2001 sohc idle running higher than normal

[mwood1985]

what would cause a 2001 sohc t ohold an idle at around 1000 in park or neutral but drop back to aroud 5-600 when its in gear. and it revs up to like 2500 on start up. just started doing it the last few days. ive got 155k on the clock. im figureing vaccume leak maybe but anybody got any suggjestions

 

[cr_the_machinist]

I would check the the IAC, MAF, and TPS. Use a good digital multimeter to see if they are within spec. Most the voltage and ohm specs should be in the Tech section of TRS or in a good auto service manual (ex. Haynes or Chilton). Check for dry rotted vacuum hoses (like the PCV and EVAP vacuum hose). I've been through this with my 99 4.0 OHV. No real upfront answer. Just test and replace as needed. Hope that helps a little.