12-08-2018, 03:57 AM
sorry DP or this dashpot is only on all 8v G16s,
it is also called the fast idle vacuum servo) it runs for 3 to 15 seconds, mostly.
the word is old and silly, its neither DASH nor a POT.
in the old days of carbs they hand this same name device that is either a shock absorber or is device to raise idle with AC turned on.
then in 1989 it is now full time device, that is only on 8v for preventing liquid fuel puddling under the TB plenum box below.
see here 91. (89 is near)
![[Image: TPS-testing.html#8v-gage]](http://www.fixkick.com/sensors/tests/TPS-testing.html#8v-gage)
here is my DP page the DP adjuster is seen here just to the right, of the DP plugger.
http://www.fixkick.com/IDLE-AIR/Dash-pot.html
fast idle is always air leaks. too many.
lots of causes. huge. really, were a vacuum exists air wants to leak badly.
TB throttle valve plate gummed up, as it hits the bore is ticks, so force it closed by hand see TV close bingo it was stuck.
the DASH pot retracts , just watch it if it retacts in your 4 stated seconds, and retracts leaving a gap, then DP is OK> unless rpm is only 4000 DP active.
next is ISC sticking top of TB see 2 wires to that? ISC is how ECU keeps 800 RPM hot. it is the idle speed control regulator
the IAC in the base of the TB is closed at 150F, if not it is Bad.
but cold the IAC will be near open or fully open at or 0.060" at -10f (using numbered drills shanks by me in freezer) only I have this data.
http://www.fixkick.com/sensors/tests/IAC-T-tests.html
next is vacuum leaks, for sure if hot idle is not 800 you do have leak.
hot engine 180f+ only 2 air paths exist, ISC and TV,. all others must be closed.
all vacuum leaks the MAF sees it and measures it and adds fuel (to match) and idle always goes higher on this car.
what happens at 180F? idle?
good luck to you !
it is also called the fast idle vacuum servo) it runs for 3 to 15 seconds, mostly.
the word is old and silly, its neither DASH nor a POT.
in the old days of carbs they hand this same name device that is either a shock absorber or is device to raise idle with AC turned on.
then in 1989 it is now full time device, that is only on 8v for preventing liquid fuel puddling under the TB plenum box below.
see here 91. (89 is near)
here is my DP page the DP adjuster is seen here just to the right, of the DP plugger.
http://www.fixkick.com/IDLE-AIR/Dash-pot.html
fast idle is always air leaks. too many.
lots of causes. huge. really, were a vacuum exists air wants to leak badly.
TB throttle valve plate gummed up, as it hits the bore is ticks, so force it closed by hand see TV close bingo it was stuck.
the DASH pot retracts , just watch it if it retacts in your 4 stated seconds, and retracts leaving a gap, then DP is OK> unless rpm is only 4000 DP active.
next is ISC sticking top of TB see 2 wires to that? ISC is how ECU keeps 800 RPM hot. it is the idle speed control regulator
the IAC in the base of the TB is closed at 150F, if not it is Bad.
but cold the IAC will be near open or fully open at or 0.060" at -10f (using numbered drills shanks by me in freezer) only I have this data.
http://www.fixkick.com/sensors/tests/IAC-T-tests.html
next is vacuum leaks, for sure if hot idle is not 800 you do have leak.
hot engine 180f+ only 2 air paths exist, ISC and TV,. all others must be closed.
all vacuum leaks the MAF sees it and measures it and adds fuel (to match) and idle always goes higher on this car.
what happens at 180F? idle?
good luck to you !
http://www.fixkick.com