it usually happens when i first start in the am or after a drive

 

 

it misfires for about 45 seconds and it idles fine

 

now i have already replaced the following:

plugs, wires, coil, ignitor, injectors, fuel pressure regulator, fuel pump

 

im out of options

maybe 02 sensors? howbout knock sensor?

 

just a thought lol

 

-jarrid

o2 and knock wouldnt have a misfire symptom

 

it could run a bit lean or rich but not misfire like it is

 

now how about the AIC?

If those were all quality parts I've seen coolant temp sensors cause this on other (non Subaru) cars.

i was thinking about that CTS...

i was thinking about that CTS...

 

Often a good operator with the fancy Snap-on scanner can check that reading to see if it's out of whack.

 

Don't forget there are 2 coolant sensors, one for the ECU and one for the dash( a spade terminal under #3 intake) it seems.

ok i changed the CTS and still doing it

 

now... can a intake manifold gasket do this?

Yes,but,there would not be enough heat in the engine after only 45 seconds to close an intake leak.Additionally,you mention it also happens after a drive when the engine is presumably warm.

 

I suspect fuel or coolant fouled plugs.

keep in mind that the computer in default mode untill the engine

gets to normal operating temp. It is not unheard of to get bad

Parts that are "new" I recienty bought a new airflow sensor and

it was bad right out of the box... Recheck the conductivity of your

wires.

it happens after I drive, park and let it cool down a bit then when I try I start it misfires for about 20 seconds or so or until I step on the gas reving it up

I'm just going to ask because I didn't see it specifically stated.......

how do you know it is misfiring? Is the CEL/MIL flashing? What cylinder(s) does it say are misfiring?

no cel... it misfires then if pu rev it up for a bit it stops as it goes back down to idle

Maybe it is something other than misfire. I didn't know it was possible for it to misfire repeatedly like that and not throw code(s) P030x.

Maybe it is something other than misfire. I didn't know it was possible for it to misfire repeatedly like that and not throw code(s) P030x.

 

Often is a missfire and no codes it seems to be fuel delivery, timing or valve problem because an electrical issue almost always sets atleast a pending code if not an outright CEL.

I just replaced the intake gaskets lets see what happens I'll keep everyone informed

o2 and knock wouldnt have a misfire symptom

 

it could run a bit lean or rich but not misfire like it is

 

now how about the AIC?

 

They can, but the O2 will not affect running when cold.

Knock sensors typically set codes when they get bad enough to cause misfires.

 

I had a problem with a cold start misfire. It was a bad head gasket. Coolant was weeping into cylinder 4 as the engine cooled down down. When started it might misfire for 5 seconds, 30 seconds, or sometimes not at all.

Check your coolant level.

ok this is the second day after replacing the intake manifold gaskets and still no sgn of misfire when starting cold or warm

doh! it started doing it again today.... im gonna replace the ecu next and see if it gets better.... compression checked in all 4 cyl... im running out of options

Nothing wrong with the ECU.

 

If it is always #4 and not throwing a code it can be an injector leaking.