just he heater core, is leaking, check near passengers toes for signs of leakage. or just the hose as it just passes through the fire wall, almost no hose this old runs at 12psi, not that old.
see core here?
rule 1, never twist this hose or it breaks off the core nipples, use cutting tools to remove hoses, then slide new hose on. zero damage.
http://www.fixkick.com/Cooling-engine/he...index.html
great questions, all !
the eCu controls idle, so if you change the bleed screw, and idle changes, that means the ECU lost control of IDLE speed, the ecu sets idle at all times. no you or me, ever.
how are you setting idle , via what device, there are 3 ways, to change idle speed. only one is correct and only one is for dutycycle not idle.
My question on this answer why do I have to adjust idle and timing so much?
first off , spark timing requires, 800 rpm , hot, accessories off, and idle is not settable.
let me explain,
there are 3 throttle cables. to be set wrong, they must all 3 be set to slack. or idle will fail, due to them pulling on the throttle illegally.
throttle cable, 3speed kick down cable. and the cruise cable, my car has only 1, its 5speed.
the idle switch must be closed, or idle controls are dead, and this failure you will notice that the bleed screw changes idle speed, that is because the ISC is dead.
There are no mech. that know these early 91 cars. 89/90 even worse. they dont , nor how to adjust them. (that is because on newer cars all these settings are Fixed)
you start the car, did the dash pot, retract 100% you will see an air gap between that DP rod and throttle cam. this means its retracted and not messing up idle, at all, (not touching)
now with the car hot idle, pin the cool ISC air line 100% RPM must fall to like 400rpm or near stall.
if it dont do that , that means there are air leaks (vacuum leaks) and is why the ISC has lost control.
this screw with white paint must never be fiddled or changes, or the ISC will FAIL. (the white paint is the warning, dont touch me)
http://www.fixkick.com/IDLE-AIR/cold-air-n2bw.jpg
the ISC can not correct 2 gross errors.
1: hug air leaks that when it closes RPM is still over 800 RPM.
2: EGR stuck open (or gross engine timing retardation) RPM is way too low , such that opening the ISC 100% the ECU can not attain 800RPm
this is the limits to the ISC command authority. it can not correct for gross errors.
the TPS pins A to D are here
http://www.fixkick.com/TPS/TPS-p91.JPG
see test 4
here
http://www.fixkick.com/sensors/tests/TPS...witch_test
on car test. do this at any time hot. (hot engine)
the car, idle test , is to turn on headlights, and blower fan and defrost if you have it, does IDLE drop, low? bingo no idle controls at all.
timing off
timing off a hair is no big deal. you will never get it perfect.
if it bounces like crazy ( normal not in freeze mode) but if it bounces in freeze mode, that too is a clue that the idle switch is not closed.
the setting of timing, its mandatory that the idle switch must be closed,
why? because the ECU things your are driving, and when it thinks that , it suspends idle.
The ecu believes the switch 100 % all the time.
just ECU caps need checking for leaks (acid spills or signs of that)
the FSM page is here.
for the cal.
http://www.fixkick.com/TPS/TPS-p92.jpg
the correct feeler gauge for 1991 is 0.016" threshold and the GO gauge is 0.012" most go to zero volts.
my tps page as a table listing all engines all feelers used.
it is fairly critical.
if set wrong, no idle.
if set to open late this causes TIP-in hesitation. (ISC fights your right foot , in this case, very bad that act)
the FSM page is not option, one can not guess it to work right. it must be set.
Idle controls are what is called a SERVO.
the ECU and the ISC from a SERVO loop
when active , the ECU holds idle at 800 RPm (in a closed loop style) even with alternator sucking 50amps. , the Power steering moved.
the bleed screws set the center point of this servo, to 50%
this allows the ISC to add or subtract air, 50%, this adjustment centers the ISC on a hot , no load engine.
on a working kick the bleed screw never changes idle. that is unless , you dont exceed the range of the ISC.
as air gets colder it has more oxygen, and the ECU adds fuel and the engine wants to race. the ISC corrects that too.
it also corrects for engine wear and lost compression.
it also adds 200 rpm for A/C on.
with the ISC dead, the engine rpm will vary by all the above.
see core here?
rule 1, never twist this hose or it breaks off the core nipples, use cutting tools to remove hoses, then slide new hose on. zero damage.
http://www.fixkick.com/Cooling-engine/he...index.html
great questions, all !
the eCu controls idle, so if you change the bleed screw, and idle changes, that means the ECU lost control of IDLE speed, the ecu sets idle at all times. no you or me, ever.
how are you setting idle , via what device, there are 3 ways, to change idle speed. only one is correct and only one is for dutycycle not idle.
