So I have a 2002 s2000 104k. Long story short the Car sat outside for about 7 months(I would fire it up here and there just to let it run a bit) through the winter. First couple of weeks after I started driving again I would notice it bug out on the freeway once in a while, didnt pay much attention 2 it thinking it might be from the old gas that sat for 7 months, now couple months later the car got so bad it almost always dies when coming to a stop, buggs out badly when driving slow in 1 or 2nd gear. The crazy sh@t is, NO CHECK ENGINE LIGHT!! Changed the sparkplugs, everything else seems fine. At one point noticed a Pending Code(P1457) on my Scanner, but I dont think its my EVAP as it never actually became a CEL.
WHAT THE F%^@&CK can it be? I am going cazy, the weather is super nice but I cant even drive my car.

ALSO, forgot to add, the engine mainly buggs out when in gear, when I have it in neutral and rev it up I dont see the same symptoms.

 

check your throttle plate and see if it's dirty. smell the gas, does have this kind of putrid/old odor? if you smell that then you know the gas is old.

the 1457 has very little relevance on your drivability problem. if i remember it's a small leak or loose gas cap dtc

i would do those above things first since they are the most simple and more relevant since your car was sitting for a while.

 

I have refueled the tank several times since then, so its not the gas. How would a dirty throttle plate cause an issue such as this one?

Update: Early this morning it was being weird and wouldnt start very easy, I could also smell unburnt fuel(I am guessing it was coming from the exhaust). Acted up early morning as stated above but later in the day Drove my car and for the first 10+ miles it drove perfect then started acting up again. Thus said it has yet to stall once since this morning but it has been warm out all day. Could it be a coil? I have never seen cars with bad coils not pull a CEL. F@CK>........... This is giving me so much headache.

 

throttle plate because when you come to a stop, you let off completely off the throttle and the plate closes. the plate is not completely closed as to let some air in (with the help of the IAC motor/valve) to let the vehicle idle. if there is build up on the throttle plate, sufficient air cannot be let in to let the vehicle idle. in some cases where the IAC valve (stepper motor) is dirty/sticks it will cause idle to flare up and down as the motor/valve is trying to compensate for the insufficient flow of air

possibly, the fuel injectors could be clogged with some crap. in most cases, it will throw a dtc but not all the time. i would check them only if you can verify the culprit is fuel related. if you do decide to check them, most injectors have a tiny screen to block debris-sometimes they can get clogged (haven't seen one yet).

 

When was your last valve adjustment?

 

Change fluids, check clutch system, if its caused by being in gear i suspect something bout trans is causing it. Change trans, diff, and engine oil. Pull off intake and clean manifold with a little mani cleaner. Then get some nice premium gas, put some injector cleaner in it, i use half the recommended cuz i hate doing it. also pull off yoir iac valve and clean it out. All diys can. Be found here. I suspect its going to fix it tho