Problem to start when the engine is hot

[LuisCarlos]

ok that TBI was banned here in 1995, so all 96s Up are MPI x4 injected. but im aware if this and is not a rule in EU, or SPAIN, all normal. this.

IAC?, Suzuki has never published the max rpm on coldest coolant ever here.
my guess is 2000 rpm ,max, I've seen 1500 on most, on cold days. (after dash pot does its thing) really if the engine oil is thick and engine stiff this varies) but if running 0w oil?, something else? or weak engine? (the speed will be a factor of air supply and engine friction(loads) , now)
try to keep in mind the difficulty starting in frigid weather, with that single injector and fuel puddling there.... (lots of AIR wins this)
its all the weakness of TBI, and why it's gone today..... (the CAT is dead cold, so this is a major source of pollution , then)

IAC hacking::
the problem with closing IAC cones, down , is that cranking the ECU assumes its open fully, (it has ECT temp tables for that) and injects based on that fixed table. (why fool any ECU,)?

if you close it down, then it goes too rich cranking!, can be a problem on real cold days, it will start with Dashpot open then starts and floods.
just something to consider, and that he ecu knows the air source of iAC = dash pot, cranking and first start)?

but on the other hand after 20 long years, the wax pellet is slow, weak and late to close. (prove it in a pan of water!)
i just use hot water in a pan to see that it does close 100% at 150f if it does, then its all i can do. really, for sure. (my camping stove works here)
next is the idle stop, Someone messed with yours.(more later)
The dash pot.
those 3-30 seconds are a variable in the ECU, It's hard coded software on ECT readings , who could change the ROM in the core of that processor?, (impossible right>?)
there is a screw on that DP device, lower that? yet? DP fast idle is in the book, the test is 2500 rpm i think, done HOT not cold and forced by hand.
cant change time but air flow yes, more later.... on DP
TV not closed, is FAIL TIME!
is the TB 100% closed, the TV valve is 99.9 % closed, it's only open enough to keep it from jamming, in fact will not pass water thru it , when tested.
so you have in effect the 91 to 95 USA setup, for 8v. ok, i know it very well, ran many tests on it , to use aftermarket ECU.
TV is set wrong more later....
TPS idle:
the idle switch, ok the tps has 4 pins.

rubber valve was opened according Suzuki Rhinoman Manual

(rubber valve what is that?) my guess. the non water heated, ISC? where is this?
these old cars, some parts are not sold now.... so actions must be taking to keep car running,
many have screwed in the iac, valve, one guy even blocked it. for ever. and must use right foot to start car. (skills)
One more point , if the ISC is active and the ECU cant seem to control idle, this ECU will HUNT THE ISC in the blind hope (dumb software) that i can find 800 rpm some why...... (but never off idle point)

this old car has a switch, (a crude carbon switch) inside the TPS
when it closes, it tells the ECU , hey, im at idle , turn on the ISC servo now, and kill EGR now. (etc)
if the switch is not calibrated and open there will be no iSC actions. it be dead now. and idle random. (load based, and air leaks based)
The J engines up dont have this switch, it just looks for 0.5v throttle voltage = idle active. but not G16s ever. it has a switch that must work.
TPS:
pins C and D here, on my TPS pages?
http://www.fixkick.com/TPS/TPS-p91.JPG

water temps are key, if the thermostat fails, (or is wrong) the ECU will punish you and the engine.
we use a IR gun to point at the water parts and make sure all hit near 180f,( some will be like 170f outside but inside 10f more)
http://www.harborfreight.com/infrared-th...xSEdoUTnuE
the thermostat housing and the ISC and IAC must flow water and be near 180f + (i run a 195 stat) they will not work , if temps at THEM get near 150f.
this is key to those to parts working and ECU tables all run off ECT reading BIG TIME. (and iat)
(thermostat bad or wrong or missing, or those tiny hoses clogged after 20 long years. all cause the IAC /ISC to fail.) we use the gun and not guess.
the dash gage has no numbers it not useful ever. it's a toy. use real measuring devices to do testing.

wrong TV, I can not guess why , only can show what is wrong for sure.

