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Wobba
29-11-2012, 10:59
Same as before. Electrical in nature, can hear the relay in the engine bay clicking when it misses. It has been like this for some time, on and off. I've replaced:

Coil pack (Megane one)
Spark plugs (several times)
Crank sensor (twice)
TPS (special one for ITB's/Jenveys)
Rewired crank sensor
All relays replaced
ECU sent to Emerald ECU's for testing (was some scrambling to code due to some kind of electrical interference)
Swapped to Walbro performance fuel pump
Rewired pins for power and crank sensor on ECU harness
Rewired main wiring for ECU/Ignition/Fuel pump relays

I've had a leaky camcover for ages, it is NOT the seal or the head itself as both been replaced and it still leaks into spark plug well no.2 This itself fouls the spark plug and causes a loss of power and generally rough engine revs. I had a theory the spark from coils could have been discharging through the body of the car causing damage somewhere as the oil levels in the spark well got very high.

It could be something shorting out, or an old part of the wiring loom I have not checked I guess.

I have no problem starting the car and it does not happen when I just start the car from cold, it only seems to be when hot usually.

I cleaned the oil out the other week and last night and replaced plugs last night again but although it felt nicer to drive, the misfire started again on the way to work.

Might take it to Emerald themselves and let them play with it, this is doing my nut in! Always happens when I least need it to happen as well...

Wobba
29-11-2012, 17:32
I know it must be something simple that I have missed, damn frustrating though when I currently rely on car for transport!

Wobba
29-11-2012, 17:33
Could a dodgy immobiliser cause it?

Wobba
29-11-2012, 20:17
Started car up and let it run for a bit at work before I went home. I grabbed a handful of wiring loom and shook it about. There was a distinctive change in revs sometimes when moving some of the cables and I thought I got the relay to click once or twice when wobbling it about. I thought it might be injectors but the misfire persisted even after unplugging each of the injector power supplies.

I am SURE this is a wiring loom issue, could be shorting out on another wire or causing interference to the ECU power supply somehow, or crank sensor.

I'm going to take it off and take it apart and check it completely. I'll rewire it some nice colours too :D

Off to see another car on Saturday over in Bristol, 0217 might have overheard this and has started misbehaving in protest! I will fix the little ****er for good this time!!!

stevie_b
30-11-2012, 11:04
Off to see another car on Saturday over in Bristol

What's that then? Spill the beans ;-)

Wobba
30-11-2012, 11:26
8) :affro:

16v_paddy
30-11-2012, 18:54
There's a wire on the loom somewhere that I know can cause problems if it goes anywhere near the crank sensor wire, ****ed if I can remember which 1 it is though

Wobba
01-12-2012, 01:32
Might be something like that.

icenutter
01-12-2012, 13:08
Hopefully you've found the solution to your problems!

Wobba
01-12-2012, 19:05
Well, I ripped the alternator out and all the ECU loom and pulled it apart. No clear issues but I moved the crank sensor cable away from all the others. Gave up for a bit as it was raining hard. All back together, new alternator on, which blew up the first time, was repaired, refitted and showed regulator issue. Electrician said the regulator wires were wrong way round so I swapped em and rewired it. Went for a start and battery warning light is on, meaning no feed to battery...this will be the 5th time I've swapped that new alternator out.

Up at 7 am to go see another car for sale in Bristol. If it keeps misfiring after this and I spend ages ****ing about with the alternator again...and I buy this car tomorrow...I might break or sell the Clio. I really mean it this time, I am tired of stupid problems that are so hard to find and working in the rain/cold/snow/dark. Otherwise I will put it in a garage and strip it for trackdays and let someone fix the electrical issue for me.

icenutter
01-12-2012, 21:06
Perhaps when you have another (reliable) car on the go, then you'll have more time to sort out the Clio? I know when ever I need to fix a car, to go to work or something, it always goes wrong.

Keep the faith.

northy
01-12-2012, 22:05
Sometimes the air box can squash the wires in the loom. Give it s try without the box and see if you can replicate the fault!

16v_paddy
02-12-2012, 00:23
Sometimes the air box can squash the wires in the loom. Give it s try without the box and see if you can replicate the fault!

If his airbox is squashing any wires round that area he's got much bigger problems, like someone stole his jenvey's :lol:

jock
02-12-2012, 01:40
If his airbox is squashing any wires round that area he's got much bigger problems, like someone stole his jenvey's :lol:

LOL , some one needs to steal the whole thing.....:winkey:


then mine come to think of it :evil:

stevie_b
02-12-2012, 09:50
Perhaps when you have another (reliable) car on the go, then you'll have more time to sort out the Clio?

This. Even if no more time to fix it you will find it a lot less stressful when you have something else you can rely on. I had a 405Mi16 that I used to sprint and hillclimb and it broke down near enough every time I went out in it (which admittedly was either on track or driving it to/from the track) so much so that the AA wrote to me and said that they weren't going to pick me up any more. I could just about live with it though as after it was dragged back home I could just put it back in the garage and fix it in a few days' (or weeks') time - if I had been dependent on it for the school run or to get to work or something it would have been an absolute nightmare. Even today I feel stressed when the wife's car starts playing up as it's so crucial to day-to-day life for her and the kids (I manage with my bicycle for most of the week) and neither of us are too keen on her using one of my cars for family duties so hers really needs to be running well 100% of the time, which is difficult to achieve. I'm sure once you have another car you'll feel a weight off your shoulders and can get on with getting everything sorted in a more relaxed frame of mind, and enjoying the Clio more on the times you do decide to use it (rather than being compelled to use it). Stay strong.

