Won't start

[Tomo_Rep.97]

clio won't start this morning. Runs fine but not firing up. It turns over fine but never fires up. Even doing full throttle there is no obvious smell of petrol from the exhaust, suggesting it's getting no fuel, where can the fuel pump be found? Any suggestions?

 

[fairm010]

I believe the fuel pump is located under the rear bench on the drivers side of the car. Just pull the bench up to see the rubber grommet. You should hear it prime when you start the car.

 

[Tomo_Rep.97]

Cheers mate! Seems quite a common fault with Clios not starting. But just so many different things it could be. I'll have a look, cheers.

 

[Budgie]

LOL at no fuel smell in the exhaust.

No, no, no.

Just no.

Check spark. Check there's fuel at the rail. Check crank sensor.

Will it start with easy start/petrol being sprayed in the TB?

 

[Tomo_Rep.97]

LOL at no fuel smell in the exhaust.

No, no, no.

Just no.

Check spark. Check there's fuel at the rail. Check crank sensor.

Will it start with easy start/petrol being sprayed in the TB?

If everything was running fine and fuel was being pumped then surely as the engines not running you would have a pure petrol smell? As the petrol wouldn't be burning. Checked all that, haven't got the right thing for the spark plugs! Cleaned crank sensor. About to try again.

 

[Budgie]

If that was the case, when it did finally fire it would set fire to your exhaust.

To rule out fuel being the case, as the engine is cranking, use a spray bottle and mist some fuel in the TB. If it coughs/fires/tries to run then it's not getting fuel right.

Spark - whip out one of the plugs and crank. Plug needs to be touching the engine to earth. Check for a visable strong spark. While it's out, check for wetness/any visable signs of abnormality.

 

[Tomo_Rep.97]

Won't start again. Crank sensor cleaned. Should I try jump starting? Any suggestions. Haven't got the correct spark plug socket.

 

[Budgie]

If it's cranking strongly enough then it's unlikely to be affected by jump starting.

Try the fuel spray trick first IMO.

Could try a bump/push start.

 

[Tomo_Rep.97]

Don't want to be thick but what's the TB and where do I find this? Spark plugs are nearly new so wouldn't think it would be them.

 

[Tomo_Rep.97]

It's cranking fine, battery seems good. I think I'll give that a go

 

[Budgie]

Throttle body.

Basically, take the air filter and inlet elbow off. Then spray fuel in there with a mister as it's cranking.

 

[Tomo_Rep.97]

okay decent cheers mate. Will give that a go while the battery still has some life in it.

 

[Tomo_Rep.97]

Struggling with the petrol in spray bottle now, not going through the tube to spray

 

[fairm010]

Have you turned the nozzle to the On position?

 

[Tomo_Rep.97]

Nope, that didn't work mate.

 

[Tomo_Rep.97]

Yes nozzle was on I'm not a idiot it was just the bottle didn't work, used a different bottle it worked. Try starting while someone sprayed petrol in TB but that didn't work. What next?

 

[bloke]

if it's cranking and your imobiliser is clearing then chances are it's crank sensor.
can you hear the fuel pump prime?

 

[Typhoon]

Yes nozzle was on I'm not a idiot it was just the bottle didn't work, used a different bottle it worked. Try starting while someone sprayed petrol in TB but that didn't work. What next?

Head gasket was probably knackered on the old bottle. Was it an old Mr Muscle bottle? They're prone to the gasket going.

Did you check all the plugs or?

 

[fairm010]

I know your not mate, was pulling your leg. I had that once, replaced my crank positions sensor and it was all good. OBD is a godsend.

 

[Tomo_Rep.97]

if it's cranking and your imobiliser is clearing then chances are it's crank sensor.
can you hear the fuel pump prime?

The fuel pump primes like normal. Crank sensor has been cleaned, the magnet is fine too.

Head gasket was probably knackered on the old bottle. Was it an old Mr Muscle bottle? They're prone to the gasket going.

Did you check all the plugs or?

Was an old kitchen cleaner bottle, it worked with water but not petrol, strange. found one that worked though.

Haven't checked the plugs yet. Plan too tonight when my brother brings his socket round. What do I look for when plugs removed?
Cheers

I know your not mate, was pulling your leg. I had that once, replaced my crank positions sensor and it was all good. OBD is a godsend.

Haha sorry, didn't mean to bite frustration got the better of me! Problem is can't throw money around on parts and find out it's not them, crank sensor seems to be good! Brothers coming round later to bring his socket for plugs, he has a 2006 Clio, could I try using his sensor off his car to see if it is the sensor or would that mess things up as its newer?!

Battery is charging at the minute as it was starting to drain. Fuel pump primes when ignition is turned on. Crank sensor seems good. Did a voltage test on the fuel pump and it was only 4.3 volts when ignition turned on, with the positive on bare wire and negative on bare metal. I assumed this had to be 12v? Or is this only 12v when the engine is running?
Plan to check the plugs later on tonight. Thanks for help so far.

 

[Typhoon]

Inspect the spark plug for very stubborn deposits, or for cracked porcelain or electrodes that have been burned away.
Swap them round as well, and check if they're actually sparking.

 

[Tomo_Rep.97]

Nice one, will give it a go later. Cleaning the plugs, just a rag? As I don't have any kind of cleaner at the minute, any other alternatives?

 

[Budgie]

Clean them with petrol. But cleaning stuff won't make it start.

If they're sparking, my bet is crank sensor.

 

[Tomo_Rep.97]

Clean them with petrol. But cleaning stuff won't make it start.

