So ever since I've had the s2k, I had problems with the throttle. Everytime I accelerated the gas and let go, the RPM's would drop way below 500 rpm and the engine would almost die. However, the engine would never die. Then the rpms would immediately go back to 750-1000 like normal.

I recently tried to fix this by buying a new map sensor. When I installed it and reset the ECU, I waited for about 30 minutes with the car just on. Then I would accelerate, and the problem was worse. The rpms would drop less. Maybe it's because I haven't driven? or maybe it takes awhile for the map sensor to arrange itself?

I don't know but this is pissing me off lol. Has anyone else had this problem?

 

Try giving your throttle body a good cleaning if you haven't already. It's not a 100% cure, but it helps if your TB is gunked up with carbon/blow by deposits.

I've "fixed" 2 S2000 that were experiencing this problem with this method and a good ol whack of the map sensor.

You could try cranking up the idle screw to bring the idle up a bit if it's too low or bypassing the coolant lines to the throttle body as we never really encounter sub freezing temps to warrant a stuck butterfly. From what I gather, the idle does that when the engine suffers from heat soak.

 

try flushing or getting a new IACV

or intake air control valve

 

I had the same problem...if u look on the side of then engine if i remember well its the Idle air control assembly (IAC) you can see a pic of it if you do a search on here...the screw was going loose basically it was kind of stripped which is somethin i have no explanation to..but its kinna of a B**** to work on when ur engine is hot so try to check if that screw is loose and see what u can do! it solved my problem!

 

if none of that works maybe check your o2 sensors they can go bad and screw up your idle

 

Usually a bad O2 sensor will throw a CEL.

 

otis guru hurr!!!

he has all the answers. yeah the the screw over time just vibrates out and messes with the idle. that happened on my 95 ford pube GT. fix the problem right away!

 

I've had this problem. No light so I'm all too worried about it. "No light, no smoke, no problem" is my motto of choice. It does it for a day and then runs smooth for like two months. When it happens I just don't look at the gauge. Radio turned up so I don't hear it either.

 

Listen to this guy, he knows what he is talking about. The problem you have is very common amongst our cars. There is a write up on the site somewhere, I will search for it tomorrow. It teaches you step by step how to properly clean the TB. I did it to mine and problem was solved.

 

Also, I forgot to mention, take off your IACV and see if there is gunk in there. Most of the time, idle related issues come from there as well.