sorry about the donation but im still waiting for this lady to pay me for my work. I'm helping my friends aunt out. she just recently purchased 2004 Buick Lasabre v6 with 231,000 miles. the owners had told her there was a knock and we told her not to buy the car, but she just had to have it. she brought it to me because the check engine light was on. i plugged up my odb 2 and it popped out po306 (cylinder 6 misfire). it also made this screeching noise, and it sounded lik it was coming from cylinder 6 as well. i checked injectors they were good. i checked the plugs and they were bad. so i replaced all plugs and wires thinking that it's making the screeching noise because cylinder 6 is not firing at all. replaced the plugs and it it still makes the screeching noise. i've never heard a noise like this its not a knock like a bad cam or lifters, its not a tick like bad valves. i think it might be the piston rings are shot and it is scratching against the cylinder. or cylinder 6 is dry and not getting oil in the cylinder maybe, because the rings. i just want to know if you have ever heard a noise like that, and if so know what it is.
Jun 26, 2014 at 10:36 PM
