Rough running engine.

[Spitfire6]

Hi,
For the third time in four months, the car has developed what feels like running on 3/4 cylinders.
It has had new plugs fitted after the first time.

The first time it started about 10% into the drive home and was OK in morning.
Plugs were changed.
Second time it started on the way home after driving for ten minutes and to home 5 minutes, and was ok again in morning.

Now it has been like this for 2 days; to and from work 10 miles.

It feels like one cylinder is not working and intake noise is louder than usual. No real power and must use the gears to keep going. idle speed does stabilise to normal.

I have no engine kaput light illumination, only on key start/lamp test.

Something simple? not coil pack or injector?

Cheers,
Iain.

[GrandadMonkey]

You are using Bosch (or Peugeot) branded spark plugs aren't you. These cars don't seem to like NGKs.

Fuel? I use only Shell V-Power Nitro+ or BP Ultimate. I never use supermarket stuff.

[Spitfire6]

Hi,
I normally use NGK, have done for nearly 30 years on cars I own.
The original plugs on the car were NGK LFR5B's. They did look worn n old with a light dusting of ash.

Following the advice on here they have been replaced with Bosch FR 78 NX plugs. Makes sense to use the quad type as I do not want to be removing them again for a while...

I use good fuel.

This morning the car was fine again. Later when I went out again the car was running on three and after a couple of stabs on the throttle the power came back and all is ok again.

The way I see it is that it's fuel or ignition (electric) related. I can easily pull the coil pack off and put 4 plugs in to it and ground them all to earth to test the ignition side. I can pull the connectors off the injectors to find a non squirting injector. Of course only when its running like a bag of ****.

Is it possible for the ECU to log faults without the engine fault light coming on? If so I can connect my scary1 tool!

Cheers,
Iain.

[Capncol]

Is it possible for the ECU to log faults without the engine fault light coming on? If so I can connect my scary1 tool!

Yes. Having said that you would normally get an antipollution fault warning unless it was something like an air leak or poor injector spray causing an over lean condition. That would set up a fault such as P1380 (misfire detected)

[Spitfire6]

Hi,
I had a TerraClean a few months ago. Made no difference to performance or Economy of car, but would hope it at least cleaned the injectors..


Wish I did not have this loss of power. That happens random.

I wish the fault would stay and I could fault-find and locate it.

Catch 22

Cheers,
Iain

[gazza82]

Without checking the fault codes it's impossible to say for sure but I'd put a few bob on the coilpack is failing.

[Spitfire6]

Looks like scary1 is being installed on an old 32bit xp machine.

Cheers,
Iain.

[Spitfire6]

Hi,
Bought a new coil pack for 43 quid off EBay and fitted it in about five minutes. A little silicone grease and a squirt of WD40 in the primary connector.

Car is running fine now. Thanks to all for your time.

Strange I never had an engine fault illumination.
I have still to install the scary1 sw as 32 bit notebook kaput. I hope to install it on another notebook borrowed and see in any history present.

New Question:
the coil pack has 4 terminals. Expected 5 or 3..
Does the ECU fire 2 plugs at a time?
Does the ECU swap polarity on the coils so it always fires the plug that's on compression the correct way?

I will be taking it to work to check it with a multimeter and maybe answer the above questions.

Again,
Cheers,
Iain.

[tenpole]

I fear I have a similiar problem with my 206cc not firing right.

[GrandadMonkey]

Use of non-Bosch or non-Peugeot branded spark plugs has been known to spike the coil pack on occasion on these cars. Glad you've sorted yours now Iain.

[tenpole]

Will check the spark plugs and report back.

[Spitfire6]

Hi,
The old coil pack is deceased.
The secondary resistance between 1 & 4 is way too high. Burnt out I would guess.

I found a schematic of the coil pack it shows the coil pack to fire two plugs at the same time. AKA wasted spark.
It shows the primary as three connections to primary.

If the 206cc 2l 16v coil pack is true "wasted spark";
you need to periodically swap your spark plugs over i.e 1 to 4 & 2 to 3. If you do NOT do this-
Do Not WASTE your money on expensive plugs.
If you do not swap your plugs, two will wear out much faster than the other two.
Even so, two of your expensive plugs will never be fired properly, negating the fact they have expensive metal on the centre electrodes.

All the above factual statements are based on the schematic I have seen for the coil pack. If I have looked at a wrong one and actually four primary terminals are utilised then with some clever low voltage switching being performed by the ECU then the above is erroneous.

For now I stick with my recommendation of swapping plugs periodically or buying cheap plugs and changing them all periodically.

Cheers,
Iain