Citroen BX not starting

HH1

New member
My 1991 BX Q6V GTI has just stopped starting all of a sudden. Have checked and there is no spark. There is no b spark to the distributor. Don't know what's wrong but suspect its the electric ignition. Does anyone have any ideas? Thanks in advance. Sohan.
 

frog

Member
Hi, I had the ignition coil go on mine not too long ago. Might be worth swapping that out for a known working one if you have one available.
 

Ken W

1000+ Posts
The ECU on these does not turn the ignition or injectors on until it gets a good signal from the crankshaft sensor.

Is your fuel pump running when you are trying to start the car? Old fuel can cause the fuel pump to stop rotating - even on new replacement pumps.

It could also be the ignition module between the ECU and the coil that has failed.

If it is firing sometimes and not starting, try a new set of spark plugs.

Cheers, Ken
 

HH1

New member
Thank you. Looks like there is no spark going to the distributor. So I think it's the ignition or coil, but u have to check further.
 

HH1

New member
Hi guys, looks like the ecu is the issue. Anyone know where to get one? Its for a 1991 Bx 1.9 GTI 16V. Thanks.
 
My 1991 BX Q6V GTI has just stopped starting all of a sudden. Have checked and there is no spark. There is no b spark to the distributor. Don't know what's wrong but suspect its the electric ignition. Does anyone have any ideas? Thanks in advance. Sohan.
There are 2 relays in the engine bay, drivers side on the inside of the mud guard - usually covered by plastic bags. There are for the fuel pump and the ignition. If either one is not working it will not start. Give them a "technical tap" then listen/feel if they activate with the ignition switch. Pull out and put back - might be a dicky connection. You can swap them over - they are the same - and see it it works.
 

Ken W

1000+ Posts
Sohan,
How do you know it is the ECU?

Can you tell me the Bosch number on your ECU please - I have 2 BX 16Valves in the back garden in Brisbane - not far away.

Cheers, Ken
 

HH1

New member
Sohan,
How do you know it is the ECU?

Can you tell me the Bosch number on your ECU please - I have 2 BX 16Valves in the back garden in Brisbane - not far away.

Cheers, Ken
Hi Ken, Please see the attached picture.
 

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HH1

New member
There are 2 relays in the engine bay, drivers side on the inside of the mud guard - usually covered by plastic bags. There are for the fuel pump and the ignition. If either one is not working it will not start. Give them a "technical tap" then listen/feel if they activate with the ignition switch. Pull out and put back - might be a dicky connection. You can swap them over - they are the same - and see it it works.
Hi Michael, the mechanic thinks it's the ecu because it's corroded. But I'll tell him your suggestion too.
 
Hi Michael, the mechanic thinks it's the ecu because it's corroded. But I'll tell him your suggestion too.
The relay was my problem when I had no spark. This is a quick - read less cost - first check. The relays are in the plastic covers up against the inside of the mudguard, beside the sphere.
 

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HH1

New member
The relay was my problem when I had no spark. This is a quick - read less cost - first check. The relays are in the plastic covers up against the inside of the mudguard, beside the sphere.
Hi Michael, thanks, we've checked that, and all seems fine. The ecu is corroded and now an trying to find a replacement.
 

HH1

New member
I've replaced the ignition module and the ecu too. Starts up. I'm wondering what the firing order is and if anyone has a diagram for the distributor. Thanks in advance.
 
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