Wont Start for Love nor Money - Clio 172 Race Cup Car

[Daverb]

Hi all,

Can anyone help with Clio 172 Race Cup car?

Long standing problem - it had the Renaultsport loom and ecu on it and developed a starting fault. It just would not start up.

Thought ecu was at fault so changed to Omex 600. Got it started but its never been easy to start since the problems with the Renaultsport loom in December 2007.

Had it out at Donington park in November. Really difficult to start - turning over and over before starting. In afternoon the car just would not start at all - evenually got it started but was almost going home. Just cranking over and over.

Now trying to start car after winter and it just wont start.

So...car is: Clio Cup Race car 172

Ecu: Omex 600

Loom: Specially made before I bought it loom for the 172. Not a bit of a normal clio loom so obviously not alarm problem etc...

Car loom: The renaultsport loom is still there to work the lights, starter motor etc...

So far I have checked all earths and lives.

Defo getting 12v even when cranking with Omex and switched lives for omex.

Changed TDC sensor today to new Blue type hoping this would cure it - same problem.

On Omex software it shows engine speed - Stat Sync however is Not Synced

Looked in Sync diagnostics part when turning engine over - its registering errors - counting to 4. So its picking up the missing teeth.

Sync is setup with right settings - 2 teeth missing. 57 and 50% time. The table is setup as 5444544454445444454445444544454445 and so on to the end where is has 333 for 57, 58 and 59. I dont know if this is right or not.


Really really, seriously pissing me off - to my mind it should be starting. I think the engine is fucked. With 2 ecu's and different looms I'm not sure if its electrical.

I have changed starter incase it was drawing too much current when starting - brand new starter.

Wiring to alternator, starter and battery checked.

Also did a compression test and all 4 were good and almost identical readings across the 4.

What else mechanical would stop the car starting?

Any ideas really appreciated.

Dave.

 

[franx]

a guy who repairs/builds these cars here in the lowlands mentioned they're alway a pain in the arse to start + once you get it going : DO"NT stop it for a good while, take it for a good run before stopping it again. I guess these cars are overfuelling generally. No help to you but wanted to share something i picked up at the pro's

 

[Jonny1*2]

sounds electrical mate. I'd give Matt at TDF a bell tomorrow. He deals with these quite a bit. Only downside is that the loom is custom, so it will be harder to workout unless seeing it first hand. Hope you sort it.

 

[Fred@BTM]

go see TDF

 

[Cro]

I had to move to a ford zetec blacktop engine tdc sensor for mine to start well. The renault wouldnt give it a good enough .

I'd hit matt too, could well be a map issue

 

[Daverb]

Is tour de force - TDF?

I'm in Fife, Scotland so long way to take it to someone or prob would of a while ago.

 

[Adey.]

I've switched to a new blue sensor on mine and never had a problem, call tdf or even Omex direct?

 

[jack_kemp]

Try calling tdf, but as someone else said, very difficult to say when you have a custom loom without seeing it.

Unfortunately, you're probably going to have to face the drive.

 

[Daverb]

Still having problems with it. It just wont sync.

Actually got it started and running last week so I know the engine and timing is ok.

Just cranks over and over and says Stat Sync off.

Spoke to Omex, Andy suggested changing MX Start time but didn't help. The hols don't help at the moment.

Fooking car. Why did I buy a French car?

 

[Nick r26r]

Is tour de force - TDF?

I'm in Fife, Scotland so long way to take it to someone or prob would of a while ago.

yes tdf is tour de force , worth the drive to get the car sorted out properly , nothing worse than braking down on track

 

[Icarus]

Okay so it looks like you've narrowed it down to a crank sync issue Have you done the basis i.e. scoped the crank signal to see what the ECU is actually seeing coming from the sensor? It could be as simple as whoever made the loom got your crank neg and pos the wrong way around, just as likely is that if they've used the Renault crank sensor there's a solder joint or dodgy crimp somewhere in the loom joining the Renault loom side connector to the two long wire runs that run back to the ECU connector.

