[NoCalNick]

Good day all,
I did a bit of searching around and seem to think this is either a MAF or TPS issue.
The deal is that upon startup, sometimes, more often when cold, the subie pukes tons of black smoke (fuel over use). Turn the car off, turn it back on again and it may.........or may not be fine. Usually after a few shots at this we're good to go.
Some days it's just fine.
Have poured tons of cleaners down the throttle body in the past, new plugs, wires etc, but if it runs well sometimes, should be none of the replacement parts correct?
In any event, please point a guy in the right direction of "first this, then this" type troubleshooting. I'm counting on experience to save me some hours here.
Additional info, the car "grew up" on the east coast and now resides in northern california. 212K miles, new cats last year to pass smog, manual, 22 or so MPG. Used for towing scrap metal (1000-1300#) net weight (maybe an additional 300# trailer) a couple days a week for 40 miles.
Fresh timing belt etc.

Thanks in advance,

Nick

 

[NoCalNick]

OK, new plugs, full can of carb cleaner down the intake, same issue in the morning....................next???:28:

 

[ntippet]

What is the outside ambient temperature during a cold start.

 

[CSFiend]

Fuel injector sticking open?

CEL on?

 

[cardoc]

^What he said. Any error codes?

How long since the timing belt? Did it start smoking after the belt replacement or before?

Cam or crank sensor needs to be checked. Mainly their plugs and wires. Also, proper orientation of the belt.

MAF sensor tells the ECM how much air is entering the engine. If it is reading high, the computer adds fuel to match the air. As the engine warms up, it is more capable of burning the fuel.

MAP/BARO tells the ECM the pressure on the intake. It calculates fuel trim based on altitude.

More Info.

 

[NoCalNick]

Will check on the error codes, but this has been doing it since I got the car (65K miles - Oct 2010) from the east coast.
Ambient temperature can be as high as 40 when it begins and rarely warmer, but almost every time below that temp. Shut it off, restart and it's gone............... might take two restarts to make it go.
Not sure how to check the sensors.
Also, the cats were replaced last year to pass smog.
I'll be taking the beast apart for a head gasket change this weekend, new clutch and axle boots. Should I check anything whilie I'm up to my eyeballs in Subaru?
Thanks!!