J20 engine trottle continues to drop

no engine stated, ! nor country. sold world wide with huge list if engines.
G16, J20, H25 , H27 , are common.
what?
if the j20 & up ,chain goes bad and you let go, catastrophic,
the engine pistons bends the head valves. unlimited damage.
what lives , is pure luck.
the G16 is free running and only a long walk home.

topic is cascade failures.

On top of the engine.You need to remove the ignition coils to access the spark plugs.

which engine? surely you know whats there, doing such radial work.
and why? do post why. id bet its not the pump, wana bet?
G16B engine
J20
H25, h27 or larger?
each is very unique in service, totally !

g16 takes, pan drop, and cam belt off and crank cog and pulley off.
J20.
here is the J20 page. below is that and obvious right?




and last the V6

see the pump below> inside pan?
here is the pdf of whole engine above

page 4 and 39
http://www.fixkick.com/engine/2.5L%202004%20Tracker/25L-2004-engine.pdf

if you need all steps its in the FSM book ! or alldata.com

can post them but need exact engine,

all answers are USA spec cars.

happy new year.
WHAT IS THE RPM>?
hot or cold engine? both key factors.
the a/c puts a large load on the engine
the engine J20 is powerful, and has idle controls
so now those controls are dead.
1: if engine has full power then its not due to lean bogging at idel
2: idle controls failing, ISC failure or failsafe mode.(pcm)
3; Seizing a/c compressor.

idle controls are suspended in fails safe mode
idle controls will fail of engine is real lean.
idle controls will fail if the engine is overloaded.

we check the a/c by hand to see if its ok.
we scan the PCm see if DTC ERRORS. SEE RPM AT 800
See coolant at 180F
we then make sure the engine at hot idle is at closed loop status
if not, we fix that first.

idle is last to fix, all else must be correct or idle will or can fail.
eg: running real lean, running rich and misfiring. etc.
Egr VALVE STUCK OPEN

AND lots more..... ask

Usually on idle (warm engine) this is OK.

You need to verify that you actually have oil pressure before continuing to drive. It may only be the sender or the gauge, but you need to verify oil pressure. The sender is on the right side of the engine block, remove that,pull your coil wire so the engine won't start, and crank it over. If you have oil pressure, oil will squirt out of hole.

see if you can pull the codes for vehicle ,,but it sounds like a idle air control valve,iac,,,or sometimes trottle position sensor,,,most the time you can take iac off clean part and trottle body

it sounds like a idle control valve if you keep your foot on the gas alittle does it stay runningif so does it sound normal if so it probably your idle control valve and to should be on the back of your trottle body also try cleanind the inside of your trottle body with a lint free rag and some trottle body cleaner make sure you open the butterfly and get all that carben out of there sometimes the carben build up will also cause a big drop in rpm.

it sounds like your speed sensor is going out you should replace it before it gets any worse

have you checked the coolant in the radiator? if overflow jug was empty radiator is probably low as well. always check when engine is cold. if you are low in coolant it will cause the fluctuation