Hi guys, I've recently bought my first impreza WRX, and am having some running problems.

I initially noticed for a start that the car is hesitant to boost until upto full temperature. (This may well be normal)

For a couple of days, the car ran okay. Boosting relatively well, although not entirely smoothly. It would pick up from roughly 3000rpm, and pull through to just over 4k, hesitate a little, then continue. My clutch seems to be pretty elderly and smelly at times, so this may well just be the clutch slipping at high torque (clutch will be being swapped out shortly)

When driving today, i noticed that from 3500rpm when boosting, there's a noise, almost like screaming, coming from (very vaguely) the location of the turbo.

After this had happened a couple of times, i got a flashing EML on the dash, that then turned solid. I pulled over and connected to the OBD scanner.

P0302 - Powertrain
Cylinder 2 Misfire detected

since this, whilst running relatively normally, the engine is a little tappety sounding, particularly when lifting off the throttle.

There are a few mods on the car, but I'm not aware that the car has been mapped to suit these.

I've had a good read through the sticky regarding misfires, and will be starting at the top of the list with spark plugs first thing in the morning.

so I guess what I'm asking is...

A) anybody had anything similar happen?

B) are the NGK PFR6B spark plugs a good choice? Or should I pay more for the PFR7B?

Thanks in advance
I've had a read throu the rules, but I apologise if I've done anything wrong


Car is a 2004 Blob wrx

Full Decat
Pipercross panel filter
290LPH fuel pump
96,000 miles

 

Anything from a loose spark plug or bad exhaust gasket to a broken piston or bottom end failure.
Start with the easy and obvious stuff 1st.
Unmapped full decat can kill an engine,might have been detting it's *** off for a while?
With any luck it will be a simple problem.

 

The Y hose could be split on the Turbo to TMIC or even a loose clip if you have touched it, the scream or as mentioned up pipe leak,
if it has been mapped they can add the function to limit boost until a certain temp , so you may have a no issue there, but it wouldnt explain the miss fire on cylinder 2.

 

Thanks for the replies, guys

Interestingly, I changed the horrible BOV to an original recirc valve, and the gasket for this connection was PRETTTYY bad. Could this cause similar boost issues? (this was next on my list until these problems started - then a proper map)

 

Yeah, good place to start.

 

And stay OFF BOOST until it's at least had the map checked.

 

So
sparks replaced, and all connections cleaned up

​​​​​​no real noticeable difference in anything

the ticking noise is now what I would refer to as a knock, and isn't terribly loud, but it certainly wasn't there last week...

it's kinda there on tickler, and most prominent around 2000rpm
aaaaaany ideas?
still no fault codes appearing beyond the misfire one, and that hasn't actually appeared yet

 

if the knock is there from 2500 rpm to around 3300 rpm then your bottom end is gone, driving a unmapped car can cause this.

 

As JDM Stig says,doesn't sound good.
I would drop the oil asap,filter it through a cloth and see if there are any metal bits in there.

 

JDMStig - knock is exactly in that rev range... fantaaaaaastic!

Yeah, unfortunately the decatting etc was done long before I bought the car last month.
Why don't people look after nice things? :'(

 

If bottom end HAS gone, how would I go about confirming this is the case? Would the best bet be to take it to a scooby specialist to confirm?

 

If the bottom end HAS indeed gone, what would be the best way of figuring out if this is the case? Driving it to a scooby specialist?

 

Although your description does sound like the start of bottom end failure don't right it off just yet,there are other noises that can sound like rod knock/bearing failure.
Did you check the up&down pipes and manifold for signs of blowing?
A loose inlet manifold or bad gasket can also sound similar,as can a loose spark plug but you said you've replaced them so can rule that out.
Another similar noise can be the valve clearance out of tolerance,see if you can identify where in the engine the noise is coming from.

 

Sorry Dude

 

Because they know better than others?

I've lost count of the times I've been told, on here, "You are only saying that because you are an oldie and don't want us to have fun. Take no notice of the oldies...do it, mate. It worked fine on my RS Turbo....etc etc etc"

And other such ****e.

 

It's going in to my friendly local engine technician tonight
most likely looking at a rebuild...

I'll keep posted on how it goes
​​​​​

 

If rebuild is needed give me a shout - might have some bits that could help you out.

Fingers crossed you won't need though!

 

"local, friendly"???????

nooooooooooooooooooooooooooooooooooooooooooooooooo o.

Take it/get it to a specialist.

 

Whilst not technically a scooby specialist, these guys are super advanced in their work. They build racing engines for subarus, skylines etc. I'm quite confident in their ability to rebuild one of these

"local and friendly" were on the sarcastic side tbh. Everyone's friendly when it's time to hand over a couple of grand