Hey guys, so on my 94 SS I am about to order new wires. Already replaced the plugs which did not look good, and it did not really make a dramatic difference. I am still noticing at idle it likes to flucuate sometimes like rev up and down a TINY bit almost like a slight misfire. The wires definitely don't look to be OEM. I looked really hard and do not see anything wrong with the vacuum hoses. I am thinking ill just order NGK's locally for $40 versus OEM online $35+ shipping to canada and conversion i am over $60+. Is it true NGK's are OEM basically?

 

History on the 94 SS. Has 192,000km, replaced, plugs, pcv valve, seafoamed through the IAC and a vacuum hose, injection cleaner in the tank, air filter, cleaned MAF sensor I THINK and replace knock sensor. Other then that the car is extremely smooth. THe slight studder at idle in P or N just bothers me a bit that's all.

 

Another thing I forgot to mention when I accel from under the hood via the throttle body, I think I hear the boost solenoid make a click noise. ONLY when I tap the throttle just makes a single click every time.

Before you replace them, lets stop.

 

 

Spray the engine with a fine mist of water while its running. Look for sparklies and also listen for RPM changes. One means bad wires, the other means a vacume leak.

 

When was the last time you cleaned the IAC valve?

 

OE wires have a high content of silicon, so they last longer.

 

 

nipper

If it was the wires most likely you'd have a Check Engine light with a cylinder misfire code.

 

Probably not the wires, unless the CEL is on.

 

If it's most noticeable at idle I'd start with what Nipper said - clean the IAC. Very often they get dirty and cause idle problems, very common issue. And it doesn't cost anything except a can of cleaner of some sort.

 

I'd replace the PCV valve too.

 

OEM is best. I've seen brand new after market wires cause issues right out of the box. NGK's seem good, but there's no definitive info on whether they are indeed identical or not to OEM Subaru.

I dont think there is a misfire. It is just fluctuation in the engine speed. I haven't seen boxers which had a super spot on idle. As Nipper said spray some water if idle drops and increases quick than the ecu is responding to some loss in energy send to the spark plugs.

Maybe also clean and/or test the PCV valve with the thumb for clicking noise.

Might also want to clean the throttle plate/body...I have seen similar problems result from a carboned up butterfly....

History on the 94 SS. Has 192,000km, replaced, plugs, pcv valve, seafoamed through the IAC and a vacuum hose, injection cleaner in the tank, air filter, cleaned MAF sensor I THINK and replace knock

 

Maybe another iac treatment? is the pcv one of those "dealer only" items?

Dealer sold me NGK wires and they perform flawlessly (3years service)

as i mentioned already cleaned the IAC, and replaced the PCV with a OEM one. It is not really a misfire it is just the rpms flucuating really.

 

I definitely need to get around to cleaning out the throttle body. Maybe tomorrow if it is still warm.