decrease base rpm 1990 toyota camry v6

[bingroy]

1990 toyota camry V6. Did an overhaul of the exhaust system and oxygen sensors recently. However, while getting thaty done, the mechanic increased the base rpm of the throttle. Earlier the engine used to idle at 1000 rpm, now it does around 1200. How do I get my idle rpm back to 1000? Thanks for the suggestions.

[REN69]

You posted this in the Corolla section, so I'm moving it to the Camry section for you.

BTW, I'd take it back to the mechanic and tell him to fix it, if he increased it he should be able to bring the idle down.

[atobe]

if it's anything like the I4 engine... there should be a screw you can turn near the throttle body that'll decrease the idle rpm even though 1k is still high should be around 600-800

[bingroy]

Thank you Mod I apologize for the error.

Before I make a trip to the mechanic, I want to see if it is something simple that I can try myself.

Atobe, Where will the throttle body be located? My throttle cable goes across from the left hand far corner across to the right hand (behind the battery) next to the vacuum manifold. Thanks in advance.

[bingroy]

Let me give a more thorough description of the sequence of RPMs observed. Note I have an automatic transmission.

RPM @ right after turn on the ignition: around 1500 rpm

RPM @ shifting to reverse or Drive (without pressing the gas throttle): 1000 rpm

RPM right after that (what would be 1st/2nd gears in manual transmission): progressively increasing from the idling rpm of 1000 to around 2000, then drop to 1500 (in what would be third gear).

Does this engine rev profile seem okay to everyone?

[TBayToyotaBoy]

Okay, my V6 is a 5-speed but my four-banger Camrys were both autos. The rpm characteristics for all Toyotas of this vintage are similar: high revs right after start-up (my V6 revs to 2300, my Celica revs to 2000, and IIRC the 4-cyl Camrys rev just as high on cold start).

Once the engine has come close to normal operating temp, the revs should drop down to 750rpm (stock). 800rpm idle is nothing to worry about, but anything higher is just too high.

On the throttle body (the aluminum intake piece that the black rubber snorkel clamps on to), there is a little spring arm where the throttle cable seats. As you let off the gas, this mechanism springs-back to idle. There is a little threaded stud with two tiny nuts on it that holds the throttle from retracting any farther, and your mechanic may have adjusted this too far forwards (it is now stopping the throttle cable from retracting the mechanism to proper idle). If you re-adjust it about 1/8" further back (towards the driver's side of the engine) it should bring the rpms down to normal.

If you're stumped, I may be able to dig-up a pic. Look at the little screw in the fourth pic down in this thread (the screw is painted yellow, and it's aligned vertically instead of horizontally on our earlier V6's):

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