306 cuts out

cmm-racing · Unread post by **cmm-racing** » 30 Nov 2010, 13:13

I've recently bought a 1998 reg 1.4 306 and since buying it I've found out that they are prone to running and idleing problems. My problem is slightly different, it idles and drives 100% however every now and then it will cut out completely. If i'm stopped at traffic lights for example most of the time it will sit the idleing fine but sometimes it will just cut out as if someone has turned the ignition off. It starts up again first turn of he key. It also does this during driving on the motorway etc. So far i've tried

- coil
- lambda sensor
- throttle potentiometer
- crank sensor

With no luck so far. Anybody got any ideas of what it might be?

Oldpug · Unread post by **Oldpug** » 30 Nov 2010, 15:36

What about the stepper motor?before you replace it try cleaning it and the housing as they get gummed up.After replacing all these sensors it is best to have the fault codes cleared and the ECU re-set.Did it have a diag` check in the first place as this seams very hit and miss.

cmm-racing · Unread post by **cmm-racing** » 30 Nov 2010, 19:38

I've not put it on a diagnostic machine because I doubt it would come up with a fault as it doesn't run rough it just cuts out therefore the diagnostic machine would probably think the ignition has simply been turned off. I've disconnected the battery today in the hope that it will re-set the ecu settings. The scrap yard i'm getting the parts from just let me swap the parts so it's only cost me a tenner to try the different parts. I'll give the stepper motor a go.

Unread post by **CitroJim** » 30 Nov 2010, 20:25

A good and likely candidate is the double injection relay, the one that feeds the injectors and fuel pump.

Have a look at the instruments next time it cuts out. Do all the gauges fall to zero and the warning lights come on?

cmm-racing · Unread post by **cmm-racing** » 30 Nov 2010, 23:03

Ah that sounds like it could be a good shout, it does kind of seem like the fuel has suddenly been cut off. Yeah all the warning lights come on just like when you first turn on the ignition. How would I identify the fuel relay.

citronut · Unread post by **citronut** » 01 Dec 2010, 13:32

its usualy brown and twice the length/size of a standerd relay, and is usualynear or atatched to or inside the engine ECU houseing under the bonnet,

regards malcolm

cmm-racing · Unread post by **cmm-racing** » 06 Dec 2010, 09:22

Changed the relay for a 2nd hand one then took it for a drive and for about 10 miles it was fine but then on my way home it cut out again twice. so i'm back to square 1 now.