Car Shuts Off When Idle

[hershy67]

Hey

Does anyone know why my car's engine would stop running when I'm idle?? After a few minutes while I warm up my car, the RPM needle goes down about half way in between 1x1000 and 0x1000 on the instrument cluster (car also shakes/trembles while the needle drops in between). Then the engine will eventually turn off with the check engine light on. This also happens while i am at a stop light. Could this be the cause of a faulty o2 sensor??? I doubt it's the alternator because I had that fixed 2 years back along with the p/s pump. Maybe a MAF?? I have a 93' SC400 with 131k on it. Thanks.

[SKperformance]

try cleaning the throttle body then check the distributer and coils

[TWINTURBO619]

try cleaning the throttle body then check the distributer and coils

it's probably your airflow ratio. there's a little screw by your throttle body that will let you adjust the airflow ratio. turn it up a bit and this will start raising your idle. your car will start sucking more air and make you go a little bit faster. but i bet that's what the problem is. good luck

[AWJ]

You need to have the mil procedure run. Pull the code. To find the answer. Off the top of the head - it is probably an idle adjustment as the others state. But if you have a dirty air filter, fuel filter, or otherwise - those things will contribute. Run the procedure to know what the computer is saying is wrong. If you need the procedure in basic form - pm me with your e-mail addy. I will send it over. Otherwise, consult a competent mechanic.

[hershy67]

I'ma take it to the dealer this weekend to see whats up. I'll let you guys know...

[kaiylee]

Does the dealer find out anything?

[hershy67]

didnt go yet. had to replace the lower arms. i havent had a problem since i posted this this thing up. i will let you know though.

[vasso]

I had a similar problem and my car engine also stopped twice, dealer told that sensor THROTTLE POSITION (FOR E.F.I) is bad -200$

I have to replaci it i guess..

tom

sc400

[AWJ]

tps, idle adjsutment, or fuel pump ecu above and beyond the obvious maintenance items. It is possible if the tps is found to be root cause that it is merely mislocated, dirty or otherwise serviceable and not necessarily bad to the point of needing replacement. But then again, it might need replacement. Unless you are able to test it yourself, you won't really know. 200$ could be reasonable though for labor and a job well done.

[SleepySC]

Same as other post.

Check the engine codes first (do a search, pretty simple using a paperclip)

Fuel Pump ECU problem is one of the MOST common problems with the SC and LS. The problem does NOT have an engine code so you will not know unless you do the bypass. The fix is SIMPLE, just connecting 2 wires.

Stalling is the common symptom.

If your car does not throw any engine codes, try the fuel pump ecu fix (bypass) first. You will save yourself a lot of time and money (my own experience--- tune up, replaced throttle position sensor, cleaned throttle body didn't help. Fuel filter has to be significantly clogged--- not likely, but plausible i guess).

Good Luck.

[UCF3]

didnt go yet. had to replace the lower arms. i havent had a problem since i posted this this thing up. i will let you know though.

I experienced a similar problem after being rearended. It stabilized after a couple of days, but I was going to check the fuel filter for crap. It felt like the engine was starving for fuel, and the most logical theory was, the sutt from the filter was cloggling the valves.