We did McRaes 6R4 a while back which had a very similar problem, issue was as simple as the sensor earth (was hall effect crank) had broken through due to none adhesive lined shrink being used to seal the transition (no strain relief).

If you don't have a scope etc. then to rule out any loom issue order up a length of two core shielded cable, a connector from Renault (it comes with tails) and a pair of female econoseal terminals. Make a mechanicaly strong and strain relieved crimp between the Renault tails and the shielded cable, crimp the econoseal terminals to the other end. Depin the existing crank sensor wires from the 36 way econoseal connector for the Omex and replace with your new section of loom, earth the shield to the ECU ground or similar and try and start it. For 20 quid of bits it's not a bad way to check if it's wiring related!

Scotland is a way from us but we get engines and cars flown to us from all over the world. We're worth the trip!

 

[Icarus]

BTW here's the full tooth control table from a map that is currently running a Clio:

5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 4 4 5 4 4 3 3

Can you copy yours or send me the cal. Just spotted you say you have 3 3 3 for 57 58 and 59..........

Also you should have:

Missing = 2 teeth
MX Sync Test = 57 th tooth
MX Time = 50 %
MX Time Start = 30%

I know you've put that above but just double check.

Finally if it's still a no go take the plugs out and see if you get sync off the starter, with the plugs out it'll spin a lot faster and if you have a weak sensor, incorrect gap or poor signal for any other reason it may well sync when spinning at 300 - 400RPM plugs out but won't at 190 - 220 RPM plugs in.

Aside from that you'll have to come and see us!

 

[Daverb]

Hey Matt,

Thanks for replying. I will try taking the plugs out today and see if I get sync.

I do see engine speed and sync errors when the engine is turning over so it seems to be getting some info. Errors seem to be counting to 4. If you move the sensor slightly when adjusting it too the fuel pump runs which means its getting info from it. Maybe not good enough for sync tho. I have reconnected the cables for the CPS - it's fully Omex loom in the engine bay so uses 2 core shielded cable although the cables are pretty small so suppose there could be a problem somewhere along the cable. I have checked it with a wire tester and both cables were ok. I have some Cat 5 cable and connectors for the ecu - I could try making up another cable.

When it started last week I had the starter connected off one battery and the car running off another lol. It was syncing then. Got brand new cables for starter and alternator since but same problems. Wondered if XAP circuit breaker or alternator could be causing problems. Alternator is disconnected but no joy.

Timing alignment was set at 1.75 so thought that would crack it - seen on here last night everyone has it set at 1.70 but no difference.

Tooth control is same as you posted but with 333 at end.

 

[Daverb]

Doesn't sync with plugs out. Stat Sync Off.

The ECU is bolloxed, it's got to be.

 

[Icarus]

Change the tooth control table to what I have posted and try again. Failing that if everything else is good then the only thing left is ECU!

 

[Daverb]

Changed table to what you said Matt.

Also tried new cable for CPS.

Still no joy - Wont sync.

 

[Fred@BTM]

gap on CPS?

 

[Daverb]

Fred,

I have changed Omex jumper and also filed the CPS so I could try moving it closer but no joy.

Under the sync options on the Omex you can view the info as a table or graph. If you view it as a graph and crank the car over - it's fast but you can see it following the graph line.

 

[Laine_16v]

Move the sensor further away, ive no end of crank signal errors and missfires and although im not using omex (i am using standalone...), they all seems to be slightly picky about the signal they recieve.

I unbolted the front sesor bolt and raised the front edge by about 1mm, all missfiring completely gone. Its worth a try.

 

[Icarus]

Gap should be 0.75 - 1mm. If it's a stock Renault sensor with the correct bolts it will be set correctly. Issue comes if someone has lost the proper bolts and mounted it with some that allow the sensor to move away from ideal position.

Do you have a scope?

 

[Daverb]

Well ecu has been away getting tested.

Results - im going to try a Zetec sensor.