If they're sparking, my bet is crank sensor.

Could I try my brother sensor on my car?
I'm guessing the sensor is only available online and no where I could go buy one?

 

[Budgie]

How about Renault?

Or ECP? Or GSF?

 

[Tomo_Rep.97]

Okay after charging the car up for a bit, try the starting while spraying fuel into throttle body it's now started. Proving its not crank sensor. I was right it's not getting fuel. It's not running too good either, with foot nice and still he revs are bobbing up and down. While it's running should I just get it to a garage as it seems to be a problem where the engine is not getting fuel.

 

[Tomo_Rep.97]

Thanks @Budgie for that idea, now a case of now what haha

 

[Tomo_Rep.97]

It's been running for a good 10 minutes now and it's running nicely. Just the start up needed fuel.

 

[nd-photo.nl]

In my Seat Leon the crank sensor prohibits fuel (as safety measure). I think the Renault works the same way, no good signal from crank sensor = fuel cut. Mine had issues with starting as well (cold starts0, cleaned the crank sensor and it starts first go again. I have ordered a new crank sensor just to be safe.

 

[Tomo_Rep.97]

Well I didn't know that. I'll have a look into that. How can you diagnose a bad sensor though? I don't want to just spend £20 odd quid and for it to be the exact same! I'll look into it though thanks

 

[nd-photo.nl]

Well I found this when replacing it on my Leon

New vs Old by Andy Ramdin, on Flickr

It will probably have worked again after a good cleaning session, but I didnt want to risk it. I found out because of another forum member, else I would have gotten the fuel pump replaced (already ordered it etc). Please note the info below is for a VAG car, but will probably work the same for our frenchies.

Fuel pump issues due to the crank position sensor
The ECU shuts off the fuel pump if it doesn't get pulses from the crank position sensor; the purpose of this would be to reduce fire hazard in the event of a crash, by shutting off the fuel supply.

Crank Position Sensor
This sensor tells the engine how fast the motor is turning. In other words, you can directly correlate the pulses from this sensor into RPM's. The crank position sensor wheel has ___???____ windows per revolution.

Diagnosing the Crank Sensor:
When the crank sensor fails and causes an out-of-sync situation with the ECU the ECU cuts response to the throttle in order to prevent major engine damage. This throttle cut generally happens within a certain RPM range.

Another symptom you may also notice is that your tach (RPM) gauge hangs at a higher rev even though the car's speed is slowing. This symptom is due to the throttle being restricted by the ECU, as previously described.

Yet another symptom is the car wont start on cranking. This is because the ECU cannot determine how fast the crank is rotating due to the failed or failing crank sensor. This problem is further exacerbated by the electrical interference the starter is throwing out as you are cranking the engine which further confuses the ECU. This starting symptom is commonly incorrectly diagnosed as a failing starter throwing out extra electrical interference. However, this is rarely the case and is simply a failing or failed crank position sensor.

If the sensor is fine the problem can be mechanical. The crank position wheel is attached to the crankshaft via press fit and then secured with a screw. The screw can come loose, the screw can fall out, or the screw can shear off. Also, during old maintenance on the car the wheel can be bent by a careless mechanic which can throw off the crank balance a bit, increase the likelihood of the screw problem previously mentioned, or simply confuse the crank position sensor. This mechanical problem is typically not seen on cars turning stock RPM's (under 7500) and stock displacements. It is far more common on stroker setups or setups that turn high RPM's (over 7500). Both of these setups cause increased vibrations on the crank and in turn, put more stress on this crank position wheel. The fix for this problem if you are building a high RPM or stroker setup is to tack weld the screw in place or fully weld the entire position wheel in place.
You can get a replacement crank sensor for $20 online. It's a cheap fix for a big problem.

Source: http://forums.thecarlounge.com/showthread.php?5417830-FAQ-Links-DIY-Reference-Table-of-Contents-1-8t

 

[Tomo_Rep.97]

Okay after cleaning the spark plugs, changing the sensor, my car was running smoothly and started every day since this post, come to my car today and it won't start! Help? Not crank sensor, not spark plugs. It's turning over fine. Battery is good!

 

[nd-photo.nl]

Something with fuel delivery? Can you hear your fuel pump when turning it over?

 

[Tomo_Rep.97]

Doesn't the fuel pump prime when ignition is turned on? It isn't possible to hear the quiet pump when it's turning over. I just tried spraying fuel into the throttle body while engine was turning over but that didn't work either, I hear the pump priming when ignition is turned yes, been starting fine since sensor changed too!

 

[fairm010]

Find out if there is anyone nearby with an OBD reader. That should point you in the right direction perhaps.

 

[Tomo_Rep.97]

Find out if there is anyone nearby with an OBD reader. That should point you in the right direction perhaps.

Good thought, cars doing my head in at the minute, in a low! Kinda in 2 minds as to whether to get something more reliable and sell the Clio! Is it really worth all this hassle I ask myself

 

[fairm010]

Sometimes I think that. Then I realise how much time and money I have poured into the car. Too much to get so little back yet!

 

[Tomo_Rep.97]

We are definitely in the same boat then haha! But won't you get more for it now compared to a few years time?

 

[fairm010]

I am enjoying the car at the moment, minus the crap wrong with it at the moment. Its a very low mileage car so we shall see what happens.

 

[Tomo_Rep.97]

Just rolling started it and took it too a local garage, it's booked in for Monday now. Started fine after stopping at the garage too! I'll post in here the outcome!