Ph2 172 not starting - bad earth?

[Wizbit]

So I try and leave my fiancee's parents house and right out of the blue my car refuses to start... *^@&^£%!!!!

All lights on dash are bright and the immobiliser light goes off when trying to start. Turns over no problem at all and no warning lights are on.

Checked all fuses so the only thing I reckon it be is a bad earth as I have noticed the rear fog dash light flickering when braking and signaling over the past few months - plus it has been getting brighter recently.

Now can a bad earth stop the car from firing and/or starting? If so, then whereabouts could it be? If it's affecting the rear lights clusters, am I best to start looking around there? Also, if I can get it started, is it likely to cut out should the fault (bad connection) reoccur?

Thanks in advance for any advice. Looks like I am staying here for the night...

...and yes I have got fuel in it!

 

[bmh.01]

The fog light is nothing related really, thats just moisture in the back lights making it track across. Clean them up and that'll go away, if you disconnect the clusters in turn that'll enable you to see which side it is.

Starting wise, getting fuel/spark?

 

[Cro]

if its turning but just not firing id assume tdc sensor

 

[bmh.01]

if its turning but just not firing id assume tdc sensor

Thats what I was going along the lines of, if it isn't getting and fuel/spark then theres a good change its the CPS.

 

[Wizbit]

Cheers for replies guys... RAC man reckons it's a faulty camshaft sensor.

Seems like an easy enough job. Anyone know if it is and how much it is likely to be from Renault?

 

[bmh.01]

The crank position sensor is about £40 or so iirc. Take the airbox out and and its easy enough to get to to change.

 

[bmh.01]

Just checked for you, they're about £25 but theres a section of wire that has to be changed if its an older sensor.

 

[Wizbit]

Thanks again for the exrta info - although the RAC man was certain it was the cam sensor and not the crank sensor.

Went into Renault to get the part and it turns out the 172 doesn't not have a camshaft sensor. Since it has VVT, it has a different sensor instead and the bloke I spoke to at Renault said that it is very very rare for them to go.

So... I am just going to have to get it to a Renault garage for a proper diagnosis instead of just trying to second guess the fault... having said that, if it is the crank sensor, then I will be annoyed at spending more money than I have to on a job that I could have done myself!

 

[bmh.01]

As you've already found theres no cam sensor as the ECU works out cam position from the crank position, for the reletive little cost change the crank position sensor first and i'll bet thats what it is.

 

[Wizbit]

Yeah - I think you are right actually. The dude at Renault (who was surprising helpful!) said a similar thing. Worth a gamble for £25 I reckon.