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Anubis

Noise From Engine When Under Stress

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Hi All,

I have a 98 harrier which has done 70k. I noticed one morning, that there was a lot of oily smoke for a few minutes then it disappeared. I have not seen this since on start up. However, I have noticed that when the car has been running for a while, when I am pulling away or driving up hill, there seems to be rattling/tapping coming from the engine. However, when on a straight or at speed this noise is not apparent. Can any one tell me if this sounds like the valves/tappets.

The noise is not there in the morning or when you pull away, only after the engine gets hot.

Any help will be appreciated, as I am if it is valve replacing then I have been told I need to take it to a Toyota garage and they will change all 24 valves , which if my astra GTE is anything to go by many years ago, then I am looking at a large bill.

Any help would be much appreciated.

Thanks

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Symptoms are of "pinking" or pre-ignition, could be dodgy anti-knock sensors allowing the ignition to run too advanced.

Oily smoke on start up is probably worn valve stem oil seals.

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Symptoms are of "pinking" or pre-ignition, could be dodgy anti-knock sensors allowing the ignition to run too advanced.

Oily smoke on start up is probably worn valve stem oil seals.

Thanks for the fast response. The performance does not seem to be effected. It sounds like tapping noises when driving up a hill, or when the car is under stress. The oily smoke has not been seen since. I thought that valves/tappets make noise at start up, not later on ?

Thanks,

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"Pinking" under load is caused by ignition timing (sparking too early) and not valves :winky:

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"Pinking" under load is caused by ignition timing (sparking too early) and not valves :winky:

Well I really hope this is correct. I wonder if it has something to do with the Tesco petrol comtamination issue. Thinking back, the car did start to fluctuate on revs at standstill about a few days after buying petrol back in Feb?.

We will see what the Toyota person says tomorrow.

Many Thanks again for the promt reply,

A.

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The conditions when it happens and the noise "rattling" under load are classic of "pinking" (sometimes called pre-ignition and also knocking) caused by too much ignition advance or too low an octane fuel.

I either case the ECU should retard the ignition when the "anti-knock" sensors detect it happening.

AFAIK the ECU tries to run the max ignition advance it can and uses the "anti-knock" sensors to do that, hence the faulty "knock sensor" theory :D

Let me know what the "techie" finds.

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The conditions when it happens and the noise "rattling" under load are classic of "pinking" (sometimes called pre-ignition and also knocking) caused by too much ignition advance or too low an octane fuel.

I either case the ECU should retard the ignition when the "anti-knock" sensors detect it happening.

AFAIK the ECU tries to run the max ignition advance it can and uses the "anti-knock" sensors to do that, hence the faulty "knock sensor" theory :D

Let me know what the "techie" finds.

Just spoken to a techie and they have stated that it is valve stem oil seals and it will take 18 hours at a cost of £2092. Can work be done at a non Toyota garage?

Thanks for any response

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I can't see how valve stem seals would cause your symptoms (other than the smoke you mentioned earlier). I would get a second opinion. Make sure you don't mention the smoke when getting that opinion, just find out what is causing the pinking. The other place may be trying to cure the smoking?

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