Mk3 Cavalier Owners Club | Vauxhall Cavalier Dot Com

Help! Our Bert has a slight problem on start up juddering low revs, smelly exhaust & when I put my foot on gas it kangaroos but the thing is its not all the time. Any ideas thanks

Strange that it doesn't happen all the time.
What engine is it? Is it the spi c18nz 1.8?

It's a 1.6, after cars been running about 5 mins or so it's fine that's why I'm scratching my head lol it's just strange

Is that the e-drive 1.6 or the regular one?

Have you checked the distributor and HT leads recently?

I have had similar symptoms on my 1.6 after it had been stored and not used for a long period of time. It cleared itself after a good long run though.

It's just a normal 1.6 injection, got some more oil n filter so going to change that & change rocker gasket again cos that's started leaking again. While I was at it I was going to check plugs, clean distributor. Do you think fuel filter could cause this problem? Thanks

A bad fuel filter could similar symptoms but I can't see why it would stop after a few minuets of driving.

Ok thanks for replying to me. I'll try doing what I've said in going to do & fingers crossed it works lol. Got to be sorted mot time soon..... Ooh another thing I've had front pipe changed recently and they put the old lamber sensor back in as they said it was ok you don't think they could have disturbed any wires or anything

I have the X16SZ in my car, had similar issues, although once the car was warmed up - smelly exhaust, poor idle, juddering under load and not starting up unless I gave it >50% throttle. Turned out to be the coolant temperature sensor.

Just to confirm, that it is the coolant temperature sensor with the square two pin connector for the engine ecu.

Not the one on the front of the thermostat housing - with a single female spade connector. That is for the temperature gauge on the dash.

These sensors can go wonky in two ways.
Normally reading too cold, so the engines revs quickly for a few seconds immediately upon starting before settling again.

Otherwise, like yours, they can tell the engine that it is warm when it isn't resulting in gut-less revs or stuttering like fuel starvation.
(Fuel enrichment not being triggered).

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I can see where the ignition system reference could be an issue too.

I have had a mis-fire on a first start of the day engine, when the leads are on their way out. (Breaking down), or there may be some corrosion on the ends of the leads.
Especially the lead to the coil.

Normally giving everything a good check over and making sure that they are clean, dry and securely fitted will cure most issues.

Think you could be right with those wires because now I come to think when I first had it done the temp gauge in car didn't move at all until I wiggled the wire with just the spade on it then it started to move again, so I'll check them others that lamber plugs into... Thank you

Hi Suzi,

The sender with the spade on, should have no effect on the running of the engine.
It is only for the temperature gauge.

The one that affects the running is one at the rear of the engine, near to the timing belt cover / alternator.
A rectangular sensor with a two pin plug going to it.

If waggling wires helped, check all your brown earth wires.
And same for all wires on the loom for engine ignition system.

And a super-long shot - is the interior of the car dry near to your bonnet release handle.
I mention this, because some "older" cars can suffer moisture ingress around the window frame due to corrosion of the metal etc.
In unlucky cases, moisture / water can get down behind the kick panel in the driver's footwell.
Behind here is the engine ECU - as you can understand when this gets damp, all sorts of running issues can happen.

But - I would concentrate more in the engine bay, as this is where most "extreme" conditions occur.
Cold and condensation when the engine is stood in cool or damp weather, to hot and dry when the engine is stuck in standing traffic or on hot summer days etc.

As with all stuff car related - make sure that everything is: -
1 - clean (shiny metal not green or orange corrosion).
2 - Dry (moisture can cause all sorts of issues).
And
3 - securely attached / fitted ( loose or damaged wires and connectors are a major cause of intermittent faults).

I apologise if I sound obvious or simplistic.
It is sometimes easy to over-look the obvious simple things.

Just re-read your comment about the exhaust.

It is likely that they have disturbed some of the wiring to replace the front down pipe.

However I cannot see why they would have to.
I thought the lambda was in the exhaust manifold on the 1.6 and 1.8 central injections..
As such, when the engine is cold, the lambda is "ignored".
So again - a possible hint that the coolant temperature sensor has gone belly up - engine ECU thinks that the engine is fully warmed up when it isn't. Catalyst smell on a cold engine, or fuel enrichment not being engaged.

Firstly - Just trace all the wiring around the engine bay, and make sure that it is all securely connected up, clean and dry. (I am sounding like a cracked record here....ha ha).
These checks are free and simple to do so no harm in doing them first.

Lamber is fitted to front down pipe off manifold, the sensor with spade in was green till I cleaned it up. I'll definitely check all other connections still give em a clean tho . No leaking inside the rubber around window is fine, had to have a new screen other year & all metal work around window was fine no rust what do ever... again thanks for all your help

Ah okay.
I stand corrected.

So the lambda is in the top of the down pipe just behind the engine.

Same as the 2 litre 8 valve set up then...

In that case, check that it is fully screwed in, and that the wiring is routed away from any hot or moving parts..

It's fine when I ordered new cat last yr had to get it for 2 litre & same with front pipe tried telling me car had been messed about with but it's been in family since around 98. It's the concept one I've got just thought that with it being one a last ones off production line that the fitted what parts the got left lol thanks for your time

Just abit of an update, I've done service cleaned all leads cleaned most connections I can see, not got round to temp sensor yet but now when I start car up its totally over fuelling it stinks white smoke coming out of exhaust, plugs showed over fuelling too. It's got worse on start up proper kangarooing when I drive until it gets warm could this still be this temp sensor?? Thanks

I would hope that the white smoke is purely due to ambient condensation from the cooler nights.

The coolant level is fine isn't it.
(A drop in coolant level could infer a deffective head gasket - which could cause a judder if coolant is getting into one of the combustion chambers).

Being positive though....
Over fuelling.

Coolant temp sensor should still be considered as your best culpret.

Is it over fueling / rich - black sooty plugs?

Or fuel leak - Strong fuel smell.?

The plugs were black when I've just changed them, you can slightly smell fuel, coolent level is to maximum not using more than normal. When temp reaches 90 it runs fine no juddering or spluttering, white smoke seems to have gone now too

Oh the fuel smell seems to come from the exhaust

I would recommend changing the O2 sensor too then.
That should help with the emissions.

Here is the right part:

http://www.ebay.co.uk/itm/LS50311-Bosch ... SwzJ5XUYIy

Thanks

Just a thought I've not long since had front pipe fitted when they took lambs sensor out they said it looks ok, should the have disconnected battery?

No need to disconnect the battery to swap the lambda / oxy sensor.

On a Cavalier, you can do most jobs with the battery still connected
Assuming that the ignition is off.

The obvious exception is any air bags.
It is always recommended that the battery is dsconnected before disturbing any air bags.
Although I have known people to fit or remove airbags with the battery connected.