slightly higher than norm. idle

[jimcreek]

this only happens every now an again.
while driving on city streets anywhere from 35mph to 45mph aprox. 3 miles when i come to stop light i can feel that i have to press on brake harder look down at dash and notice the check engine light on also noticed that that rpm slightly higher (900rpm to 950rpm below 1000rpm)normaly it runs 700rpm to 750 rpm.
it has happen 3 times in the last 2000 miles
light stays on and idle stays up from trafic light to trafic light until i cycle key off.
the first time it happened took to shop scaner reported timing sensor (cant remember dtc)
any help would be greatly apprecitive
you all have helped me in the past thanks again

[Turbine Doc]

Fridge man,
Check behind the glove box may be 2 loose wires there with odd looking connectors on them bare, when grounded sets high idle for plow or PTO mode, Dealer could not tell me what they were for when I bought the truck, by accident 1 day after swapping PCMs 1 grounded and I was at hi idle 900-1000 if IIRC

[jimcreek]

tim
thinks for the info my dash is loose from an ordeal with evaporater removal.
i will check an get back to you

[jimcreek]

one other thing would this set a dtc

[Turbine Doc]

Mine did not set a dtc, now that I have my book open if it is the PTO wires shorting they will be on center plug of PCM, C2; pin B7 1350rpm, or pin B8 1070rpm the B row is the lower row of the plug

[GARY PAGE]

One thing to check is the connection at the water temperature sensor. If this connection comes open it will increase idle speed to approximately 1000 RPM. If the engine was running for 8 minutes it will set the SES light. When the condition clears meaning some resistance is indicated in the circuit the SES light will go off. No codes are store for this event. Check and clean the connector at the sensor.

[kowsoc]

I believe also the air intake temperature sensor has something to do with idle speed. My 94 in colder weather will idle faster even though the coolant temp is right up. I'm guessing this is because of cooler intake temperatures. After under hood temps get warmer, the idle will be at the normal 637 RPM. I've found mine runs better and gets higher MPG with the front covered completely, even bumper holes, in below freezing temperatures.