PDA

View Full Version : White spark plugs


armthelaser
03-06-2005, 06:32 PM
I have a plymouth laser awd Turbo and i was changing the spark plugs and the tips of them were all white. This means that it is running lean right, I am only running my boost at 10psi with a stock turbo. Why would I be running lean? Would it be that the fuel filter needs to be replaced or is there something else I can try too.

JET
03-06-2005, 06:43 PM
The plug ends should be a light tan if everything is correct. White tips could possibly be coolant too. Is the MAS hacked at all?

TheBlizzard
03-06-2005, 06:50 PM
Fuel pump could be on its way out too. If they are all the same I would rule out injectors. Like Jet said possibly coolant. But I would say its running lean, but from what could be a number of things.

CRAIG

TGPilot
03-06-2005, 09:34 PM
Are the deposits crusty white or smooth white?

Crusty chunky looking deposits are normally from fuel additives.

If the electrode is covered in a real smooth (not glossy) white residue then most likely you are getting coolant in your cumbustion chamber. It is hard to get coolant in all cylinders though. Maybe a tan colored or off white is what you are seeing. If it is off white towards tan you are running lean.

Also look up in the base of the plug. If you are darker colored up there and light colored down on the electrode then you are running rich at heavy load and clean to lean during cruise.

There is a science to reading plugs and I am not an expert by any means. You may want to do a google search on plug reading to properly read your plugs. Just a suggestion.

armthelaser
03-07-2005, 08:36 AM
I changed the plugs because I was getting knock. I logged again and it was at 0 knock again so it fixed that, someone else said coolant but they said probably not in all cylinders. What should I do to test for coolant, pressure test?
Yes my MAS is hacked why does that matter?

JET
03-07-2005, 08:58 AM
You will run leaner with a hacked MAS and no compensation for fuel.

TGPilot
03-07-2005, 09:43 AM
You can do a pressure test on your cooling system and/or compression test on your cylinders.

Cooling system requires the hand-held pump connected where the twist off pressure cap is.

For cylinders you need a pressure gauage on a long hose with the appropriate plug threads to thread it on. Crank the engine with no spark to any of the cylinders (you don't want to start it) for 3 or 4 seconds. Let it sit for 1/2 hour and see how much pressure you lose.

DSMPARTSGURU
03-07-2005, 09:47 AM
I would definetly pressure check the coolant system...if anything it is a easy test and will make sure that isnt your porblem.

john
03-11-2005, 10:25 AM
You could do a leakdown test to see if the HG is leaking. I would guess that you have some boost leaks or are running a bit lean. As Jet said, a hacked Mas could contribute to it a bit also. I would do a boost leak test first as you should do one anyhow. Then if the car runs fine without an ass load of knock, leave it. I have pulled white plugs out of my car several times and not thought twice about them as the car was running fine. The car is probly just out of tune.