Starting Problems

[Carmen]

Hey Guys,
Wondering if anyone could give me advice on this.
My 2005 Clio began struggling to start first time, it was cranking but not firing up. Then my Toxic Fume Warning Light came on. After some googling, i thought it was most than likely my Lambda sensor. The car went in for a service, this put the light off and since then it has been fine.

Last week it began struggling to start again, however no light has came on yet. Each time it has started eventually but for the first couple of minutes the car seems to be 'bumpy' as if its struggling for oxygen, then it calms down and it's fine. Today though i couldn't get it started at all.

When i spoke to a garage, they told me it was most likely an electrical fault. Because i really don't have a clue, im just wondering if anyone has any advice? Before i put it in to get fixed.

Thanks in advance.

 

[172PSD205]

Hi, I'm in Dumfries and I'm a ex Renault tech I could help you out if you want?

 

[Carmen]

Hey! Aww that would be great thank you! I think I know what it is but I'm not sure

 

[172PSD205]

Hey! Aww that would be great thank you! I think I know what it is but I'm not sure

Give me a shout if you need me to plug my diagnostic computer onto your car.

 

[Rone]

Yeah probably lambda (exhaust gas reminiscent O2-sensor) or MAF (Mass Air Flow) / MAP (Intake Manifold Absolute Pressure) sensor.

The MAF/MAP can be ruled out by unplugging the MAP/MAF connector(s) and trying to start the car with the sensor disconnected; if it fires up you've found the
culprit.

The coolant temperature sensor (CTS) is also one possibility. Perhaps the ambient temperature has been changing lately to a more coldish and the CTS might be sending a constant "hot engine" temperature reading to the engine control unit. Thus, when the outside temperature decreases, the cold-start air-fuel-mixture diverts ever more away from the proper cold-start mixture the ECU should be providing. Thus, making the car the harder to start the colder it is outside. This would also explain why the running settles after a couple of minutes as the engine heats up slightly.