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View Full Version : Serious juddering when i apply any throttle whilst cruising?



gignwah11
10-01-2014, 09:13 AM
Hello,

If i drive round with only just the lightest of throttle its ok but when apply the throttle it judders and it gets worse the harder you apply the throttle. Its been getting worse since i bought it a few months ago, it had been sat for 2 weeks prior maybe it needs a dam good thrashing? Any ideas - spark plugs are not due til 90k i think and i'm on 60K (04 reg) i'll check the HT leads at dinner time. I also noticed that the battery light flickered on for a second (whilst on motorway with the judder) and then did not come back on but that might be me just nursing it to work. Is it going to breakdown on me?

ian w
10-01-2014, 09:32 AM
Hi
The battery light flicker is a normal thing for these cars so don't worry. the judders when applying throttle sound very similar to mine when I purchased it and it turned out to be a failing coil stick. I ended up buying a code reader to find the faulty cylinder replaced the faulty coil and all the plugs at the same time, no problems since. mine never broke down but got worse until the mil warning light came on which I think was caused by me giving it a thrashing on the way home from work.
the obvious question is there plenty of fuel in the tank fuel gauges on some cars are not accurate others are very good.


cheers Ian


Ian

gignwah11
10-01-2014, 09:39 AM
Thanks for the info - Battery light sorted now i have to find my OBD reader in the garage (messy) where is the OBD socket hiding on our cars?

There is a third of a tank in it i never let it go down past the last line to risky with our gas guzzlers! I'll fill her up and see on way home later.

ian w
10-01-2014, 03:01 PM
Hi obd connector is down to the right of the steering wheel under the dash.

Ian

Ken B
10-01-2014, 05:45 PM
Sounds like a mis fire not surprised with all the dampness recently. Mine suffers with water dripping onto cylinder No 8 from the screen washer jet, this got down the plug hole and shorted it out. Since I've been using mine to and from work daily its been fine and no misfire . Our cars don't like being left especially in the rain for to long, mine certainly dosent.
Hope u get to the bottom of the problem

stevenw
10-01-2014, 06:08 PM
Sounds like a mis fire not surprised with all the dampness recently. Mine suffers with water dripping onto cylinder No 8 from the screen washer jet, this got down the plug hole and shorted it out. Since I've been using mine to and from work daily its been fine and no misfire . Our cars don't like being left especially in the rain for to long, mine certainly dosent.
Hope u get to the bottom of the problem

i take it you've removed the under bonnet felt as this normally soaks up the water.
I had the same problem but I think it was cylinder no.7;I put a little bit of plumbers mait around both washer jets and don't get any leaks now.

Ken B
10-01-2014, 06:15 PM
i take it you've removed the under bonnet felt as this normally soaks up the water.
I had the same problem but I think it was cylinder no.7;I put a little bit of plumbers mait around both washer jets and don't get any leaks now.

Yes I have removed the insulation and if not raining this weekend will seal them up, cheers Steven

gignwah11
10-01-2014, 09:48 PM
EML light came on today - i have plugged in my elm327 running EasyOBD and it came up with a fault but no code just 'pending PTC' so reset it and i'll take off the insulation and seal up the washer jets.

Phoned Austins and i'm booked in for the 8th Feb for a good seeing to :)

Tim
10-01-2014, 10:42 PM
Take it over to Dom for a second opinion Alan, it could be several things both electrical or mechanical.

Herman
10-01-2014, 11:11 PM
Coil pack or plug would be my first guess

AndyG
10-01-2014, 11:28 PM
Also worth checking the Air Filter and MAF.

gignwah11
11-01-2014, 12:06 AM
saw Dom today and he suggested coil pack and the OBD scanner would say which one it is so when i plugged in the ELM327 scanner and said nothing i was surprised (this was after i saw Dom).

Anyway downloaded the other OBD software digimoto seems more detailed than my simple Easyobd and wait for it start juddering again and see what it says then.

Ken B
11-01-2014, 01:28 AM
With the misfire I had recently I had no mill light warning and after looking found puddles on top of no8 coil pack . the misfire I had on my previous car did put the mil warning light on and the snapon diagnostics kit said low speed misfire on cyl no 5. I swapped the coil with another cylinder and cleared the code, rechecked and the fault stayed on cyl 5 shanged the plug and this fixed the misfire.
Dosnt seem to take much to stuff up a plug on our cars I would change the plugs anyway and if you do do not overtighten them as the plug threads are a week point on these engines. Good luck

brrm
11-01-2014, 01:42 AM
It took a long time for my misfire to register with the MIL light - in fact it only lit up the light when the coil pack failed entirely and the car was firing on 7 cylinders all the time.

stevenw
11-01-2014, 07:05 PM
Just developed a slight judder at around 1000-1500 rpm on my 260.

