anacortes

Upon starting cold the 94 SC300 runs up to 1500 RPM which seems excessive. You get a real bump when slamming it in gear. Is this adjustable?

KahnBB6

iTrader: (5)

Does this go away once the engine temperature warms up? It could be related to a malfunction with the IAC-V (Intake IDLE Air Control Valve) unit or circuit.

anacortes

That's correct. Once warm it's normal. Thanks for the info. Bob

KahnBB6

iTrader: (5)

Bob, my apologies. I should have stated that IAC-V stands for the IDLE Air Control Valve. Check into that unit and if necessary the wiring going into it and the condition of the engine harness plug that goes into it. If it is malfunctioning, the OEM part should still be available. Same for the harness plug or repair wire terminals with seals.

If the OEM IAC-V is not available try looking it up on Rockauto under the Standard Motor Products, Airtex/Wells or other aftermarket brand.

anacortes

Will do. And, thanks again. Bob

RudysSC

Bob - that's about what mine warms up at during a cold day here in Denver. If it idles normally closer to operating temp I wouldn't sweat it any.

anacortes

Thanks Rudy. It just makes such a jolt as you put it in gear....makes me cringe. Bob

O. L. T.

iTrader: (17)

The TPS sensor is adjustable. rotate it slightly....... SLIGHTLY..... and see if it helps. You can change the idle RPM and shift immediately by unscrewing the sensor and making minor adjustments to it's position. I got rid of my shift issues 5 years ago or so with a simple change to the position of the sensor. Do not do that without marking it's original position. One way makes it shift harder, one makes it shift softer.

It's an after effect of doing so, it's not it's intended purpose. "it works". Meme attached for Lexus technicians.