It's open about two milimeters separate from the screw sealed in factory in down side

, in this moments the idle speed is 1000 r. p. m..
this is wrong, the TBI (why not post a photo of yours?, so we can see what generation you have)
im sure its a 1995 TBI , same as our. was.
the 2mm gap is dead wrong, for vitara's G16a in any country. .080" about 4 match book covers think gap, huge in terms of AIR.
that is my opinion. (keep in mind vast number of folks measure this and send me facts on theirs)
the side of the TBI has and air screw, see that the bleed this screw sets the idle not that stop screws or ever a 2mm gap. not at all.
i have like 5 TBI's in hand and see vast more and all are 100 (99.9%) closed, its open only that amount that prevents jamming or damaging the bore wall.
this is a fact.
what happens is this.
many owner, see idle too low, cold or hot. and then open that valve screw. this is wrong.
the bleed screw see set the duty cycle of the iSC to 50% (about 7vdc with meter) and that holds idle hot at 800 (TPS switch closed for sure) and we can put
any load on alternator or even select drive and rpm holds at 800 (a/c off and p/s not overloaded)



there are some key things that must be right to get the wet TBI to run right, the TBI is wet like a carb, was. and is dirty EFI TBI and is why it banned here.
it's the most bad cold. MPI was the cure here, and now, world wide.
the crude factory cure are high idle speeds at times, when cold, to prevent gas puddling in the plenum and runners. IT'S A WET MANIFOLD.

hot idle issues.
ok if at 180f or even 195f like mine
the IAC is roasting hot. its 100% closed, now, if actually hot, some are not, those paths do get blocked on many old car like that.
the ISC has 2 water lines too (electric valve ,modulated but the these 2 water hoses are to heat the TBI no the ISC, (it dont care)
so you have almost 3 sources of heat to the TB, one is the base water feed in base of TB.
so as you can see TBI heat is huge thing here, the A/t trans has heater screen below the TB< for a 4th heating source. (never leaned why a/t is bad. ok my brain just got it, the a/t might run low RPMs in drive and puddle more? unlike clutch car with clutch pressed in at stop signs....)

now the 800/1000 rpm thing driving , my assessments
if the A/C cuts on, the ECU sees that and goes to 1000 RPM , per the book. (called the fast idle pin on ecu. GOT A/C? (it's still hot here...)
the P/s overload switch wire can fail, (ground out) and 1000 RPM happens. 200 +800 = 1000 per software in ECU>
so can sticky throttle cables, up to 3 cables with cruise and a/t (yours is my guess 1cable car, )
next is that 2mm gap, that be wrong. (assessments....)
that is going to force the engine tuneup guy to closed the bleed screw 100 % this is wrong. and then the iSC can not slow engine enough
so when real hot engine , lots of extra power, and that huge 2mm leak of air, the ISC THEN DROPS REGULATION
this EFFECT is called, going outside the command authority of the ISC< (or, as I say, gee, the ISC is closed 100% now , how in the world can it close more that 100%, it can't)
so rpm rises.. it must, during this calamity.

The FSM book does not cover that TV secret GAP, they assume the screw is never touched, and that if touched you buy a new TBI, but they dont sell them now. (funny that, huh, but some makers of cars do spec this, and read them and they all say, .0005 to .001" )
so we measure that gaps, and its NEAR zero.
ive set many that were molested to .0005 (the smallest feeler i own) 0.01 millimeters (those zero's are real)

then i put my scope on the iSC pins of the hot engine. (ir gunned to be sure its really hot, or drive 20 miles)
and sit the duty to 50% , 1/2 high , 1/2 low , if not having scope, i set it to 7vdc, (14v high 50% is 7vdc if your meter likes you, some don't)
I then turn the bleed screw (hot) to 50%. duty, and hark 800 happens and is very hard to make it fail, unless I overload the engine. (dumping clutch will)
now the ISC can do its job under all conditions, of engine friction, efficiency or alternator loads, or fast idle pin demand)
to open 50% or close 50% and handle any load changes on the Alternator, or engine gets hotter and more loose. or the p/s or a/c demands 200 more rpm.

more?????,.............


DP actions
the top left screw here if unscrewed will lower the DP fast idle speeds, if you dont like the DP actions. ive avoided this, so as not to fool my ECU too much.

http://www.fixkick.com/fresh-air/no-touch.jpg

off my fresh air page....

Step 2: (8v only all years) FSM quotes.
THE DASH POT or DP: (aka; cold start fast idle servo diaphragm) CSV ?

If you must adjust the Dash pot, here is how: ( always done last #3) }{best practice is leave it alone} (unless someone messed it up)
This is the Cold Start High Idle, controlled by ECU. (operates for 2 to 30 seconds startup. and retracts.)

See spring loaded screws that touches DP?
Warm engine, set normal idle to 800 RPM first. (no tach 2wd? connect or Point an RPM gun to crank pulley [any kind])
With hot engine, turn off all accessories, A/C fans, lights, radios, etc. (P/S not in overload)
With engine running at 800 RPM , pull the DashPot vac. hose (plug it) this will cause the spring inside to raise the idle.
Set the RPM to 2100-2300 RPM by adjusting the spring loaded screw. On throttle shaft , rear. Called fast idle set below photos.
Undo all the above.