Took all the COPs of to inspect them and found cylinder no.2 had some dampness around sparkplug area and on lower rubber boot of COP.No sign of where the damp came from.

Dried it off put back together-all running fine now.

It's a very easy quick thing to check.

I use a 7mm hose clip driver with a flexible shaft so you can get all the COPs off without having to remove anything else except the air inlet tube to the throttle body.

Just unclip the electrical connector to the COP,undo the 7mm head bolt holding it and carefully pull the COP up.Leave the small bolt sitting on the COP when removing and replacing otherwise you may drop it and lose it.

Just do one at a time and put it back and reconnect electrical connection before moving onto next one,but be VERY careful not to drop the little bolts.

AndyG
11-01-2014, 08:04 PM
............,but be VERY careful not to drop the little bolts.

Or get a pair of thin, very long nosed pliers. Been there, Got the T shirt :ash

Herman
11-01-2014, 08:22 PM
Just developed a slight judder at around 1000-1500 rpm on my 260.

Took all the COPs of to inspect them and found cylinder no.2 had some dampness around sparkplug area and on lower rubber boot of COP.No sign of where the damp came from.

Dried it off put back together-all running fine now.

It's a very easy quick thing to check.

I use a 7mm hose clip driver with a flexible shaft so you can get all the COPs off without having to remove anything else except the air inlet tube to the throttle body.

Just unclip the electrical connector to the COP,undo the 7mm head bolt holding it and carefully pull the COP up.Leave the small bolt sitting on the COP when removing and replacing otherwise you may drop it and lose it.

Just do one at a time and put it back and reconnect electrical connection before moving onto next one,but be VERY careful not to drop the little bolts.


When putting the COPs back, apply some dielectric grease around the end of the rubber boot (inside) and the connector. It will help to keep the moisture out.

Tim
12-01-2014, 08:00 PM
Herman whats "dielectric grease" and where do you get it, thinking I could use it on the bike as I'm sorting the ignition system out. Got moisture somewhere. :(

Herman
12-01-2014, 08:12 PM
Herman whats "dielectric grease" and where do you get it, thinking I could use it on the bike as I'm sorting the ignition system out. Got moisture somewhere. :(


What it is
http://www.ehow.co.uk/how_7582358_use-dielectric-grease-connection-sealing.html

where to buy
http://www.ebay.co.uk/itm/Dielectric-Grease-for-contacts-and-connectors-/380370452070

Tim
12-01-2014, 08:41 PM
Nice one thanks.

Peter Garton
18-01-2014, 07:32 AM
I have followed this very informative thread with interest. Our ZT260 also has a very slight misfire on pickup when cold but on the Autobahn appears ok. It is in the Rover/MG workshops for the time being for other repairs such as the horrible rear window clips leak which allows literally pints of water into the boot wheel well area. I will get back to the forum to report on the cause of the misfire which could well be the coil or wetness around the plugs as already mentioned.

AndyG
18-01-2014, 09:08 AM
.................


WELCOME :D

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colintf
06-02-2014, 01:28 PM
I have followed this very informative thread with interest. Our ZT260 also has a very slight misfire on pickup when cold but on the Autobahn appears ok. It is in the Rover/MG workshops for the time being for other repairs such as the horrible rear window clips leak which allows literally pints of water into the boot wheel well area. I will get back to the forum to report on the cause of the misfire which could well be the coil or wetness around the plugs as already mentioned.

Hi and welcome Peter.
You are in Germany?
:cool:

438brad
27-02-2014, 05:25 PM
Thanks for the info - Battery light sorted now i have to find my OBD reader in the garage (messy) where is the OBD socket hiding on our cars?

There is a third of a tank in it i never let it go down past the last line to risky with our gas guzzlers! I'll fill her up and see on way home later.

I know this is from a while ago, but how did you sort the battery light out, i.e. stop it flickering?

gignwah11
28-02-2014, 12:02 PM
I have bought a new battery and will be fitting today hopefully, as my battery is around 11.5v which is not good. See if that helps solve the problem.