I don't know if you'll make it all the way to burning a valve, but carbon around the plugs can definitely cause problems. I changed plugs on the wife's Audi A4 once and then couldn't get it to start at all. It was one of those oh-crap-what-the-hell-did-I-do moments.
Had it towed to my mechanic who diagnosed no compression: when I pulled the plugs the carbon cracked and lodged on the valve seats so the valves weren't closing fully. The 1.8T is known for carbon buildup issues and with the five-valve design the valves are pretty close to the plug, so I hear this is a fairly common issue on these Audi/VW engines. In any case, he just ended up flushing the carbon out with Seafoam so it was a cheap, easy fix, but definitely scary at the time. I've changed a lot of plugs on the Alfas and have never had a similar problem, but YMMV. I haven't heard the bit about loosening the plugs partially first, so no idea if that will work. Myself, next time I change the plugs on the Audi I plan to do a Seafoam decarboning beforehand! Tom On Jan 30, 2010, at 4:12 PM, alfa-digest wrote: > Date: Sat, 30 Jan 2010 16:12:18 -0800 > From: Shawn Mayer <[email protected]> > Subject: [alfa] Spark plug changes > > Hi all - > I've got a 79 Spider with SPICA here in Portland, OR. I was driving it > very regularly into the first part of winter, but haven't been out in > a while. The last few times I drove it, I was having a really hard > time starting it, and when I last tried a couple of weeks ago, it > wouldn't start. > > I am hoping it's just fouled spark plugs - as I know it was running > rich for a little while before I had the pump adjusted. I picked up > new plugs (Bosch platinum plus 4016 - hope it was a decent choice). > However, I recall reading a suggestion on hear earlier that if the > plugs haven't been out in a while to turn them a half turn and start > the car before swapping plugs so that the carbon formed around could > go out the exhaust. The writer of this post said that otherwise the > bits of carbon flake from changing the plugs could potentially result > in burning a valve. > > Of course, I probably need the new plugs before the car will start - > so, does anyone know how real a concern this is? I've had a burned > valve before, and I want none of that. > > Thanks, > Shawn -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
