Weird Start problems

[nzKAOSnz]

92 BF Subaru Legacy VZ (Jap import into nz) - 2.0L quadcam N/A
K&N Panel filter
2 1/2" back section, catless, snorkless.


Start the car cold - catches, runs up to 1200 odd, then it comes back down before smoothing out. If im not careful, it with die, then take a lot of cranking and pedal pumping (5-10 sec) to fire again. If u start it, then just give it the gas for 1-2 sec, u can take foot off and all good. Any one got any ideas?

Another issue - may be related or not - when cold (like outside overnite) - you start the car, go to take off and it bogs down. Really have to ride the clutch and revs for the first 20m. Or rev and hold at 3000 for 20sec. Then its all sweet. Doesnt do this starting warm.

3rd qn - engine braking down a hill - i afterfire - a few small pops and occasionly a larger one. Is this a worry or nt?

Oil/air/fuel filters have all been done - still does this.
Thanks for your help (in advance)

[Legacy777]

Backfires are usually related to an overfueling issue. Do you have any sort of blow off valve?

The stock bypass valve might be sticking and messing with the amount of air and cause an overfueling problem.

I'd say all these are symptoms, however without doing some more testing, I'm not sure exactly what the actual cause would be.

Possibly a bad coolant temp sensor.

[nzKAOSnz]

N/A - no BOV

Recleaned K&N - backfiring stopped. (So far)

Have to wait for another really cold morning for the other problems.

[americanyouth]

Just throwing a suggestions out:

Clean the MAF sensor? When mine was dirty, I got a rough idle, the car easily stalled out.

As to the afterfire, its perfectly normal, you simply couldn't hear it earlier w/ the stock exhaust.