Cannot start when warm

[rctempire]

Mark 1 Clio 16v

Been annoying me all day.
Swapped the radiator sensor but nothing at all yet.
Car has a fuel pressure regulator and apparently a uprated ecu.
But car is fine when cold. When hot it will not start at all.
Sparks fine, all leads ok, Coil pack fine. All electric s are good and working
Ideas?

 

[MicKPM]

Sparks 100% there when warm/hot and still no firing?

 

[rctempire]

Sparks 100% there when warm/hot and still no firing?

Correct. When cold great. When warm turns over, no play.

Sparks there both hot and cold.

 

[MicKPM]

Okay so we've ruled out the common crank sensor fault then because we have spark meaning the ECU is seeing and recognising rotation/trigger pattern.

That means it's either fuelling or a mechanical fault such as compression.

Does it cough,stutter or show any other signs of attempting to start?

 

[rctempire]

When cold it stars hesitantly but when going fine.
First few mins it's not happy low revs, then fine.

It can totally cut out when accelerator is pressed.
Incase that helps matters.

 

[Jaff.]

dicky icv?

 

[MicKPM]

Compression test it

 

[.GAZ.]

Burn it

EFA.

 

[MicKPM]

That would 100% offer a solution to the problem but lets assume he is gluten for punishment and wants to drive the car hehehe

 

[rctempire]

SOlution was - BURN IT.

Serious, obvious was the coolant temp sensor on the thermostat. Replacing that tomorrow, results could be good.

 

[MicKPM]

I thought you'd already done that.

 

[rctempire]

I thought you'd already done that.

Did the radiator temp sensor, not the thermostat one.

 

[MicKPM]

I misread that then... CTS will sort it

 

[rctempire]

Hi chaps,
Ok so no change.

Heres some added info.

Wont start when hot, but after a few turns on key to try start.
Battery sounds flatter, but then it it starts, occasionally.

Ehhhh.

 

[ADS_V6]

had same on my 172 i replaced the car battery as cts sensor didnt fix it ,someone on here suggested it and another sign was my trip computer kep resetiing try a new battery can always get a refund in halfrauds if battery is ok m8

 

[MicKPM]

You changed the correct CTS yeah as these have two?

 

[rctempire]

Where's the second?

 

[MicKPM]

On the thermostat housing. It's been a long time since I've seen a Mk1 but there is one for the gauge and another for the ECU. I believe one is Brown and the other is White but cannot remember which is which.

 

[rctempire]

 

[rctempire]

That one I took the middle one out

 

[MicKPM]

Unplug them all and see if it starts

 

[rctempire]

Think its compression testing tonight.

 

[MicKPM]

About time lol

 

[rctempire]

Ok compression test

180, 155, 160, 170
From driver side.

That was when warm.

So thoughts

 

[MicKPM]

Assuming that's a dry test, did you follow up with a wet test?

 

[rctempire]

Plugs out, engine spun.
So presumably. I'll need a dry test. Next

 

[Dan@SJM]

No, that was a dry test. Wet means a cap of oil down the bores and repeat the test

 

[rctempire]

No, that was a dry test. Wet means a cap of oil down the bores and repeat the test

Ok wasn't aware of this.

What should the result be close too then.

 

[MicKPM]

It's not what the results should be but the effect the wet test has on the dry test values.

I suspect a head gasket issue

 

[rctempire]

It's not what the results should be but the effect the wet test has on the dry test values.

I suspect a head gasket issue

I m hoping it's something that crops up. Least I can get it sorted, right now it's like pissing into a chip packet hoping it doesn't burst.

I'll try again tonight and update you all. Thanks

 

[rctempire]

Some videos for you.

 

[rctempire]

Chaps.

Opened the ECU up. Its got a superchip inside it.

 

[barnesautos]

The CTS your looking for is the white coloured one on the thermostat housing . Yes @MicKPM your right the brown one is for the gauge and the twin one is for the ECU.

 

[rctempire]

Anyway, this car has a superchips map. So I think its the Fuel Pressure when its warmer, ie may be totally crap. Ordered a gauge to resolve that.
The coolant temp sensor has been renewed and swapped, so its nor that. Crankshaft sensor has been changed too. So have spark plugs.

 

[MicKPM]

Just remove the FPS

 

[rctempire]

Just remove the FPS

Hi Mick, When I do, the car wont run at all. Soon as I connect it, fires up no issues.

Wonder if its pressure is incorrect. I have ordered a new FPR with a gauge to resolve.

 

[rctempire]

Try the Cold Start Injector (In person)

Nope, wasn't plugged in at all. Was connected but not plugged in to the loom

Just remove the FPS

Found out after replacing the Fuel Regulator, starts all the time, every time, now.

Just need to get the right pressure and jobs a good one.

 

[rctempire]

No, that was a dry test. Wet means a cap of oil down the bores and repeat the test

Just remove the FPS

OK chaps, even the company who do the superchips wont touch it.
Another tuning company said it couldn't be the ECU based on what I told him.

So, what next? Any ideas?

So, starts when cold all the time. Soon as I turn it over and move it say 5m or more, it refuses to start. I have to wait say 30 mins for it to cool down/what ever then it will start first time.

 

[Dan@SJM]

Unplug all the sensors except for:
Crank sensor
Map sensor
Throttle position

See if it starts
If so then slowly plug sensors in until it won't.

 

[rctempire]

Unplug all the sensors except for:
Crank sensor
Map sensor
Throttle position

See if it starts
If so then slowly plug sensors in until it won't.

Oh my, this will be a long process, heating and cooling the engine.