LandShark

Hey guys i need a little insight on something. i just moved to colorado a week ago and my S2k is sporadically acting weird when i start it in the cold. This has happened the last 2 winters i've owned it, where when i start it the starter will stick occassionally and make a grinding noise for a second or two, simlilar to if you held the start button in after the car was already running. this has only happened to me when it's cold out but here in denver the issue is different

My new issue, and this has happened to me twice now, is that now when the car makes that god awful noise the car bogs down to around 800rpms and sits there stuttering, after which i freak out and cut the car off, then i nervously restart it and the car runs fine. very odd

im not sure if the fact that im at a MUCH higher altitude so suddenly is playing a factor in this. Could it be the ecu freaking out from the air density being so low here compared to memphis? Ugh please if someone can help me figure this out id really appreciate it. I mean hell it's bad enough my car is now god awful slow because it cant breath up here lol

Sleepr 240sx

You should definitely reset your ECU as it will need to relearn now that you are in such a drastic change of environment in regards to air density. Technically you should do this even if there is a small change but its nothing you would usually notice. In your case it would be a pretty big leap and I'm pretty confident it could be the cause of your troubles.

S2_4SHOOR

more info on resetting ECU.

you're not the only one who's having cold start up problem. It's very common. Seems like ppl are just driving it till it dies and replacing starter in the end.

tdonovan07

Would love an answer on this since I have the screeching noise at cold startups also. I have been thinking its the starter but not 100% sure.

Sleepr 240sx

The screeching noise is your starter. That is your starter solenoid sticking because of the cold. Will usually only happen after being left in the cold overnight or for a longer period of time. If it happens every time you start your car then your starter is most likely on its way out and you should replace it soon or be left stranded.

Resetting the ECU only has to do with the fact that his car was idling rough after startup, it has nothing to do with the starter solenoid sticking.

LandShark

Thanks for the replies guys. i didnt mention this but whenever i got my ecu swapped to the 03 i followed a member on here named gernbys advice and just kept the ecu backup fuse pulled, because supposedly it makes the car run a bit leaner for some extra powa . I had it pulled for 2 years and the car ran fine, however the first time this weird bog occurred when i got to CO i immediately put the fuze back in thinking the exact same thing. i figured the car needed to relearn the new parameters for colorado, and for about 2 days the car would startup fine (excluding the occassional starter stick) but then yesterday the car did it again.

So the only thing i could think of, if this is in fact an ecu learning curve issue, is that maybe my car needs more time to learn whats going on here. Since the roads are so iced over and i DESPERATELY need new tires (giant understatement lol) i haven't been driving it as much as usual, maybe like 50 miles since this occured, so this may be the case. Ill keep ya posted on this and if anyone else has some insight im all ears. Thanks again guys

s2cho

Hey i live in colorado too! i drive a 02 spa but im trying to go back to stock. i noticed running 5w-30 will help a TON with starting in our weather. but the most effective is leave the key in at the 2nd position for about 20 secs and then start the car. the cars fuel regulator needs to build up pressure. if you let the fuel regulator build pressure it seems the starter makes less of a screeching sound and the engine turns on strong. haha and tires are a must, but i run all seasons in the back and summer in the front atm and im fine through the icey roads. where in colorado are you living? im in aurora!

SgtB

Don't reset your ECU. It already has a barometric pressure sensor in it to account for altitude. Is your battery good? The cold will push a dying battery past it's breaking point. The grinding could be the battery dropping off quickly and the solenoid doesn't have enough juice to stay engaged, resulting in a starter grind.

LandShark

Thanks for the advice man! Ill def go ahead and try letting the car sit for a bit longer with the key turned to see if that helps. Im already running 5w-30 castrol sythetic, so Im good in that area. I had it changed just before I made the long 18 drive here from Memphis. I’m in Lakewood btw, not sure if auroras close to here or not. I gotta ask how is it owning an s2k in the winter here man? People keep freaking me out saying it's going to be terrible since my s2k is my daily, but i love my car and I don’t ever want to get rid of it to go the awd route everyone seems to drive here. Also I really dont know anyone here, but I’ve wanted to go and meet up with some fellow car enthusiasts. Are there any clubs that you know of, maybe some group mountain drives? The only time I’ve really driven my car up here lately is up through the mountains and it is sooooo awesome, almost like car heaven lol. I just got a set of coilovers and the Memphis roads were thrashing my car, so now it's been awesome to test out the new setup on these crazy roads =)

LandShark

Trust me man Im done reseting the ecu now that im up here, but thanks for the advice. I don't think it's the battery because i had it replaced about 8 months ago. It's been snow covered since yesterday so i haven't been out to start it to see if it would mess up again. I did take it out to bring my sis to work 2 days ago and it started up fine with the exception of the grind. I guess time will tell, especially since it's only getting colder here.