I have a 1996 Mazda 626, 5 speed, 4 cylinder engine. I have changed the spark plugs/wires. No leaks. Oil and antifreeze both clean. It just lost power and spudders and blows out blue smoke. Took it to Autozone, they said the code said. Cylinder 2 misfire and another one that said multiple misfire. The engine light has been on for a while not but recently it started flashing. Anyone know what this could be?

Stieber; You'll need to pull #2 spark plug and take a look. Check the plug itself for a crack in the porcelain and recheck the gap. If the plug is fouled with oil, which sounds like maybe the case, then a compression test is in order.
Loren
SW Washington

I pulled the spark plug, they are pretty burnt, it is a old car lol, there is no oil on them. But I just changed them about a month ago. Should I get some new ones and try that?

Stieber; Are they 'black and sooty'? You can hold one of the plugs and light a match to 'burn' some of the deposit you see and take a smell. Does it smell like oil or gas? I'd pull all four plugs if you haven't already and compare them to each other. Do they all look the same? Gaps correct? The smoke out of the exhaust concerns me. If it's blue, that means the engine is burning oil which should show up on the plugs. If it's white or gray, may be burning coolant and the plug (#2) would look very clean. If the exhaust is black, would mean that it's running too rich.
I think that at this point, you should do a compression test on all four cylinders while you've got the plugs out. Post the readings when done.
Loren
SW Washington

They look as if they are gray, but on the white part a couple are burnt, but no oil on the gap area. I had a car in the past with a blown head gasket and this car is not giving symptoms of it. No blowing out of the radiator reservoir or gas smell in there and no water loss.


(This post was edited by stieber73 on Jul 11, 2009, 6:34 AM)

Stieber; The plug color sounds pretty normal. I suppose you could replace them if you want, but doesn't sound that you need to. Your decision. This is a belt driven engine. Do the compression test. If it checks out okay, then we may want to check timing marks which will require removing the upper timing belt cover. But, that doesn't explain the smoke......aaarrrggghhh.
Loren
SW Washington

I put some oil in yesterday and this is when the smoking thing started.

Stieber; Just for grins, and I doubt that this is the problem, carefully spray a bit of carb cleaner around the EGR valve with the engine idling. Depending on which runner of the intake manifold it's mounted, could be causing a vacuum leak to #2. If the engine speed picks up when you do this, remove the valve and check for a piece of carbon holding the pintle open.
Loren
SW Washington

Stieber; Check the oil level and be sure it's not overfull...Did the loss of power thing start at the same time, too?
Loren
SW Washington

yes it did

stieber73
ls there any chance the dipstick is wrong? Only real way to know is to change the oil, put in known capacity minus one qt and make a mark there. Then add the full capacity and mark it there too. Not common to this car but it was with some. I used a punch to mark the low level and the full mark on OE wrong dipsticks and ground off any info that would be misleading.

Just my 2 cents. You are in good hands with Loren!

T
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Tom Greenleaf - MetroWest, Boston
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