My question on this answer why do I have to adjust idle and timing so much?
first off , spark timing requires, 800 rpm , hot, accessories off, and idle is not settable.
let me explain,
there are 3 throttle cables. to be set wrong, they must all 3 be set to slack. or idle will fail, due to them pulling on the throttle illegally.
throttle cable, 3speed kick down cable. and the cruise cable, my car has only 1, its 5speed.
the idle switch must be closed, or idle controls are dead, and this failure you will notice that the bleed screw changes idle speed, that is because the ISC is dead.
There are no mech. that know these early 91 cars. 89/90 even worse. they dont , nor how to adjust them. (that is because on newer cars all these settings are Fixed)
you start the car, did the dash pot, retract 100% you will see an air gap between that DP rod and throttle cam. this means its retracted and not messing up idle, at all, (not touching)
now with the car hot idle, pin the cool ISC air line 100% RPM must fall to like 400rpm or near stall.
if it dont do that , that means there are air leaks (vacuum leaks) and is why the ISC has lost control.
this screw with white paint must never be fiddled or changes, or the ISC will FAIL. (the white paint is the warning, dont touch me)
http://www.fixkick.com/IDLE-AIR/cold-air-n2bw.jpg
the ISC can not correct 2 gross errors.
1: hug air leaks that when it closes RPM is still over 800 RPM.
2: EGR stuck open (or gross engine timing retardation) RPM is way too low , such that opening the ISC 100% the ECU can not attain 800RPm
this is the limits to the ISC command authority. it can not correct for gross errors.
the TPS pins A to D are here
http://www.fixkick.com/TPS/TPS-p91.JPG
see test 4
here
http://www.fixkick.com/sensors/tests/TPS...witch_test
on car test. do this at any time hot. (hot engine)
the car, idle test , is to turn on headlights, and blower fan and defrost if you have it, does IDLE drop, low? bingo no idle controls at all.
timing off
timing off a hair is no big deal. you will never get it perfect.
if it bounces like crazy ( normal not in freeze mode) but if it bounces in freeze mode, that too is a clue that the idle switch is not closed.
the setting of timing, its mandatory that the idle switch must be closed,
why? because the ECU things your are driving, and when it thinks that , it suspends idle.
The ecu believes the switch 100 % all the time.
just ECU caps need checking for leaks (acid spills or signs of that)
the FSM page is here.
for the cal.
http://www.fixkick.com/TPS/TPS-p92.jpg
the correct feeler gauge for 1991 is 0.016" threshold and the GO gauge is 0.012" most go to zero volts.
my tps page as a table listing all engines all feelers used.
it is fairly critical.
if set wrong, no idle.
if set to open late this causes TIP-in hesitation. (ISC fights your right foot , in this case, very bad that act)
the FSM page is not option, one can not guess it to work right. it must be set.
Idle controls are what is called a SERVO.
the ECU and the ISC from a SERVO loop
when active , the ECU holds idle at 800 RPm (in a closed loop style) even with alternator sucking 50amps. , the Power steering moved.
the bleed screws set the center point of this servo, to 50%
this allows the ISC to add or subtract air, 50%, this adjustment centers the ISC on a hot , no load engine.
on a working kick the bleed screw never changes idle. that is unless , you dont exceed the range of the ISC.
as air gets colder it has more oxygen, and the ECU adds fuel and the engine wants to race. the ISC corrects that too.
it also corrects for engine wear and lost compression.
it also adds 200 rpm for A/C on.
with the ISC dead, the engine rpm will vary by all the above.
http://www.fixkick.com