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Yes, that "8 valve" should have given it away... Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Mon, 7 Mar 2005 09:53:49
In Reply to: Re: Knock, ping or (!) rod knock, Jimmy S., Mon, 7 Mar 2005 08:28:10 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Yup, spring, not hydraulic lifters. You may still have a sticky valve.
The gas smell could be caused by failure to ignite - that could be too much fuel, it could be a stuck valve (I keep coming back to that, don't I?)
Rod knock could occur only as the engine warms up, as the clearances change. Rod knock is pretty loud - very hard to miss. That's why I'm trying to focus in on the sound. Detonation or ping tends to be a quieter, almost rapping sound. Rod knock is a very loud metallic sound, and the stuck valve can sound like a bell being struck. Again, loud.
Here's a question - if you shut the engine down right as it starts to knock, and pull out the spark plugs, what do they look like? How do the plugs look normally? If the cold start valve is the culprit, you'll find all the plugs covered with fuel. If only one injector is sticky, you'll find only one plug covered in fuel.
A turbo engine has very low compression, and at idle and no boost, it would be very, very hard to get the fuel to detonate. Especially if you've got too much fuel - it's hard to get a rich mixture to burn; it keeps the area cool, displaces air, etc.
Check the plugs - they don't lie. And try and isolate if it is a detonation (ping) sound, or a mechanical knock.
posted by 192.249....
, Mon, 7 Mar 2005 06:06:59, Mon, 7 Mar 2005 09:53:49 <-- Viewing This Message
, Sun, 6 Mar 2005 20:50:25
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