91 8V hard start long cranking on hot soak. cold great

[barnbiketom]

it must be inspected, blocking the MAP , will cause limphone, instantly.
the map is easy to test. first for leaks then volts, i have a map test page.
but its working, im sure, only hose leaks are at issue on it.


this is easy to find, you have all air shut off, and it runs
that impossible or you have leaks, yes you, do....
where? we just block holes and find it , id bet one of those 2 holes in the TB leak, no?
if all gaskets are good. and the brake booster dont leak , where else is there, non?
the engine must no run with all air cut.

if the tb tests fail, then we only need to find the internal part that is bad,

you have a huge air leak.

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I took off the snorkel to air filter..held my hand over the aluminum tbi cover extension.
Motor stalls instantly.. Im quitting for now.tired and cold hehe.. Next week im off monday and tuesday...grrrrrrr

Thanks so much for guidance...

[barnbiketom]

forget to mention, it looks like PO had screwed with the adjustment on the electric ISC hex in the front. I played with it but at that point i was too tired and quit..

"the allen wrench is never used , unless the ISC set starts to leak too much. set it so the ISC pistion seal just barely touches seat if you dont want to buy a new $200 ISC"
I know this isn't the main cause since I can pinch off the inlet hose.. no change, but I'm going to take it all back apart next week and really look at things again!!!

[fixkick]

you are getting close. nice trick the snorkel block,(way cool), id be afraid it suck my old skin off, LOL
ok so that proves the leak is inside the TB. very good.!!!!
we can retune the ISC later ,

ok, this one is fun, not just a simple leak. but we will find it, , it's in the TB somewhere, or those 5 holes on the bottom (drillings) are not blocked.
correct isc is not main culprit,
pulling for you.
good night, !

[fixkick]

i'd want to know which path inside the TB is leaking. air.?
blocking ports finds this, bottom side, finds it the most fast.
its not ISC nor IAC, they are closed, so there must be TB Damage inside,?
i dont have a real xray view of the TB, just that nice but physically inaccurate one from from SUZ. below.
see exit port below just to left of red idle air;
that is the big 3.8" hole, blocking that hole, id bet ends the leak.
water hole, checked,
5 drilling holes ,tiny blocked, with stock gaskets.
3/8" is ISC and bleed and iac outputs.
slot hole. this is ported vacuum to EGR and dash pot ,via vsv valves. the valves are closed at idle and no air can pass, so... cant leak to the slot.
this slot is ported vacuum, EGr has no vacuum until off IdLE AND DASH POT IS hard vacuum all time (evap and map have dedicated manifold nipples)

im sure the slot HOLE path is not failing, but did you pinch the dash pot and egr lines to see if they cause idle drops at idle.
the dash pot might extend doing that and raise idle.
but not drop idle rpm. pinched.

id bet the 3/8 inch hole leaks air. big time. why ,will take careful checks with blowing with mouth on it and listening with rubber hose to ear, moving end of
hose all over to find this hiss of your breath. "escape path"

its not the fuel pressure reg leakings vacuum its on the atmosphere side if TV



here

[barnbiketom]

"did you pinch the dash pot and egr lines to see if they cause idle drops at idle."
yes I have pinched off all hoses..
I actually have several HOSE PINCH plieers left over from my pontiac/ford/mercury/subaru dealership days.
I hate vacuum leeks hahaha
The gasket set i used was a 'standard' just like in your page. and the 5 holes were blocked, but on monday
I am ripping this apart again
lately too the car stinks again and gas mileage is bad but I am actually checking for NUMBER this time after fill up.

LAST NIGHT I had to go out and the car was idling at 1000 or slightly LESS??? wonder why? seemed like no start up flare..
I'm going to back out the TV screw in case the PO turned it.. it is HARD TO TELL.. but white paint on it.. but ?? did he turn it?
it looks CLOSED from the top but...
maybe throttle shaft is worn? car has 150, 000 miles. but propane check no change in ide anywhere hahaha

I am going to check the coolant and intake air sensor soon today, cold, for values..i forgot to check them cold.
they should be same cold correct??
it is 33 F here

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The car sits out, but I have a 40x60 shop for working on cars haha..
33 F degrees out
coolant sensor: 6450 ohms
Intake temp sensor: 6080 ohms.

my temperature. COLD ha
I had hardly any fast idle, after dashpot pulled...so I used allen wrench and turned out allen screw on thermal valve 1 1/2 turns Idle went back up to 1500 cold .. now later I got to work and see what happens..