Wobba
03-12-2012, 10:58
I went out at 7.30 in the freezing cold on Sunday morning. Tightened a screw on alternator and rewired the regulator wires back to the OE fitment. The dash light now does not come on for the battery, which probably means the wires are the wrong way round. With them the other way round, the way I rewired them the night before, the battery warning light is always dimply lit.

Car STILL misfired a few times on the way in to work today. Same as before.

Last time I installed this alternator it was reading very high output, like 16.5/17v on the battery terminals. I now get, with the same setup, only 11.7v.

I think tbh at this stage I am going to give up and leave it with an auto electrician or something as this is completely doing my nut in.

stevie_b
03-12-2012, 16:50
Was the car in Bristol any good?

sideways danny
05-12-2012, 01:45
I went out at 7.30 in the freezing cold on Sunday morning. Tightened a screw on alternator and rewired the regulator wires back to the OE fitment. The dash light now does not come on for the battery, which probably means the wires are the wrong way round. With them the other way round, the way I rewired them the night before, the battery warning light is always dimply lit.

Car STILL misfired a few times on the way in to work today. Same as before.

Last time I installed this alternator it was reading very high output, like 16.5/17v on the battery terminals. I now get, with the same setup, only 11.7v.

I think tbh at this stage I am going to give up and leave it with an auto electrician or something as this is completely doing my nut in.

I've seen endless problems with reconditioned alternators. the regulators they use are all crap. Burpspeed racecar went through 5 alternators in the first half of their first season before buying a new one from renault which has been fine for over 2 years now.

Evogone
07-12-2012, 01:02
ECU voltage is another issue, fluctuating voltage cause all sorts of issues even if voltage comp is inc in map.

Wobba
07-12-2012, 11:57
It's either crank sensor signal being lost or a shitty power supply to the ECU I think.

Wobba
07-12-2012, 11:59
The 'new' alternator has been removed again as it was not delivering power. Old one back in, runs okay even with misfire. Not going to mess about with it anymore, I'll take it to Emerald possibly as I just want it sorted.

andreas395
08-12-2012, 16:50
That's crap mate not been online for awhile and you still have problems :( hope you find the fault soon

Wobba
08-12-2012, 17:44
I'm close to sorting it. Coming home from Surrey Rolling Road today after a dyno test, it had the battery warning light come on a load as well. Went away as I reduced speed though...new alternator ordered!

Also, found a short from the alternator at the dyno session. It was misfiring like a bitch on the way up, but misfire went away on the way home. Weird!

I will run a permanent ECU live I think, with a switch in the cabin, and possibly for ignition too.

andreas395
08-12-2012, 17:58
That's good to hear 8)

16v_paddy
09-12-2012, 02:48
Having drove this car today I'd say it's still well worth getting to the root of this problem so don't give up :winkey:

& for those not in the know, it's absolutely fcuking bonkers, full on batshit mental

sideways danny
09-12-2012, 17:51
too much powdercoating stopping decent earths still. Did you ever replace that nasty rose joint bracket on the alternator?
Refurbed alternators use crap regulators, new Valeo will help lots
Also, get rid of that awful ECU

northy
09-12-2012, 21:18
Nothing wrong with the emerald ecu! I'm a big fan of Dave walkers work!

Wobba
09-12-2012, 22:57
The guys at Emerald have been top lads as well. The ECU is fine, the GUI is from the days of the ZX81 though lol.

The new alternator and the old one have now given up the ghost so a new Valeo is on the way. The earthing was screwed up with the powdercoated PS pump bracket from the alternator, and yes I still have the rose jointed bracket setup.

No misfires today but the regulator on the alternator finally gave up as I am now getting 17v off it.

Wobba
09-12-2012, 22:58
Having drove this car today I'd say it's still well worth getting to the root of this problem so don't give up :winkey:

& for those not in the know, it's absolutely fcuking bonkers, full on batshit mental

I am glad you enjoyed your slice of batshit cake Paddy ;)

jock
09-12-2012, 23:48
& for those not in the know, it's absolutely fcuking bonkers, full on batshit mental


LOL:lol: love it!

DSilvaSport
13-02-2013, 16:56
Wobba, I'm assuming you've had it plugged in for diagnostics and found nothing? ..I had a similar problem years ago, drove me crazy for a while - Renault plugged it in and it was just CTS, although I saw somewhere else you say yours is virtually new.

You're only 20mins from me - if you think it might help you can come and swap any part you like with either of my cars to see if it eliminates the problem and identify the culprit. An option.

Wobba
14-02-2013, 01:53
Hi, thanks. I have already tried two new CTS's. It is not a sensor issue as my car can show me via laptop all the sensor readings and I can control them and unplug them etc, no change. I've ruled out the crank sensor and the wiring loom for that too. Will rewire the throttle position sensor soon though.

I suspect this is a deep wiring issue, on the loom. If it isn't it will be a bizarre problem wit an injector or some kind of fuel pump or ignition barrel wiring or immobiliser issue. Hard to find.

DSilvaSport
14-02-2013, 02:05
Yeah, I just managed to see the vid you posted and read through some of this thread. Don't forget to check the vorsprung manifold sprocket dongle! What a mission.

Smokey McPot
14-02-2013, 08:36
Won a, would it not be easier to make a new loom than chopping and changing the existing loom? Better to start afresh.