Rough start up when cold and cel comes on

[tank1707]

I bought my 2003 6i with 68500 and had a misfire problem that occurred only on first start of the day after its been sitting during a cold night, had fuel injectors serviced changed spark plugs and got new ignition coil the problem went away for awhile and the weather warmed so it was starting fine.
The other morning I went to start it and it turned over with a little bit of struggle almost like it was stuck and gave a clicking type noise with some vibration after that it started perfectly the rest of the day but the cel light stayed on. This morning it had soild vibration and some weird noises while trying to start. I'm new to all this so any pointers or advice on how to fix this besides having an auto shop read the code as a misfire and telling me they need to-do an in depth inspection for hundreds of dollars ??

Any help would be great! I love my 6i and don't want to see it slowly start going down!

[tank1707]

The car now has 75500 on it and runs solid but its only start up problems.

[xkreedx]

Go to Autozone or your local parts store and get the code and report back. Sounds like your MAF is shitting the bed.

[tank1707]

Got the PC 300 for random misfire I checked the mad sensor looked pretty clean but can't tell since the car starts fine all day except for early mornings anything else?

[austinairport]

Check your ignition system.

How fresh are your spark plugs?

When were your spark plug wires replaced? (at 75,000 you really should change your plugs and wires.)

It also could be a bad coil pack.

[tank1707]

Maybe the starter? And I changed the plugs and ignition coil both at about 70k and it seemed to help pretty well but like I said the problem is cold mornings after a long so at night. I Aldo found a clip missing from the housing on my filter by my maf and it wasnt sealing down the housing all the way and that seemed to make it idle easier and somewhat helped the cold start but its still a little rough and shakey

[austinairport]

Well, if you're getting P300 (random misfire code) chances are the issue is with the ignition system.

What plugs did you use? Were they gapped to OEM spec?

[tank1707]

The plugs were Bosch and yes they were OEM spec I didn't have any problems after I replaced plugs and ignition coil but now it could he the maf sensor because it had been replace with one that is a toyota delco one do maybe there? And also I ran the engine turned it off and was getting a hissing sound every minute or so, maybe a pcv hose or vac leak?

[austinairport]

When my MAF died I replaced it with a a similar MAF (Not OEM, mine says Toyota on it as well.)

The hissing could be a number of things. Depending on where it is emanating from, it could be the fuel pump, or throttle body.

[tank1707]

Well I just cleaned the maf it had some grime on one side and cleaned the throttle body it wasn't to bad but was dirty and I also put some injector cleaner in my tank to see if it would make a difference even tho I had them fully serviced 6000 miles ago. Later when the maf is good and dry I'm going to try and check vac leaks, thanks for all your help and advice. l update in a day or so o see if anythings changed but if you think or anything else let me know!