High idle cold start

[Sean08ssv]

Hey guys wondering if anyone can help.
Not sure if related but i got my alternator replaced couple weeks ago as i had alternator warnings on dash etc..problem is fixed althou after a couple days when starting my car first thing in the morning and leaving work the idle has been sitting between 1500rpm - 1800rpm usually it sits at 500-600.. it seems to go away once the car has warmed up..also on 2 starts its really struggled to turn over, fires over but really rough like its gonna stall but comes good...
Its done this every day now for 5 days straight battery was disconected fornthe alternator repair woukd this play a role as the computer seemnto control everything but yeh i have no idea...today the idle was going up and down quite abit on first start up but was fine for the rest of the day..

Any ideas?

 

[MYVESSV8]

battery stuffed, clean maff, small vac leak, O2 sensor, is it tuned,otr,exhaust, what fuel, plugs,

 

[07GTS]

may have to do a throttle relearn if battery was disconnected for a while

 

[Sean08ssv]

Ok so i should mention its a 2008 ve ssv ute. Ive had it for 4.5 hrs ive had no trouble at all till past month alternator now this issue.. replaced battery 2-3yrs ago..its been very reliable till now

I have an dual 3inch cat back and otr but i installed that myself 4 yrs ago, exhaust was done around same time.. when susing it out today i noticed the rubber boot from otr to maf has cracked at the bottom so its not sealed you could poke ur finger throu it..trying to find another one atm..
I havent tryed to clean maf yet..
I haven't had it tuned just services when needed..

 

[Sean08ssv]

may have to do a throttle relearn if battery was disconnected for a while

Yeah ive read that on here i think i might do that tomorrow if it keeps happening

 

[07GTS]

fix that rubber boot first if its after the maf then it is un metered air which could cause a higher idle

 

[Sean08ssv]

Its in front of it, the airbox side..

 

[mr_s]

Sounds like the Battery could be on it's hind legs.

 

[Sean08ssv]

Really?
Its been fine everyday since my last reply so over a week. Today leaving work i was at the lights and the revs went up to 1500 twice, sounded like i was hitting the accelerater a couple times then was fine..also noticed my temperature is higher then usual. Its always been 108 ever since new alternator its been getting as high as 119

 

[Sean08ssv]

Sounds like the Battery could be on it's hind legs.

Really?
Its been fine everyday since my last reply so over a week. Today leaving work i was at the lights and the revs went up to 1500 twice, sounded like i was hitting the accelerater a couple times then was fine..also noticed my temperature is higher then usual. Its always been 108 ever since new alternator its been getting as high as 119