s fine and I love it but am concerned that the electrical gremlins that the car is currently exhibiting will get worse and the car end up letting me down, (which it hasn’t so far in the 4,000 miles I’ve done in the 2 months I’ve had it).

 

Can anybody suggest what this could be and how I can resolve it, is there any way I can “flash†the ECU or will it need replacing, (I’ve been told that that’s expensive, would cost almost what the car is worth), as I like that car and want to keep it, but am terrified of a massive cost that I can’t afford in the near future.

 

Any advice/suggestions gratefully received.

 

Highest regards,

 

Homley

[paul.h]

Welcome to the forum.

 

You may have a few separate problems to sort out and the lpg conversion might have something to do with the anti pollution message to complicate things.

 

What is the lambada sensor light ? If you mean the engine management fault light (engine symbol) there will be a fault code stored which can be read using a code reader to give you an idea of what is wrong. In fact it may be worthwhile to have a diagnostic check for the engine problems and the abs problem - this could cost less than replacing lots of parts hoping to guess the fault. Ideally a Lexia should be used and there are some members able to help others with this - see separate topic on the C5 Technical section, Diagnostic Help. I would not touch the ecu since the faults mentioned do not suggest anything wrong with it and it might have been programmed for the lpg conversion.

 

The front end lowering when you stop is not normal unless possibly you have just got out of the car. It could be a height sensor is a bit seized and taking the suspension up and down a few times can help. The height sensors are fastened to the front and rear anti roll bars, approx in the middle, and a spray with wd40 can help - if you go under the car use axle stands since if the height sensors are touched the car can drop to a very low level (or use a ramp).

[coastline taxis]

All normal for a lpg conversion. when you switch to gas it shuts the fuel of and the car thinks it has no petrol which will affect the fuel rail pressure and the emmision are that clean on gas it puts the cat sensors out of range and puts the lights on

[Homley]

Welcome to the forum.

 

You may have a few separate problems to sort out and the lpg conversion might have something to do with the anti pollution message to complicate things.

 

What is the lambada sensor light ? If you mean the engine management fault light (engine symbol) there will be a fault code stored which can be read using a code reader to give you an idea of what is wrong. In fact it may be worthwhile to have a diagnostic check for the engine problems and the abs problem - this could cost less than replacing lots of parts hoping to guess the fault. Ideally a Lexia should be used and there are some members able to help others with this - see separate topic on the C5 Technical section, Diagnostic Help. I would not touch the ecu since the faults mentioned do not suggest anything wrong with it and it might have been programmed for the lpg conversion.

 

The front end lowering when you stop is not normal unless possibly you have just got out of the car. It could be a height sensor is a bit seized and taking the suspension up and down a few times can help. The height sensors are fastened to the front and rear anti roll bars, approx in the middle, and a spray with wd40 can help - if you go under the car use axle stands since if the height sensors are touched the car can drop to a very low level (or use a ramp).

 

Thanks, I'll check all that out and I see that there is a member close to me with the right diagnostic gear, I'll PM him and see if he can help me out with a diagnostics check.

 

I said Lambada sensor light as that's what I thought was causing the problem, (it said "Anti Pollution System Fault" on the screen), and Coastline Taxi's has confirmed my suspicions on that, but when the ABS light comes on the engine runs rough till I restart it, (when the light goes out), although I suspect that may be some sort of limp mode triggered.

 

All normal for a lpg conversion. when you switch to gas it shuts the fuel of and the car thinks it has no petrol which will affect the fuel rail pressure and the emmision are that clean on gas it puts the cat sensors out of range and puts the lights on

 

Thanks, you have confirmed something that I had suspicions of :)

 

Homley

[coastline taxis]

Just been checking a few things and to put it rite we would start with a remap but explain that you need the  upper and lower range altered for the sensors. And to be honest i think that would be above most people,s understanding as a lot of other settings would need adjusting so it all worked in harmony with each other. try running on petrol only for a few days and see if the faults go away