Problem to start when the engine is hot

[LuisCarlos]

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.

Yes, I knew was another different system, injector, ISC, IAC, and of course the ECU, but about mixture air-fuel I din't know exactly, that's OK now..


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.

The TBI is brass colored too, is the same engineering that throttlr valve.. Have including a monument in water pipes Induetries, is very curious..



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/?

Yes, I have understood that, in the last test pinching ISC air hose, and clossing bleed screw to the end, the engine continued running, don't stall, for that have to be a leak..

the videos all say private. with sad face in player....
ok we work leaks next?

I'm sorry about..
Today, I'm going to see to my brother to send videos in a correct way.. But my videos in YouTube are for the public not in a private way, so I don't know what happening..



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.?

1º- The old TBI during long time working as normal, but it began to failure, that was what happened, when started in could r.p.m were 800, and in hot was very difficult to balanced the idle, consume a lot of fuel, smeaalling very bad, and doesn't passed Technical Inspection..

2º-So the mechanic got another TBI in a scrapping of cars where there are so mny cars to sell to scrap industries, and they remove some parts to sell to everybody, particular person or workshops cars ..

3º- But that old TBI faillure also, when started in could idle was about 1000 r-p-m, no more, and when the engine in hot and the idle was in traffic light or in traffic jam, the idle increased at 1500 r.p.m and never droped to 800 r.p.m..


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..

[color=#C71585]Yes, I'll ask him these question and more..
You know the mechanic is a good man but he's very stressed, his son told me 'my father are heart problem, he want to do everything to satisfy all clients '..
His workshop is always full of cars.. He forgot to fix a srew fron the plastic cap above the TBI, and I found other screw above the battery, it was the screw that is supporting the fuel metal pipe that come from the fuel tank and connect to TBI with two screw, it's fixed with a ring rubbert..
I also found above the battery the bleed rubber plug..

But what to do? At least he got the new TBI to half price, he's uncle of a friend long, he has good intention to do everything but some time faillure because want to do everything very fast..
I took the vitara there because he's the only has Suzuki OBD.. When I went to ask in another workshop, they don't have Suzuki OBD..

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)

Yes, I asked him about new base TBI gasket, he said he put the right gasket blocking the five holes in the plenum, but I'm not sure, I'll open it if is necessary, of courese

Reasons to replace a TB are: (what was yours?)
1: IAC bad. (RIP one TB) (can not be replaced, as a sub assembly)


[color=#800080]Ye, it's integrated in TBI.

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...

Anyway, I told him to get a new TBI, and because TBI is now I think we have a huge leaks, according at your information..
I'll send you the test blocking the mean air entrance and how the engine don't satall and the sount about air leaks..

I'll do another pinching ISC air hose and clossing bleed screw again..

Cheers !! and thanks again..