Intermittent starting problems - 172 Turbo

[Fishfire]

The last couple of weeks my Clio 172 turbo has had an intermittent starting issue which I think is actually two different issues.

First issue: occasionally when you try and turn it over, all I get is clicking.
I've found that depressing the clutch pedal will, 9 times out of 10, release this and it will turn over. It's like the clutch is sticking. Still not sure why this should be the case?

Second issue: once it does turn over, occasionally it just won't start.
It will turn over 4 or 5 times and cut out of its own accord despite having the key still turned. i.e it doesn't continuously crank but cuts off after a few cranks.
It seems like the fuel pump isn't priming.
The pump is a brand new Bosch item for a phase 1 with the fuel return that's needed for the turbo set up.

It played up this morning so we tested to see if the pump is getting power, but could only read 10v getting to the pump connector.

Things I've done:

- brand new Bosch fuel pump ( part no. 0986580204)

- brand new Lucas starter motor fitted in the last week.

- all three small black relays changed for new items ( starter, injectors and fuel pump relays I believe?)

- Brand new crank position sensor fitted in the last week.

It's not the immobiliser that I can see. I have two working keys, which both have the same result when it starts playing up. The imobaliser light also isnt flashing, indicating the car is imobalised

This has got me scratching my head......anyone experienced these types of starting issues? All the usual suspects have been changed for brand new items.

I'm half tempted to change the Bosch pump for a Walbro item, which was a mod on my list to do anyway but other than that......🤷

Ideas?!

 

[RustyMojo]

Have you checked the earths and the white plug of doom?

 

[Fishfire]

Earth's seem good.

White plug of doom?! Sounds like a thing I need to check! What am I looking for?

 

[RustyMojo]

Under the engine bay fuse box, the loom plugs into a big white connector. Moisture gets in and the pins corrode slightly. Causes most of the electrical gremlins I have seen in recent years. You need to strip it all down and clean it properly. Using some fine wet and dry on each pin. Then contact cleaner then file with dialectic grease. It’s not a quick job, but before you fire the parts cannon much more do that. I’d also double check the earth strap to the gearbox under the passenger side arch liner. Clean up the contacts and personally I’d replace anyway given how cheap they are

 

[Fishfire]

Under the engine bay fuse box, the loom plugs into a big white connector. Moisture gets in and the pins corrode slightly. Causes most of the electrical gremlins I have seen in recent years. You need to strip it all down and clean it properly. Using some fine wet and dry on each pin. Then contact cleaner then file with dialectic grease. It’s not a quick job, but before you fire the parts cannon much more do that. I’d also double check the earth strap to the gearbox under the passenger side arch liner. Clean up the contacts and personally I’d replace anyway given how cheap they are

Brills! I'll give that a go 😃

Much appreciated 😁

 

[Fishfire]

Resolved (so far🤞)

Combo of all new relays and cleaning up the connector block under the fuse/relays in the engine bay seems to have done the trick.

Thanks all for the pointers 😁😁

 

[PsymonS]

@Fishfire do you happen to have a link to the relays you bought to replace the 3 smaller ones? My Google skills don't seem to be good enough to find some replacements, and Renault told me you can only buy a complete fuse box, which is discontinued!

 

[Fishfire]

@Fishfire do you happen to have a link to the relays you bought to replace the 3 smaller ones? My Google skills don't seem to be good enough to find some replacements, and Renault told me you can only buy a complete fuse box, which is discontinued!

Sorry for the late reply.

They're standard Bosch relays. I'll dig them out the car tomorrow and put the part numbers up