Hello. My 175,000mi '96 has a very rough shaking idle-upon starting, and sputters throughout acceleration. Check engine light blinking steadily so I changed the spark plugs out. Found oil over 5 of them w/ the porcelain covering the metal. Didn't help-same problem still.

Since I have to start out cheap, I will be doing the following:

1) PCV valve
2) Oxygen Sensors
3) ??? Any suggestions?

Thank you all in advnace.

 

i would suggest cap and rotor but if your getting metal shaving on your sparkplugs you got much bigger problems, you may need to do a rebuild. one thing you could do to see how extensive the metal shaving are is change the oil and see if there are any shavings in the oil as well. you may need to replace the rings.

 

sorry nevermind the metal shavings i read it wrong but changing the cap and rotor got rid of the engine light on mine and you may still possibly need to change your rings

 

If you found oil pooled in the spark plug holes, you'll need to replace the valve cover gaskets. The gasket has integral sealing rings that prevent oil from reaching the spark plug holes. Yours have likely failed. Oil surrounds plug, impurities in oil allow some ignition energy to go to ground instead of full energy going to plugs.
I'd suggest changing the gasket, then cleaning your plug wire boots to remove any oil that has clung to them.
PCV Valve, never a bad idea, since they're cheap.
Cap and Rotor replacement would be a good idea as well. you can visually check them for carbon tracks. Hold against light, flashlight may be best, and see if there's any lines, light grey appeared on mine, in a slight zig-zag. If so, replace.

 

Start cheap? OK, let's talk cheap.

1) PCV valve - pull it out, clean it up a bit, shake it, check that it rattles. Now blow in it, it should pass air one way, block it in the other. If it passes, put it back (the right way around). Check the PCV hose condition what you're at it.

2) Oxygen Sensors - no way, not cheap, consider them only after you've done the other stuff. If the CEL is flashing, that's ignition related, not O2 sensor.
Mixture, EVAP loop, faulty O2 sensor(s) and catalytic converter faults put the CEL on SOLID, not blinking on and off as you describe.
Only consider O2 sensor replacement when you have direct evidence (diagnostic scan) to justify replacement.

[I did a write up you might find helpful, use the forum search to find this:

04-13-2009, 11:30 AM
Adam S
Junior Member
I have a 2000 Mazda Protege, 1.8L with 5 speed manual transmission @ 190,000 kms]

Adapt it to your case and perform the operations I desscribed.

I can't fathom what you mean about oil and metal on the plugs. More to the point:
What color was the insulator at the tips of the plugs? Black, tan, or grey? Were they all the same?
If the plugs were wet, was it water, oil, or gas?
What is the color of your exhaust on (a) startup? (b) warmed up running?
What color is the inside of the end of your exhaust pipe?
What are your engine's oil and fuel consumption figures?
(If you have black wet oil-fouled plug electrodes, and are blowing blue exhaust smoke, and have high oil consumption without oil leak, you have to consider an engine rebuild or swap; a compression check will make this clear.)