[fixkick]

yes, nature hate a vacuum(on earth) and for sure all mechanics hate finding them, some leave you missing all hair.
yes, 33f both read same parked over night, both ECT and IAT. near. 6000 ohms = 32f
they equalize parked while you sleep; and is a great test before starting any car. with eFI.

there is a huge vacuum leak inside the TB FOR SURE. why only takes blocking that huge hole, ahh, it stalls now and wont start, easy..... yes...
blocking that hole is the hard core proof this path leaks. very bad, so bad engine can run, and must not (IAC ,ISC AND BLEED CLOSED)
AIR LEAKS ONLY Cause tiny increase in mph, 800 normal , faster wastes most fuel but not by much.,
low mpg is other problems....
low mpg , sounds to me like ,
1: FUEL PRESSURE too HIGH (all reasons)?
2: STUCK IN LIMPHOME(FAILSAFE ORBACKUP) OR O2 SENSOR STUCK AT 0VOLTS
3: leaking injector, no its not you looked.
4: bad ECU,? say needs new caps, as all do, 1 time ! ID never run any ecu with Rubycon caps ever, i run nichicon. (real japan made top brand)
5: ON THE 8V IT HAS THE NASTY RARE FAILURE, IN THAT Only (caps key bad) in that, the one side of the dual driver is shorted.

the 2 injector wires are driven, and if one shorts, the fueling is all wrong. I find this easy by doing all 3 noid test in my injector page.

transverse test
and hot driver to ground
and battery to lamp and ground driver .
all must flash cranked, or that driver is bad, if any show the lamp stuck on, that driver is bad. both lines pulse, i have scope views on both.

just doing a text book transverse test, fools you in to thinking both work.

8v has tricky injection system. unlike 8v that is very traditional.

transverse test 1: (ascii art?)
injector pin1 >>>> noid>>>>> injector pin2
hot line red pin: >>>>>> noid>>>> engine ground.
gnd line yell pin >>>>>noid>>>> 5amp fuse >>>> battery +

noid is noid test lamp. I use a $1 lamp.

and for sure scope works far better.



scope 101: 8v injector, running engine.
not stuck low! if yes, the transistor is shorted. !
http://www.fixkick.com/INJECTORS/INJ-yel-to-gnd-w1.jpg

not stuck high or low. HOT side)
http://www.fixkick.com/INJECTORS/INJ-red-gnd-1w.jpg

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good luck,!

[barnbiketom]

I've not checked the fuel pressure.. I see you do it at the filter and YES I HAVE HARBOR FRIGHT EFI kit!

I DID PULL OFF THE regulator return line while it was running with bottle and rags ready..let it Burn haha.. oops..
there was a flow of
fuel from it at idle.. a full pipe full but not much pressure or volume. sound ok?
I'll do the noid test too. i have some noids. but need to read your test. all i know is it runs hahah.. runs fine but stinkey too. no driveability problems.. no codes but 12,12,12
BUT I THINK ABOUT THOSE CAPS all the time under the dash haha. who knows? not me. never looked

[fixkick]

yes, 8v must be done at the 6mm filter banjo bolt
the car has fpreg that love to fail this old, on this car, it works by altitude only !

flow tests are hard, all that matters is spec pressure at all engine loads! the return line runs all the time,...
and the diaphragm is not cracked, leak down test on it, with any vacuum hand pump or 30 seconds.
the fuel pressure must hold steadyat idle and gunning the throttle (not true 16v)
the FSM tests are lacking,. I use hand vacuum tool at vac, nipple on FPreg to run it from min to max. 8psi range. fsm skips this test..oddly...
but there is key on pressure, and running.,test,
day1:
1: caps not stock. checked,
2: crank pulley at 94 ft/lbs.
3: fuel pressure at spec, the FPreg loves to (this old) crack its diaphragm , or inside gets grooved and sticks,) .

runs good but all cars do even with AFR stuck at 12:1 rich, and make more power rich. in fact that is what WOT does. same.
but at idle that will stink running. and cat will run hot there.
12:1 is too rich. and means that the 02 closed loop is failing. badly. 14.7:1 is normal hot idle AFR and will not stink, 14.7:1 is all fuel burnt
every drop, and just a little oxygine left and lots of CO2.

[barnbiketom]

NEWS FLASH
[size=medium]
I was going to test fuel pressure.. was going to "TEE" in a schrader hose. but upon testing the diaphram.. it LEEKS..

also when running, the diaphram port has gas spitting.
I got one at local part store for $2 more than rock auto..JOY!!

old car= maybe more than ONE problem..???? hehehehe

[barnbiketom]

NEWS FLASH NUMBER TWO CAR FIXED ALL IS WELL

I replaced the FPR.. no more long cranking after hot soak.. the vacuum line was dribbling
all residual pressure into intake manifold,

CAR NOW IDLES AT 800....+-
when I turn on AC idle bumps up.. ISC working.

I RE CHECKD THE TV.. it was either disturbed or WORN?? (i have bad eyes anyway.)

I had to turn the little screw OUT almost TWO FULL TURNS before it BARELY WAS ALMOST CLOSE TO BEING CLOSED (hard to explain) .250 between measuring too..also..good test!!

SO SORRY i didn't see this when I had it off first time, the white paint 'looked' ok but must not..

my motto is : "it's always something EASY.. you just gotta find it!!!!!!"
Hats off to Fixkick for getting me to head in right direction even tho it took me TWO TRIES . HAPPY Holidays.. even tho you are way south. I'm jealous.. no snow???? hahha