[align=right]edit delete [/align]I need some advice on what could be making my tt run so sluggish in the cold?

I just had some problems with the car stalling out, backfiring, misfiring, and tons of exhaust coming out when i started it cold. it was also running sluggish since its gotten cold out and it was getting about 14 mpg with no check engine light on at all.

I unplugged the maf and it started up fine for about a week then went to hell again. I replaced the engine coolant temp. sensor, plugged the maf back in reset the ecu and it started up better, then the cel came on for low reading on the maf. so i replaced that and it is getting about 22 mpg in the city now but is still running sluggish.

I was thinking maybe a clogged air filter, cat, or bad o2 sensors but i dont know what else i should look for.
any input would be helpfull!!![/align]

 

Change your spark plugs (gapped to .032 for stock, .028 for chip and use stock heat range), air filter, and fuel filter. That all should cost about $45 and take about 2 hours to install. If this doesnt cure it, report back

and if you dont have a boost gauge, BUY ONE!!!

 

i changed the fuel filter this past summer and put new plugs in gapped at 32 thousandths but when the car was misfiring and stalling it fouled out all four plugs. i took them out and cleaned them with a wire brush and some seafoam fuel system cleaner but didnt check the gaps to make sure theyre still at 32. and as far as the air filter im just going to trash the injen cool air i bought cause i live in michigan and it kills it in any snow or rain so im going back to the stock air box since i have a new filter in that. i have a boost guage also and it idles at 20 inHg when warmed about 17 if cold and boosts beetween 8 and 10 psi stock so its normal.

ive heard bosch recommends changing the o2 sensors at 80k to 100k miles do you know if this is true cause im going on 116k but ive checked prices and theyre around 170 apiece so which one usually dies first?

 

If there is a problem with one/both of the o2 sensors, you're guaranteed to throw a CEL.

 

pressure test your intake, that has solved some of the biggest PITA problems for me.