Help clio 1.5 dci not sarting!

[ali1202]

as title say my friend bought a clio 1.5dci as a non runner needed and engine so he bought i built and fitted,but i can not seem to get to start no fault code showing,to me seems like a fuel issue i have had another tech look at it with me to check every thing after me to make shure all is ok thought off the usual pressure sensor and such like but all checking out ok when checking live data on bosch diag machine fuel rail pressure was 645Mpa i have been told this i far to low i need 400bar from the pump.i striped the deisel pump to make shure no damage but looks all ok.checked injectors with a node light and none are reciveing a sinal to open checked all wireing all ok iam now scraching my head:banghead: any help please!!

 

[Dan@SJM]

You really need to scope the injectors to see if they're firing, a noid light (from experience) can't react quick enough.

 

[scarble]

400bar? I was under the impression current production rail pressures are uh.. 200..oh.. no, 2000 bar. But I don't know what a 1.5 dci of whatever year would have so 400 bar might be right?

But 645MPa is.. uhm.. 6450bar so you either have a super secret future ultra high pressure diesel system far in advance of the current state of the art next-gen systems or you're reading it wrong or something is wrong somewhere.
Or I'm being thick.

If it's not even trying to inject maybe it doesn't realise it should be injecting? Maybe as simple as cam or crank sensor?

Oh and what Dan said, injector pulses are in the micro second range so you won't see them with a light bulb.

 

[ali1202]

Its a 51 plate clio.new crank sensor and new cam sensor so unless the new renault parts are faulty.the fuel rail sensor is getting 0.5v on crank.mybe wrong with the Mpa reading then i will double check.i will scope the injector to make shure aswell.dose the ecu need to see it a certain amount off pressure in the pump and rail befour allowing the injectors to open?

 

[scarble]

idk, ask bosch. maybe. probably.
if fuel pressure is low there are a few things like the rail pressure relief valve and probably some regulating valves in the pump.
these valves are usually springy type things and after a few activations the springs can get softer so they open at lower pressure, to the point that sometimes you can't maintain rail pressure.
does it have an electric lift pump? that could be knackered.

on the plus side you've got a whole other fuel system to scavenge bits from right?
what was wrong with the old engine?

 

[ali1202]

sorry was looking at the wrong pressure its getting 0.1Mpa on crank.i will scope the injectors and see what iam getting.

 

[ali1202]

no its a vaccum on the deisel pump i have check this and it was drawing about -60kpa i assume this would be fine for a fuel lift.i dont think the high pressure side is working not shure if it is air locked.i have had the solinoid off and powerd it and it seemed to work ok it is on the back off the pump.

 

[ali1202]

original fuel system he only bought the head,block,pistions camshaft and new internals the old engine had been timed worng by a "gumtree mechanic" and cracked all pistions bent valves and cracked the cam.i have never seen this car run so it maybe even worse than it looks.

 

[scarble]

-60kpa sounds low, are you sure it shouldn't have a lift pump?? I'm used to working with bigger diesel engines I guess.
0.1MPa also sounds low, that's only 1 bar (1 bar = 100,000 Pascals) which sounds very low for a high pressure system. It is common rail isn't it?
As I said pressure relief valves can leak.

Scopey scope time really.
I'm fairly certain that at summer-time temperatures if diesel is going in the cylinders and the engine is turning you will get a bang, so fuel ain't getting in. Or air isn't..?
Electrically sound, lights work ok and they don't dim as you're starting? Modern injectors require a fair old current to drive them I guess..

Are the symptoms on this non-running engine different to the original non-running engine?
Which ECU are you using? Have you matched the ECU, UCH and immobiliser?

 

[Dr HMS Derv Destroyer]

Put some easy start down th intake and crank the engine, it should build enough pressure to idle and leave it idle'n sound lik air in the system

 

[scarble]

:lolup:

 

[ali1202]

yeah i thought that 1bar was a little to low aswell not shure about the vaccum thow only two wires at the sender in the tank so it hasnt got a electric pump.not shure the sypmtioms befour as it was a blind buy realy.haha yeah i tryed the easystart trick as well it will run on easy start but as soon as u stop sprying it will cut out if the immob an ecu were all diffrent would i not get an immob fault?yeah all lights work have had it on a jump pack when cracking aswell.i am going to try and two it for a distance incase it is air locked.

 

[scarble]

I'm sure the air would be forced round and injected out though?
Scope the injectors, seriously.

I assume the immobiliser LED goes solid at ignition on?
Then it.. goes.. out when the engine.. doesn't start? Maybe it stays on until the engine starts, I don't remember. But if it's flashing then it's not disarming. I think.
If the ECU is from the engine and the UCH and immobiliser thingy are from the car then it wont work (I think) and if the ECU is from the old engine and thus matches the UCH and immobilise you may need to program the injectors into it (but I don't think that'd would stop it from starting, it'd just run bad)

Be careful with that easy start stuff, you may end up damaging something.

 

[ali1202]

ok I will hopefully manage to get time to scope them tomorrow. i checked the sequence with the auto data book and it was ok cant remember what it was though think if it goes solid then goes out its ok. yeah not going to mad with It have seen what it can do! if I give the fuel pump cut off solenoid a constant feed to make Shure its open and attempt to start that should rule that out as well? dose the ecu need to see a certain pressure in the rail before activating the injectors or should it give a constant fluctuation signal to the injectors?

 

[scarble]

if I give the fuel pump cut off solenoid a constant feed to make Shure its open and attempt to start that should rule that out as well? dose the ecu need to see a certain pressure in the rail before activating the injectors or should it give a constant fluctuation signal to the injectors?

1. Depends on if the solenoid is normally open or normally closed, applying a current might close it (i.e. restrict flow) or it might not. Also if you apply a constant feed bear in mind that it's probably supposed to be a PWM signal and it can be quite high (6 amps ish?), even with the correct power supply if there's no fuel flowing it'll cook itself, the coil will melt and it'll be fecked.

2.I don't know if it will try to inject with low rail pressure or not.
I don't know what kind of scope you have but bear in mind the pulses will be around 100-300 micro seconds (I think, someone confirm?) so you will need to set your scope up to catch that.

HTH