Some people don't like this idle speed and choose lower. I think that is OK. (if not to extremes)
Some even defeat the whole DP (unbolted) , letting the IAC do all the work. (makes cold starts rich and fools the ECU big time) flooding etc.

end fsm and commentary.

SENSORS:
yes, the car has 4 temperatures sensors.
1: dash gauge, (useless to EFI )
2: ECT
3: IAT
4: a/c overheat trip.
up to. #4 is missing if no A/c
2 and 3 are very critical sensors . and IAT too on all 8v , all TBI need an accurate IAT to calc, air density)

rule one, all EFI systems!
try not to fool it. or it can be a long hard day.

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if worried about cold start rpm's
run thinner oil in winter
or get a block heater (or mag attached pan heater)
lower the DP screw just a tiny bet, not whole hog unscrewed.
or crank engine if parked for a month , with the "FI" fuse pulled. cranking to prime the head oil gallery. (top end oiling) mine does 55psi just cranking...no spark.

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sure wish i know what rubber flapper is.... very curious....

Well, i'm still in the first message so I'm considering about thermstat also as you told me. Since some days ago I'm thinking about it because I saw on rhino manual thai it has a hole and if it is blocked become a problem, and also maybe gasket is in not good condition or as you say pipes clogged.. Before and in winter time, when the engine starts and during 400 meters the neddle from dash gauge barely move up from down side, but from about one kilometer more neddle was almost in the middle more o less of dash gauge, but now knowing that there is not could the neddle need only 100 meters to go up to the same place, but I saw it's two milimeters more down than before, althought is a toy as you say also..
Then I put a new radiator cap a month ago also but I don't found to purge air from system, maybe don't have is only through radiator cap, or not ?

But because the engine never overheatd I forget this system, and also because when the engine is hot and the idle is normalzed 800 r.p.m the engine working very well, when stop in traffic light or traffic jam, bu perhaps you are right, the problem could be that water temperature is under 180f or 82º Celcius.. The device IR gun is a good idea too to measure temperature, I'm going to open thermostat and see how is it, and if need I place a new one, anyway after 20 years is time to replace..

Yes TV is all the time closed 100% when cold and hot and resting in that Factory sealed screw, but only is open thouse two milimeters when I start in hot and DP retract, in this exact moment (I'll try send you photo) is separate from that screw as if was blocked for something when I'm trying to close it by hand, but if I accelerate pedal or by hand in TV I accelerate only a little it come down and don't make this more just when starting in hot first time again..

And about bleed air screw in TBI has as you say is about two milimeters gap before stop in the end..

I thought to buy a new Suzuki car with MPI system but this vitara is still in right conditions, the engine compression is OK power is as if was new, I have taken good care of this car, timming chaine is replaced, change oil each 5000 kilometers, all filters, it never gave me serious problem, I changed cardan and oil seal in rear group by myself and something like this.. After put the new TBI I went to test it and to visit a friend to Madrid, Spain capital from my city, this mean about 1000 kilometers go and back, and other 1000 kilometers more to visit other city, and any problem about for the contrary I was surprised how still is working as if was new, including A/C system that goes to 1000 r.p.m when stop in idle, the only problem is when start in cold or hot, so I decided to find it..

Yes, TBI in this model is dirty, when I removed the IAT when the engine was hot it was very dirty like black liquid and I thougth what is this inside the intake manifold? I think was gasoline..

So the two hoses lines is not to heat the ISC but to heat TBI ? I believe to heat ISC, but you are right has non sense to heat ISC..

About sealed screws in Factry DP lower and high I don't going to touch them neither other like these as hex 5 milimeters in ISC solenoide valve or TPS screws sealed too..
Yes this model has 4 sensors all are new less number 4 overheat trip because A/C working very well as you know now..

The rubber valve is inside the IAC you can touch it if you open this termal wax opening the three screwus under the ISC valve in this model but if I can send some pictures you can see all about..

Well, now I'm going to read your athers message and maybe tomorrow I'll reply you again.. Greetings and thanks..

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Hi, I went to Gallery as you said me and I have been able to sent two photos about rubber valve you can see it in black color when IAC termal was open..
I'm going to send you the entire valve when I opened with a grinding machine to see much better a month ago, similar like you opened an ISC valve too..
And other photo is my TBI with ISC and hex 5 milimeters sealed in Factory with silicone..

I'll send some photos about..