Pic of my Spark Plugs

[PotIsYourFriend]

I noticed that my idle would hick up when waiting at a light but when it wasn't in gear would be fine.. So I decided to change my plugs and wires and here's what they looked like after about 2 yrs+.. Any idea what this could be from?

http://www.putfile.com/pic.php?img=3435255

[JTrujillo86]

Yep...you're burning coolant. I'm sure you know this because you're a frequent poster, but check the intake manifold gasket. Since the plugs look like that, I would also change out the oxygen sensor as those can get caked in that white stuff too. If you've been experiencing poor mileage, changing the plugs and oxygen sensors might help, expecially since they have burnt coolant on them. Before switching out the sensors, get the issue of burning coolant fixed that way the new sensors don't get contaminated.

Have you been seeing white smoke out the tail pipe on hard accelerations?

- Jeremy

[PotIsYourFriend]

Originally Posted by JTrujillo86

Yep...you're burning coolant. I'm sure you know this because you're a frequent poster, but check the intake manifold gasket. Since the plugs look like that, I would also change out the oxygen sensor as those can get caked in that white stuff too. If you've been experiencing poor mileage, changing the plugs and oxygen sensors might help, expecially since they have burnt coolant on them. Before switching out the sensors, get the issue of burning coolant fixed that way the new sensors don't get contaminated.

Have you been seeing white smoke out the tail pipe on hard accelerations?

- Jeremy

That's what I thought but I haven't added coolant in over 2 yrs.. Of course I haven't checked it about that time either.. I'm over 140k with the same engine and just plain to do the usual when it needs inspection.. Buy new O2 Sensors, Cat. and reset to clear the erorrs... Then after 30 miles let the SVS and Traction OFF lights come back on....


Still to this day my temp gauge works when it wants to and everytime I turn the car on and put it into drive those lights come on (SVS, Traction OFF).. Oh well, I just hope I can reach to 200k..

Originally Posted by JTrujillo86

Have you been seeing white smoke out the tail pipe on hard accelerations?

- Jeremy

It does smoke bad when I goose it going onto the freeway.. Which I stopped doing because it's embarrassing.. . But it doesn't smoke anyother time..



I'm only going to replace things so my car can get inspected then I'll just repeat next inspection if it makes it that far.. Hell I've been doing it the past 2 yrs.. Sure I could get the intake fixed but knowing my luck the car would crap out 1 week later..

[BNaylor]

What color is the smoke? How is the oil consumption?

What I see reading your spark plugs are ash deposits. Typically that is leaking valve guide seals and/or worn piston rings. In order words you are burning oil.

Also, you think it might be a good idea to check your coolant level more frequently?

[PotIsYourFriend]

Originally Posted by bnaylor

What color is the smoke? How is the oil consumption?

What I see reading your spark plugs are ash deposits. Typically that is leaking valve guide seals and/or worn piston rings. In order words you are burning oil.

Also, you think it might be a good idea to check your coolant level more frequently?

I don't know what color it is because I seen it only a couple times and it was at night.. I do have to add a quart of oil usually every week..

[BNaylor]

Originally Posted by PotIsYourFriend

I don't know what color it is because I seen it only a couple times and it was at night.. I do have to add a quart of oil usually every week..

Just a guess but it is probably a white/blue color. Best thing to do is have a friend follow you in another car during the daytime.

But based on using 1 quart a week I think we can assume it is burning oil. That is way too much. My Alero doesn't have the mileage you have but it uses near 0 every oil change or 3,000 miles.

You might consider running an engine compression test just to verify.

When you first start cold are you getting any noise from the engine like valve tappets or piston slap?

[PotIsYourFriend]

Originally Posted by bnaylor

You might consider running an engine compression test just to verify.

When you first start cold are you getting any noise from the engine like valve tappets or piston slap?

It's the same as when I first bought it.. It's that pinging noise when you first start it but goes away.. But...... Sometimes when it's still cold (engine) and I goose it it sounds like I have BB's in the engine.. I usually let up on the gas when it does this but after the car is warmed up it won't do it..

[BNaylor]

Originally Posted by PotIsYourFriend

It's the same as when I first bought it.. It's that pinging noise when you first start it but goes away.. But...... Sometimes when it's still cold (engine) and I goose it it sounds like I have BB's in the engine.. I usually let up on the gas when it does this but after the car is warmed up it won't do it..

The 3400 is susceptible to piston slap due to GM design. The noise sound should go away after 30 - 60 seconds of engine warmup. The problem with piston slap is the cylinder wears into an oval pattern so the rings do not seal as well. It gets worse when the engine accumulates mileage. I get piston slap when the engine is cold but it disappears after 30 seconds of warmup.

Checkout this tech site for more info on GM piston slap.

Click here

[JTrujillo86]

I thought the deposits on the plugs would be black or resemble dark soot if oil were burning...am I wrong? What color are the plugs if the engine is burning coolant?

- Jeremy

[BNaylor]

Originally Posted by JTrujillo86

I thought the deposits on the plugs would be black or resemble dark soot if oil were burning...am I wrong? What color are the plugs if the engine is burning coolant?

- Jeremy

Although I am an Engineer I am not a Chemistry Pro but that is the way oil looks when subjected to high combustion chamber temperatures. Even bad gas can look that way to include chemical fuel additives.

But I believe we can safely say he is definitely using and burning too much oil. Also, in his case I could see a few of the cylinders look like that with a bad intake gasket but not all 6 of them where it looks consistent with the others.

BTW - I used the NGK spark plug reading guide/chart I have in my garage.

[PotIsYourFriend]

I checked my coolant level and the resevoir was empty (atleast from where the cap goes looking in), I added around 2 to 3 qts of coolant... Is that alot without adding some in about 2 yrs?

Hell I know my parents had a Blazer and they never added or flushed it for 10 yrs..

[PotIsYourFriend]

Originally Posted by bnaylor

Checkout this tech site for more info on GM piston slap.

Click here

So another words is, they cut some corners building the engine but customers can't take them to court?

[xeroinfinity]

Originally Posted by bnaylor

The 3400 is susceptible to piston slap due to GM design. The noise sound should go away after 30 - 60 seconds of engine warmup. The problem with piston slap is the cylinder wears into an oval pattern so the rings do not seal as well. It gets worse when the engine accumulates mileage. I get piston slap when the engine is cold but it disappears after 30 seconds of warmup.

Checkout this tech site for more info on GM piston slap.

Click here

Good write up !

I guess I'm lucky that both my 3.4s are slap free.
well for now any way.

THose plugs do look like oil burn off, pretty bad too.

[BNaylor]

Originally Posted by xeroinfinity

Good write up !

I guess I'm lucky that both my 3.4s are slap free.
well for now any way.

THose plugs do look like oil burn off, pretty bad too.

Hey JC. Probably coolant too.

If I were him I'd get rid of it.

We get a little in our Alero when engine is cold but only for around 30 seconds or so.

[xeroinfinity]

Sorry Bob I did mean oil and coolant, been a long day
If it were just oil it would be black nasty.

My GT has a lifter tick for about the first 1min when cold out .
Tho This is something I need to keep in mind when I add boost to the SE