The ecu is hopefully on it way back to me. Ordered a sensor. No brackets available so I am going to have to make a temporary one to try it.

Wish me luck...

Ive booked onto RS Trackday on 23rd at Knockhill. If Zetec sensor fixes it I can go. If it doesn't I will be selling my place.

 

[Jonny1*2]

Well ecu has been away getting tested.

Results - im going to try a Zetec sensor.

The ecu is hopefully on it way back to me. Ordered a sensor. No brackets available so I am going to have to make a temporary one to try it.

Wish me luck...

Ive booked onto RS Trackday on 23rd at Knockhill. If Zetec sensor fixes it I can go. If it doesn't I will be selling my place.

Good luck mate! If not, give Matt a bell and get an ec1 fitted

 

[Daverb]

Well don't want to jinx it but it started with the Zetec sensor - touch wood.

It's running a bit funny - doesn't want to idle and races away if you push the throttle to try and hold it revving at a constant speed. Need to try and get that sorted but it was doing it when I got it started a few weeks ago so something I have done over the winter.

 

[Adey.]

yeah just had to swap to a zetec sensor on mine after the blue tdc sensor failed

 

[Daverb]

Running funny - was settings I had changed on Omex over winter to try and get it running again.

Mainly Idle Fueling. The start map from Omex says to have the Idle Fueling table at 0 so I did this with mine. Put it back to how it was and it was fine again. Bit stupid on my part - the standard car has a idle valve doesn't it - my car doesn't so the car can only control idle with fueling.

 

[Jonny1*2]

Glad you've got it sorted mate. Get some piccys up

 

[Laine_16v]

Adey / Daverb where did you get the brackets that allow a zetec sensor to fit the JC5 gearbox? and do you have a link for the specific sensor you used?

im having to run my blue plug sensor with 1 bolt in to allow some adjustment to get a reliable signal, not really a permanent solution and i want to move over to a zetec sensor.

Also dave ive seen the Omex scatter spark control idle and cold start revs impeccably on throttle bodied clios, have a look into that.

 

[Cro]

I made mine using the old tdc sensor Laine and chopping the sensor part off then making a curved indent for it to sit in the right position and using a small 'U' shaped bracket to hold it tight in. The sensor came from a focus blacktop engine

 

[Laine_16v]

Ive got 2 old sensors knocking about, time to get creative

 

[Daverb]

I did pretty much the same as Cro-Clio - used a old sensor and chopped the sensor off just leaving the bracket then attached a L shape bracket to it and bolted the Zetec sensor to that.

I have the part no - can post it up later.

 

[Laine_16v]

How did you figure out the sensor gap, trial and error, space it off the L bracket with washers? Dont suppose either of you could get pics?

 

[Cro]

I might have an old pic before which will give a general idea dude

 

[Daverb]

How did you figure out the sensor gap, trial and error, space it off the L bracket with washers? Dont suppose either of you could get pics?

I had another Renault sensor and made the bracket so that the Zetec sensor would be sitting in the same place as the Renault sensor.

This was a gamble because the Zetec sensor might have needed to sit closer or further away but the car runs so it must be ok.

 

[Daverb]

Wtf?

Today started it again. Last time was Monday night when all was well.

Started. Idling away. Pottering about and car cuts out. Strange I think and go to restart it....won't start.

Pulling my hair out all day it looks like the ecu isn't earthing the fuel pump blue/White wire. This controls the main Omex relay (injectors and coil) a fuel relay and a power steering relay. Ever since I've got the Omex it runs this lot for a second when the ecu gets power and then constantly when the engine runs. Now it doesn't do this.

The fuel pump does have a seperatate driver in the ecu so it's packed in I guess.

 

[sideways danny]

depends how it's wired. A lot of installs just used the standard fuel pump relay and leave the stock ECU triggering the fuel pump

take a look at the wiring loom under the fuses and relays. I've seen a number of these over heat and partially melt, normally down to corroded terminals