Question for you 3100 guys

[19Cutlass94]

What do your plugs look like? Since I can remember, mine have always had oilash on them. And recently everytime I would start the car, and when it would be idling ( park, drive, doesnt matter ) you could feel a miss in the engine. I took all the plugs out today and once again, it was the #1 cylinder that I was dropping. There was so much oilash on it that it was just jumping. All the other plugs had some, but nothing compared to the #1 cylinder. But Im not loosing any oil. In fact I havent put a drop in it since my last oil change, about 2,000miles ago. Im thinking its probably the valve seals that are the problem, but does any other 3100 owner have this problem?

[Crazy K]

did you put the plugs in new?

how many miles have you gone on them?

 

are they the regular acdelcos or somthing else?

 

p.s. it was nice to meet you!

[19Cutlass94]

The plugs were put in brand spanking new. Ac Delco copper plugs - R44ltsm6. Ive gone about a whopping 8,000miles on them

 

 

p.s. was good to meet you as well!

[Crazy K]

damn. thats a real short life. that would be two months driving for me.

 

 

what type of oil are you using?

 

have you made regular oil chages?

 

how long since last oil change?

 

did you recently change the type of oil you were using?

 

vehicle mileage?

[19Cutlass94]

Im using Valvoline max life synthetic. Of course Im making regular oil changes. Most of the time its not even 3,000 miles between them. Its been maybe 1,500 since my last oil change and Ive used the same oil since weve had the car. And shes got 98,199 miles on the clock.

[ToroToro]

Mine were like that too. But of course in all the miles I drove that car, one gasket or another was bad for what thats worth.

[97loudcut]

i use delco plats

[fastbird232]

i used delco plats

 

 

[Crazy K]

I was thinking that it could be leak down especially if the oil was too thin... that High mileage stuff could come in handy, it should help make the seals swell a bit... or not...

 

I wonder... have you put new wires on? might be excess resistance on one wire not allowing it to fire all the time. also check the coils, as they occasionally corrode where the wire attaches. and make sure you have dielectric tune-up grease on all the tips.

 

I should ask for pics.... because it is hard to diagnose what can't be seen. got a pic of your spark plugs? maybe it seems worse than it really is?

 

 

[Brian P]

how is your rear valve cover gasket? Maybe it's just getting soaked with oil on the outside, and when you pull it out, it all gets wet. The valve seals RARELY go on these engines and it's impossible for them to lift off the guide.

[19Cutlass94]

Wires are basically brand new. Coils have great spark, and are not corroded. Valve cover gaskets are only a couple months old. We changed all the gaskets on it when we did the LIM. Everything is dry and theres no oil leaks.

 

But the thing is as well, when you take a flashlight and look through the spark plug hole, you can see this on the top of the pistons as well. Its that same white oil ash. I mean I know my car is running a tad lean, but when my dad hooked up the scanner to it, it was in the 'range' that it should be. But it would be hard to get a picture because I cleaned all the plugs.

[Brian P]

OH!! Oil-ash! I thought you were just misspelling oilish...lol. Kay that can change a few things.

[19Cutlass94]

haha, Indeed it does!

[Crazy K]

I'm at a loss.

 

Guess you'll have to get used to cleaning the plug(s) ever other oil change or something. It's not all that bad or terribly difficult if you are used to it.

 

It would not be cost effective to repair the problem any other way. tough luck. a buddy of mine had a caprice that had it's plugs foul about once ever two weeks by comparison. Yours is not that bad, at least.

 

p.s. Wait a minute, duh! I was think of a leaky valve stem seal!

 

Check both of the plastic lines that hook from the valve covers to the intake tube and upper intake manifold. see if they are drenching the intake with oil. maybe it is due to a bad PCV valve. This seems pretty normal for the 3100 motors unfortunately.

[19Cutlass94]

The PCV valve is fine, and all the lines are dry. I thought it might be a valve seal, but I guess it seems like Im the only person here with this problem. And I tell ya it really sucks. Its deffinatly not cost effective to even attempt to fix it. Just sucks how so much oilash builds up and I keep dropping cylinders because of it. Next time I check the plugs, Ill post some pictures. But I mean Ive got oilash on the plugs, pistons, probably the valves as well, and God knows what the cylinder walls look like.

 

I just cant believe Im the only person that has this problem... Well I guess its good for everyone else, but still....

[Brian P]

this is definetly the #1 cylinder and not #5, right? Have you checked compression just for curiosity sake?

[19Cutlass94]

Definatly the #1 cylinder. The #1 cylinder is alot worse than the rest, even though this is a problem with all the cylinders. Nope. Havent done a compression test. I duno if I have the things needed to...

[Brian P]

As mentioned, do you see any oil pooling up in the upper plenum? particularly near the TB?

[Brian P]

You just need a compression gage w/ hose, might run you around $30. I would run a top engine cleaner thru the engine if it's never been done. The GM cleaner seems pretty good, the liquid not the spray. I see you mentioned it needing LIM gaskets recently so I don't know to what extent the engine ingested coolant, this might have affected the sealing of the rings abd valve seals (not as likely). Also, mileage and age dictate if the oxygen sensor was never replaced, go ahead and pick up a new one for the engine. Or at least inspect the one in there if it's caked up. A scan tool would be nice to check what the ECM is reading off the O2 among other things. I know #1 is the worst but if they're all doing it even a little, that's not normal. I've pulled plugs out of my old 3100 with 30k on them and looked close to new.

 

http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqread2.asp

 

http://www.nightrider.com/biketech/spkplghnbook.htm#We

 

[19Cutlass94]

When they are found on both sides of the spark plug, it is often considered to be a problem sealing at the piston rings.

 

YAY!

 

 

As mentioned, do you see any oil pooling up in the upper plenum? particularly near the TB?

 

Gimme like 20 minutes and I can tell you. But I can say that before we changed the gaskets, there was ALOT of oil in the plenum, especially by the TB, but it seemed like the whole plenum was covered with oil. And about coolant, the engine saw maybe an ounce of coolant. We got to the LIM gasket just as it started to crack, so it was very small.

 

Last time we had a problem with it, my dad hooked up his scan tool, went through everything the car was doing, checked over everything and the only thing he saw was that the car was running a little on the lean side. He said it wasnt enough to worry about though... And I do trust him. After all hes been a tech for 40+ years. And as far as I know, its still the original o2 sensor.

[SigEpCutlass]

Even with my leaky plastic valve cover & gasket (hopefully will have time to fix this weekend), I still haven't had that problem Jay.

[Brian P]

Even with my leaky plastic valve cover & gasket (hopefully will have time to fix this weekend), I still haven't had that problem Jay.

 

yeah, I thought he said they were oily, so I suggested that. But that's not the case.

[19Cutlass94]

yeah its not.... I think its just something more serious. And honestly, probably not worth the time or money to fix it.

 

 

EDIT: Yesturday I was driving down the road, and just punched it. I saw some blue smoke coming out the tailpipe ( either that or I spun the tires, but lets be serious here ). Doesnt do this at idle so I think its only a matter of time before the ring(s) let go...

[Brian P]

well doing a compression test can give you a better idea if the rings are going. If it is so, on it's last legs, using thicker oil may help a limited amount, or even an oil additive for just that. You'd have nothing to lose at that point anyway, may as well prolong it some.

[SigEpCutlass]

Did you check the compression yet Jay? How did it turn out?