renault 19 problems

[exxos]

HI all,

I have a N reg renault 19, 1.4 petrol, seem to have nothing but trouble of late.

To cut a long story short, I've replaced, HT leads, cap as I found that the cause for a few running problems. Ran bascially fine for 6 months. now refuses to start.

After a week of investigation, there is a small box with seems to be a air shut off relay. There is no mention of this in the book at all. It never clicks when its on the car, the relay itself works as I have tested it (im an electronics enginner so easy to test) that works fine. I traced the wires back to the ECU and everything fine there also. So assume the ECU is faulty.

I unpluged the air pipes and the car started pretty much first time this past week. It idled a bit high but wasn't too serious, Though now it refuses to start again. It does not even try to start. The only way now to start it is by holding the gas peddle to the floor, eventually it fires and tries to start. It runs and miss-fires like crazy but at least it starts. When its been running a few moments the car runs great...

...Well apart from a strange cut of problem, now the past months I have tried to work it out with no luck. the ONLY time it cuts out is when you go from 80mph to 60mph in gear but slowing down, IE, comming up to a island. If you slow down in gear then go into neutral it cuts out right away. Once started again it does not cut out again ( at that point).

Now if you slow down to 40, it does not cut out, though hard to say for sure as the engine is turning over in gear anyway, going straight into neutral does not cut out at all. Slowing from say 50 to 30 in gear never cuts out.

With that air relay left off, the carb sucks in more air, idle speed is pretty high, it runs smooth, so you would think there would be no way it could cut out, but it does! but only when slowing from 80 to 60!

There is an idle speed control motor, this appears to be working fine. There is always petrol being pumped. the only confusing thing, is when the carb butterfly is closed, I can't see how any petrol gets into the manifold for it to idle. This air relay goes into the back of the manifold so understand that..

Also tried to fool the thing and alter the accelerator cable so it keeps revs up that way, keeps the butterfly open slightly so more air and petrol can get though. Still does not matter, still does not start and still cuts out exactly the same.

I am pretty sure the ECU is duff at this point, its not turning on the relay, which I assume to be part of the automatic choke, so wouldn't be supprised it at some point the ECU just decides to turn the fule off or something. If anyone has a ECU or a referb then please let me know. Its either that and/or replace the carb assembly with all the sensors.

If anyone has any of those parts then let me know, if anyone has any ideas on anything I have not checked or anything I else I can do then please let me know.

Thing has been driving me nuts these last few months :-(

cheers,
chris

[Chris H]

I still can't figure out what relay you mean? Where is it? Only thing I can think of anywhere near this is the charcoal canister solenoid.

The injector will fire all the time, at idle the betterfly will have a film of fuel on it.

I doub the ecu is duff as they in all honesty never go wrong unless theres been welding on the car or broken earths.

Have you checked the earths?

Does it spark when cranking now? If it has a rev counter does it jump slightly when the ignitions on? If not the ignition module might be dead, common problem these days. More and more are failing.

[exxos]

the relay is a small black box with 2 air pipes, its right next to the carb, one pipe goes to the fule pump, I really have no idea why as seems to do nothing, actually assume its air... the other pipe goes behind the manifold. When you unplug it, the car's revs go up a fair bit but thats about all. I found in leaving the pipes disconnected the car would start fine... well it did for a week at least... There is no mention of this box in the book, would it help if I took images of the thing ?

If you then close the pipes off again while the engine is running, the revs almost die to nothing, then I think the idle speed motor adjusts and brings the revs back up again. you can hear the motor running, I even left the thing totally off for a test, and the revs kept going up and up, so turned the engine off quick before it got *too* quick. Not even sure what its actually controlling, theres just a little "V" shape bung on the end, cleaned it all up though..

I think the injector fires all the time, when you leave the car off for about 30 seconds, The idle motor seems to open fully up, when it does that, when you turn the ignition on the injector fires once. then while turning over it keeps firing. If you turn the ignition off and try a re-start, the injector does not fire that first time, not unless you wait another 30 seconds.. Probably nothing wrong there, just trying to get my head around the car's startup sequence..

