Silvia Club of NSW

As stated above, I just got myself a Silvia! Its a black 1990 1.8 turbo automatic . Actually I don't mind the auto that much, its a smooth ride and the 3 modes (power, normal and hold) are awesome. Pretty much stock at the moment though but i hope to get some pics up soon. Oh and as for the questions:

1. It seems to be leaking oil (patches found under car). Automatically i just assumed that since it was the CA18DET that the screws had loosened or something? After some browsing through forums i got to thinking that maybe it was the turbo leaking? Can anyone give me some advice or something specific i should look for to determine the cause?

2. Engine shakes quite abit when idling, engine mounts? just wondering if this was normal?

And lastly, about 10minutes after I turn the engine off, i hear this knocking sound, one loud knock. I think its coming from my car because I've heard it a couple times, is this what they call detonation or pinging?

Thanks in advance guys

Egads

I am not really much of an expert on Silvia's as others here but here is some advice on your concerns.

Pinging or predetonation is when the fuel mixture explodes before it should. It happened once to me. The water hose that goes to the turbo burst and the car basically lost all the water and overheated. I heard a pinging sound and stopped straight away. Luckily no engine damage due to me stopping straight away. In that case the pinging was caused by the engine being so hot the mixture was exploding before the spark from the spark plug. I think pinging is normally caused by being out of tune rather than the engine being much to hot. As pinging happens when the engine is running the noice you hear after ten minutes of the car being turned off is definitely not pinging.

The Turbo runs at very high speeds and gets very hot. It is important to used a good quality oil ( I use Mobil 1 5-50 as it is quite thin and gets to the turbo easily) and change it at least every 5,000km to ensure the turbo does not get to hot or worn due to dirty oil. The tube that takes oil to the turbo is quite small and can get blocked with dirty oil. I fitted a turbo timer to allow the turbo to cool down. I hope the noise you hear is not your turbo contracting after getting very hot and not being cooled down properly. I would recommend a turbo timer as it makes it safer for the turbo.

My engine is quite smooth at idle. It runs at 1,500 for about three seconds and then drops to just over 500. It does not sound anything like a WRX.

My car is a 1.8 turbo convertible that was an auto and now has a manual gearbox. I had never owned an auto before and thought the Silvia was much better than other autos I had driven but Imuch prefer the car as a manual. I live in Canberra and hardly ever drive in traffic as I ride my pushbike to work and only drive the car on weekends so I really like the manual but the car does not like idleing along in first gear and is not as smooth as before. The manual feels a lot more powerful.

I hope that is of some help to you.

Chris

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Convertibles Rule

1. raise the car and scan underneath for oil patches. especially around any gaskets or bolts.

2. could be your afm. it may be dirty. happened to my s14a.

3. pop the bonnet and get someone else to turn the engine off while you listen to the turbo and the engine to see which one is making the noise.

Thanks for the replies guys! I'm right onto it! Well not right now, I mean its 2 in the morning! I think I need to lie down.

fuel should NEVER explode =) its called a controlled burn, the fuel burns at a given rate increase pressure and pushing the piston down. explosions = lots of pressure and things go bang.

detonation or 'pinging' is when fuel burns too fast, or pre-ignites due to pressure or heat in the combustion chamber, thus creating more pressure really fast =) and exploding fuel.. rings, head gaskets, bearings and pistons dont like this too much, it tends to blow things up, crack things etc..