Hi Chaps,
Happy new year to all ......
Funny thing this morning with SWMBO's Megane (1.6, 8valve with 38k,).
She started the car up and it apparently ran very roughly, didn't tell me of course - just revved up and drove off. There is quite a steep hill near us which she struggled to make 20mph up, turned around, came home, blamed me and has driven off to the sales in my Omega.
I've now taken the car for a spin and can feel nothing wrong with it - except a very, very slight misfire thats only noticible with your head under the bonnet. The plugs are fairly new six months or so, but the car has the original HT leads - which I have now sprayed with WD 40. Although its bucketing down, the engine is bone dry and the HT leads seem in good condition despite being almost 5 years old. I have to say that the HT leans don't seem that tight a fit on the top of the plugs - they pop into place but there is some movement.
The car was last run on Boxing day a 200 mile return trip with it performed faultlessly.
Any ideas? Does anyone have any experience of the 1.6 8V Megane that might help. My next step was to start her up from cold tomorrow morning and then to replace the plugs and HT leads.
In anticipation.
Robert
|
Well of course it's your fault!!!
Does your mrs know MY mrs? That sounds exactly the same sort of logic as I get. YOU wanted to take HER car all that distance, YOU must have broken it...
|
We have one of these in our family, 98 S 1.6 8 valve, 48000 miles. I've heard that a common failure at this kind of mileage is the coil packs - these engine run with twin coil packs mounted on top of the rocker cover. The symptoms sound suspiciously like coil failure. I'd check these out, they look easy to replace. Please can you post a follow up when you've sorted it, am keen to know the outcome!
Baz
|
Thanks - sounds worth a try. The coil packs are on top of the rocker cover - with very short HT leads down to the spark plugs. I'll be making a call to my Renault dealer & a factors tomorrow - if this gets too bad it could be a pooly cat as well.
Regards ....... Robert
|
Robert,
Don't go buying coil packs to replace at random just yet.
Try the cheapest option first.....Remove and examine the rubber vacuum hose from the inlet manifold to the MAP sensor on the bulkhead. Check for splits that may only show up when you bend the hose.
I've had two of these to replace on Megane's this month. This pipe is quite stiff and short on the Megane, at certain engine positions the split would open and ruin the MAP input/mixture.
It was happening the most when you were drifting through town at low revs and then tried to pull away, you know how that makes the engine rock on the mounts. Once you had reached a cruising speed, or when revving it hard, the split stayed closed and all was well.
Another symptom was them sounding like they were missing on one cylinder at idle.
They drove so badly at times you could have told the customers they needed hundreds spending but in reality a few minutes and 200mm of small bore hose cured it.
If the hose is OK then I would double check/replace the plugs, then the ign leads.....leaving coil packs as a final concern. But in any case do get it properly diagnosed before you spend a lot on parts.
Also has yours had the modified valve cover gasket yet? They had problems with these leaking oil into the plug wells. It caused oil and muck to build up that could cause misfiring. The Renault updated item is under a tenner and easy to fit.
HTH
MM
|
|
Thanks MM - I'll take a look ......
|
|
|
Hi,
I've just checked it over. The hose seems to be ok - if its he one that is about 20cm long with a 90 degree bend at each end. I havn't taken it off as it seems very firmly attached but the rubber seems in excellent condition.
I also looked down into the plug wells - no sign of any oil seepage. Our car was one of the very last 8v's and hopefully they would have sorted that by then.
I'll go for new plugs and HT leads tomorrow - any idea of the cost of the leads, HT modules and rubber hose?
In anticipation.
Robert
|
Robert,
Your hose may be perfect but check with it off before you spend any cash on leads etc.
Get a small screwdriver or knife and lever off at the ends, they are only a tight push fit.
On the two I dealt with the hoses looked perfect at rest...the cracks were on the insides of the 90 deg bends and only opened up as the engine rocked.
That's why the engine misfire was variable because the air leak only happened when the engine took up a certain position under some types of load.
MM
|
MM, thx for your useful post. A problem with my Megane, maybe you can help here too - the idle speed is sometimes very low, particularly when cold, during say the first half mile. It's started stalling at junctions etc. Also sometimes when hot the idle speed drops away but usually comes back to about 750 rpm. Otherwise running perfectly -any ideas what to check?
Cheers
Baz
|
|
|
Hi MM,
I've removed the hose, cleaned it and unfortunately the condition is perfect, no cracks when the bends opened out.
New set of plugs & HT leads next I think.
I'll keep you posted.
Regards .......... Robert
|
Sorry Robert, I was really hopeful you may have found this hose was going to be a simple cure.
Worth passing on the advice I had from Andrew Moorey (Tune-Up) who posts here when I mailed him about this Megane fault before I'd seen the first vehicle.
"Throttle position switch sounds a likely culprit especially as it is at very light throttle openings. Try disconnecting it. Other possibilities could be O2 sensor or tracking around the plug leads or coil packs"
So he mentions leads, coil packs as well plus a couple of other items.
Actually apart from the MAP hoses and valve covers these Megane's have been quite good for engine reliability. Having said that the higer mileage one looks like the head gasket is just starting to go at about 55K.
MM
|
|
|
|
|
|
|
