PontiacBonnevilleClub.com

The worst camera-holding as well.

http://www.colliercomputers.com/video.wmv

Take a look at this clip of my LN3, it definitely makes some extra noise, but I have no idea what it is.

Any ideas?

matt

I watched the entire video. I honestly hear nothing odd.

x2

Is it making any new noises? Can you point out a time that you can hear it in the video?

Sounds like a regular 'ol 3800 to me.

i hear an irregular hissing sound, kind of like a vaccum leak but the idle seems fairly smooth.

During the first start, specifically 00:15-00:17. Maybe its more obvious in person but it is much worse in comparison to Don's 91le bonneville. It is also not as strong, all with fewer miles.

matt

Its there. You just gotta hear it in person. Its quite horrible in person actually. And it has no power. It feels like a Geo Metro...even when you're absolutely trying to squeeze every ounce from it.

i hear a sound at start up that sounds like some sort of ticking...

It makes that noise all of the time... You have to hear it in person... Its nuts the amount of noise this engine makes.. And it is completely gutless

* Edit *

Watched the Vid and the camera didn't pick up the noise...

How many miles on it? when was the timing chain last replaced? It sounds like the timing chain. Its definatly not a rod or main bearing.

I heard the car in person... Several times.. Its not the timing chain.. Has to be the Balance shaft and or Valvetrain... And no its not a Rod or a main.. Car also has great oil pressure

My 91 also makes close to the same noise but not as bad as his..

could it be a bad lifter or bent pushrod?

We thought the same thing... But its not one single pushrod/lifter... I'll just about bet my money on the balance shaft.. I have the same problem with my 91... Not on the same scale as his... I will most likely rebuild the 95 L27 for it once I get it back on the road.. Mine is getting worse over time.. Matts is 2 x's as bad.. Not sure what he is going to do.. He has driven it a long time the way it is with no issues at all..

I'm not sure if the L27 is set up in a similar way to the L36...I think you may only have one knock sensor. Anyway, if you have a tick that doesn't go away and the car is very sluggish, I wonder if it could be false KR. My '95 had it, and it was awful. If you can get a scan tool on it, it is easy to see. Without a scan tool, you can unplug the knock sensor and see if things improve. If the programming is similar to my '95, with the sensor unplugged, the PCM defaults to a spark setting that is retarded 10 degrees. If the KR is bad enough, this can actually be an improvement! It was with my car. I was seeing spark retard above 15 degrees. Talk about sluggish.

Not to be the harbinger of doom... but if I recall correctly, you were driving that car around for months on five cylinders due to a loose sparkplug on #6 (or was it #4). After replacing that plug during SEBF, you felt that the car was running better. Is it back down to that level again?

My thinking is that the motor is fubar. That time spent driving on a dead cylinder may have ruined the rings and bore on that cylinder (raw gas washing the oil off the walls and accelerating the wear.) I'd suggest doing a compression test on the motor at this point to see if it is developing even compression on all six cylinders.

Good thoughts Curt..

I have driven that Buick a few times and for a 3800 its gutless... My wrecked 91 LE pulls a lot harder than his 90 Buick... we have the same gear ratio too.. Something is wrong with Matts car for sure..

Curt, I think that was me that was pushing the placebo that it felt better, not sure Matt really agreed all that much. There was a slight difference when the ECMs were swapped, but that could be just a coincidence. It was indeed loose, definitely some compression loss...yet, its hard to say it was really causing any issues...

When we put the scanner on it and drove it, and I believe this was before the spark plug incident, as well as the ECM swap, it showed no misfires, no KR, full timing advance, no nothing abnormal at all whatsoever. And what makes it even more odd is how well it runs, and how normally drives, but just has no power. It's certainly a unique case for such an engine.

wjcollier07 wrote:When we put the scanner on it and drove it, and I believe this was before the spark plug incident, as well as the ECM swap, it showed no misfires, no KR, full timing advance, no nothing abnormal at all whatsoever. And what makes it even more odd is how well it runs, and how normally drives, but just has no power. It's certainly a unique case for such an engine.

All of that would be true if the motor's bores and rings were shot. Low compression on a cylinder is not always going to cause a misfire, it just burns the fuel-air charge very inefficiently..like going from 80% VE down to 60% VE. You would not see knock and can use all the ignition advance available...the conditions to produce the knock are not there because of the low compression.

At this juncture, I would still do a compression test on the motor just to find out if it is mechanically capable of running normally. It can also be that the entire motor was a dud from the factory. (all the normal tolerances aligning in the worst case combination...not just one component being "bad".)

I think I agree with you Curt... with the way the car runs it can't be anything but low compression.. It idles good and smooth... Drives good... But has less than Ample power even for a 3800... Very possible its the worst of the bunch and is making 165 Hp where the rest of us could be doing 175-180... Matt's motor does feel like a Taurus 3.8 sadly...