I messed with 2 earts, the one on the HT coil, and another near the carb.. might have missed some somewhere though.. I am wondering if the HT coil is actually firing while trying to start, will try and check that at some point.

While turning over it seems to open up the idle motor, I assume letting more air though, and it idles high for about 30 seconds, then the motor buzzes a few times and the idle speed drops down a few times and settles down.

Its really strange this car is, never known anything like it, I mean its got plently of air and fule, in fact you can smell the petrol while trying to start it, its like the HT is not firing.. Though saying that it only trys to start if you push the accelerator pedle right to the floor, then it missfires like crazy but you can get it start that way eventually. Just turning over does not do a thing, it does not even try to start.

Saying that, I can drive 40 miles and the car will run fine apart from cutting out. I can leave it 2 hours, get back in and it will start first time. Leave it standing 8 hours or more and it won't start.

thanks,
Chris

[Chris H]

thats the charcoal canister solenoid. It goes tot he charcoal canister which has a breather pipe from the filler neck of the tank.

For it to activate the engine needs to be up to temp, blip the throttle and release and it will activate.

the way the throttle body behave on turn off and start up is fine.

It sounds like its either the module or the crank sensor or the coolant temp sender.

What earth on the HT coil?

On the gearbox end of the engien beside the dizzy there is 2 electrical plugs intot he side of the head, the one with the white plug, unplug it and try ansd start it.

[exxos]

OK, thanks, will go out in the freezing cold and have a look and a fiddle. will report back in a bit.

[exxos]

*shocked look*

There was 2 connectors, unpluged the white one, car started second turn over of the engine, car steady in idle speed. what on earth is that sensor for ????

this has been driving us nuts for months, my father just stood at the window with his mouth tot he floor as it started first time in all this cold. The car is parked on the drive all night so pretty frozen up!

*amazed*

Chris

[Chris H]

coolanrt temp sender. Get a new one from GSF or similar.

12 quid ish.

[exxos]

according to the book, the temp sensor is on the left connector, theres an arrow pointing to it, (black plug) the one I unpluged is the white one, Is that the crank sensor ?

Chris

[Chris H]

did I not just tell you its the coolant temp sender? yes I did indeed.

[exxos]

Ive taken a scan of the book.

http://www.cps-electronics.co.uk/temp/sen1.jpg

The one it points to is the connector on the left, I unpluged the one next to it (white one on the right).

How does the temp sensor prevent the car from starting ? we can't figure that out either :-(

[Chris H]

ahh the haynes, waste of good recycled paper it is.

The brown one is the temp gauge/light sender.

The white one is the coolant temp sender.

The sensor corrodes and gives erroneous outputs, easily checked with a multimeter or iif your anal a scope.

Yours has most likely failed so as to read its hot when its not. This cuts back injector duration thus less fuel when its needed.

Thus in technical terms, no worky

[bbracer16valver]

its a renault

[exxos]

ive unscrewed the thing and water is leaking out of the hole, I wonder if one is water and one is oil or something....

[exxos]

Originally Posted by Chris H

ahh the haynes, waste of good recycled paper it is.

The brown one is the temp gauge/light sender.

The white one is the coolant temp sender.

The sensor corrodes and gives erroneous outputs, easily checked with a multimeter or iif your anal a scope.

Yours has most likely failed so as to read its hot when its not. This cuts back injector duration thus less fuel when its needed.

Thus in technical terms, no worky

lol, I think your right, after reading a lot about the fule system , it conflicts with what it says even in the same paragraph! Will try and get a new sensor.. thanks!!!!!!!!!!!!!!!!!!!!!!!!

[Chris H]

again i have already told you what they are.

They will both leak water out as they are both into the water jacket.

[Huw]

Originally Posted by exxos

ive unscrewed the thing and water is leaking out of the hole, I wonder if one is water and one is oil or something....

As Chris H sais, they are both temp sensors, one feeds the ECU and the other feeds the little dial on the dash.

[exxos]

with it now, been out to get a new sensor, fitted it. Will see how things progress over the next few days. Have loads of little jobs to do on this car yet, nothing majour though..