yes, they did sell carb cars in Europe. in 1996, (not one here, they are all illegal here starting about 1988) last carb here...1994 (Light truck) : Isuzu[11]
the TBI is no a carb. there is no relationship at all, from a CARB to TBI. zero.
TBI is just single injector , injection but the injectors is in the Throttle body, , our 1996 is MPI port injected x4. all are here. every one.
the butterfly name is pure mechanical engineering, name for a valve that when removed looks like a butteryfly,
butterfly valve, (aka in the car world as the throttle plate, etc)
back in the olden days, all carb books called it the butterfly valve. why? because we removed it and cleaned it and it looks like a yellow butterfly removed.
it's brass colored, yellow. when you open that valve, the engine receives maximum air, it is in fact just an AIR VALVE.
https://en.wikipedia.org/wiki/Butterfly_valve
on your car, the TV (butterfly ) is 100% (99.9%) closed at idle and supplies 0 air, nada.
drops "next to 0 in gauge toy," that is like 200 to 400 rpm so is good. the toy gauge is fully able to diagnose any ISC, or do calibration of ISC.
the lower the rpm the engine runs, that means it is STRONG, and has good compressing, etc. but your's failed to stall.
keep in mind the toy dash gauge is very non linear below say 500 rpm. (analog toy it is, ) but is fully usable for many things.. if not bad.
if you just do 2 things, this proves it:
pinch the ISC air hose, and turn the bleed screw CW, as you turn the screw, bleed, the air goes to zero and engine must stall.
must stall or you have leaks.
that is all there is to leaks tests.
Math:?
all-air = ISC + bleed. (Algebra) HOT. (at idle)
all-air = 0 + 0 ( there is no air at all, engine can NOT RUN with 0 air.) the first zero is the pinch, the 2nd zero is the bleed closed CW.
see my math here/?
the videos all say private. with sad face in player....
ok we work leaks next?
my thinking now (you never told me why the old TB was bad,,,,,,)"the word "scraping" alludes me as to what that was) sorry....
MAYBE the old TB works, ok.?
because your mechanic does not know how to DISCOVER
1 vacuum leaks?
2 prove it leaks (pinch tests) ISC check , duty checks.
3 and what exactly is leaking. (lots of test or smoke machine)
4: has no idea how nor why Dutycycle must be checked first (old TB) and set on the NEW TB..
there is a huge vacuum running, there in the plenum (plenum = induction system below the TB throttle plate)
and all leaks there, suck air. and all leaks there, cause the ISC to go nuts. (now or soon as all leaks never fix themselves; they get worse)
Reasons to replace a TB are: (what was yours?)
1: IAC bad. (RIP one TB) (can not be replaced, as a sub assembly)
2: injector bad, replace it. not TB.
3: ISC bad, replace it , not TB,.
4: throttle bore damaged, due to TB butteryfly plate set wrong.
5: throttle shafts worn so bad at TB butterfly shaft ,the suck air. (just like carbs did for 100 years ,same reason) can cause #4
6: gross ice damage, yes, water freezes and wrecks anything...
7a: something broke off TB, a nipple or?
8: dash pot bad, yes, those can be very hard to find...
the TBI is no a carb. there is no relationship at all, from a CARB to TBI. zero.
TBI is just single injector , injection but the injectors is in the Throttle body, , our 1996 is MPI port injected x4. all are here. every one.
the butterfly name is pure mechanical engineering, name for a valve that when removed looks like a butteryfly,
butterfly valve, (aka in the car world as the throttle plate, etc)
back in the olden days, all carb books called it the butterfly valve. why? because we removed it and cleaned it and it looks like a yellow butterfly removed.
it's brass colored, yellow. when you open that valve, the engine receives maximum air, it is in fact just an AIR VALVE.
https://en.wikipedia.org/wiki/Butterfly_valve
on your car, the TV (butterfly ) is 100% (99.9%) closed at idle and supplies 0 air, nada.
drops "next to 0 in gauge toy," that is like 200 to 400 rpm so is good. the toy gauge is fully able to diagnose any ISC, or do calibration of ISC.
the lower the rpm the engine runs, that means it is STRONG, and has good compressing, etc. but your's failed to stall.
keep in mind the toy dash gauge is very non linear below say 500 rpm. (analog toy it is, ) but is fully usable for many things.. if not bad.
if you just do 2 things, this proves it:
pinch the ISC air hose, and turn the bleed screw CW, as you turn the screw, bleed, the air goes to zero and engine must stall.
must stall or you have leaks.
that is all there is to leaks tests.
Math:?
all-air = ISC + bleed. (Algebra) HOT. (at idle)
all-air = 0 + 0 ( there is no air at all, engine can NOT RUN with 0 air.) the first zero is the pinch, the 2nd zero is the bleed closed CW.
see my math here/?
the videos all say private. with sad face in player....
ok we work leaks next?
my thinking now (you never told me why the old TB was bad,,,,,,)"the word "scraping" alludes me as to what that was) sorry....
MAYBE the old TB works, ok.?
because your mechanic does not know how to DISCOVER
1 vacuum leaks?
2 prove it leaks (pinch tests) ISC check , duty checks.
3 and what exactly is leaking. (lots of test or smoke machine)
4: has no idea how nor why Dutycycle must be checked first (old TB) and set on the NEW TB..
there is a huge vacuum running, there in the plenum (plenum = induction system below the TB throttle plate)
and all leaks there, suck air. and all leaks there, cause the ISC to go nuts. (now or soon as all leaks never fix themselves; they get worse)
Reasons to replace a TB are: (what was yours?)
1: IAC bad. (RIP one TB) (can not be replaced, as a sub assembly)
2: injector bad, replace it. not TB.
3: ISC bad, replace it , not TB,.
4: throttle bore damaged, due to TB butteryfly plate set wrong.
5: throttle shafts worn so bad at TB butterfly shaft ,the suck air. (just like carbs did for 100 years ,same reason) can cause #4
6: gross ice damage, yes, water freezes and wrecks anything...
7a: something broke off TB, a nipple or?
8: dash pot bad, yes, those can be very hard to find...
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