heat soak issue and wont refire until completely cool
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heat soak issue and wont refire until completely cool
Hi all, after much work all the ign system has been replaced thinking it was a coil or distributor.....still wont refire after hot drive. Then let it cool for 4 hours it refires like it should. If you crank the car it acts like has no fuel or spark and wont start at all. I have a fuel pressure gauge hooked up and it shows 45 psi all the time wether hot or cold so i want to say vapor lock or boiling fuel is not a issue.....how can i check the injectors to see if the injectors are getting heat soak?...without pulling the intake apart
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__________________ High rev'n TPI......wait oxymoron?
CURRENT--1991 trans am--333ci TPI/700r4 :P--
PARTING--1985 TRANS AM--LG4/700r4--full bolt ons--
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Re: heat soak issue and wont refire until completely cool
have you replaced the ign. module? i've seen several cars that when they were hot the ign. module would stop working until they cooled down. also if there wasn't enough grease under the module.
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by Toyota h8r
how can i check the injectors to see if the injectors are getting heat soak?...without pulling the intake apart
Pull the injector connectors and using an ohmeter check each injector. You should be in the 14-16 ohm range. Doing it with the engine hot is the best way but if you're problem is being caused by the injectors, you'll notice the problem with them cold.
Re: heat soak issue and wont refire until completely cool
im running used LT1 injectors and according to LT1 owners stock 24#'s ohm at 11-13 ohms....mine all test from 12.3-12.5 last time i checked
like i staed before also....EVERYTHING ign related has been replaced
--ign module
--pick up coil
--cap/rotor/wires/plugs
--ign coil
i have hedman longtubes and the are clost to the lines on the driverside but im still reading the same FUEL PSI cold OR hot
im wondering if the injectors are heating up and shorting out and causing the other intectors not to fire. If you drive car for 5-10 minutes car will refire...but drive for 20-30 minutes or beat on car it wont refire for 3-4 HOURS!!!!!!!!!
im really close to just torching the car....evil car
Re: heat soak issue and wont refire until completely cool
okay im about to burn this car down lol......went and drove car...well beat the piss out of it so it would get nice and warm. Pulled in garage and let sit for 15 minutes. Turned key and wouldnt fire up at all.....NOTHING!
so i grabbed my handy multi-tester and ohm'd out every injector only to find exactly the same ohm rating as when the injectors are cold! WTF??????
im lost...i even tried unplugging the MAP sensor...didnt do anything different(try to make car rich)
i tried unplugging the coolant plugs(heard about computer glitch and being too lean on hot start...didnt do anything.....
ok...ive got spark and 45psi of fuel pressure......im 99% sure its got to be fuel injector death or computer is being ghey
ALSO, when car does run and drive it is retardly slow and has no power at all......im talking mid 15 seond 1/4 times slow aka embaressed to own slow
im not sure if knock sensor is pulling timing or what....this damn car is slow as balls
short mod list:
327 bored to 333ci(zero decked block)
forged flat top pistons(-5.3cc dome)
pink rods
1103 summit cam(214/224 .442/.465 at 112LSA
stock 083 iron heads
stock tpi intake setup
3300 stall...big but motor loved it BEFORE TPI
700r4...with shift kit
3.23 gear set
im wondering ig the 350 knock sensor in my 327 is acting up and with 10.1:1 compression its pulling timing...it feels dead all though the power band.
Re: heat soak issue and wont refire until completely cool
Had a crazy issue with my dad's GN last year. Very similar symptoms as bad injectors. Turns out a new battery fixed the issue. Apparently it had a cracked plate internally.
Re: heat soak issue and wont refire until completely cool
I had the exact same problem once with my car......and it turned out to be fuel pump. Same thing though....I checked it with pressure gauge and it said 40+ psi, so I thought that couldn't be it but what happened is it was vapor locking...getting air in line...next time it does it....try bleeding fuel line at schrader valve...see if air bubbles in fuel line.....
__________________ "Wide open 'till you see GOD, then brake!!"
'91 Camaro RS B4C Police Special Service Package
350 4-bolt, 10:0 w/moly rings, Holley Stealth Ram (ported), BBK 58mm, MSD ignition, Procomp heads 2.02 1.60 200cc (63hrs. port work), 30# venom injectors, Flowtech headers, full custom 3.5" mandrell ceramic exhaust w/ aerochamber, Comp cam XFI280HR (.576/.571 234/244), PCMforLESS.com tune, 58mm BBK, Custom TPI air lid, Custom RamAir, 1.6 stainless steel rollers, Custom 700-r4 2500 stall, Aluminum Drive line, 3.23 posi, Moser axles w/stud girdle cover, Spring works springs (lowered), UMI relocation brackets, panhard, LCAs, sub-frame connector, boxed A-arms, Poly bushings, Custom interior, Powdercoated & polished IROC wheels, Custom "Black Cherry" Paint", 4pt. roll bar, +++ more! "It's not the tires squealing, it the asphault SCREAMING!!"
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by 91interceptorZ
I had the exact same problem once with my car......and it turned out to be fuel pump. Same thing though....I checked it with pressure gauge and it said 40+ psi, so I thought that couldn't be it but what happened is it was vapor locking...getting air in line...next time it does it....try bleeding fuel line at schrader valve...see if air bubbles in fuel line.....
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by 91interceptorZ
I had the exact same problem once with my car......and it turned out to be fuel pump. Same thing though....I checked it with pressure gauge and it said 40+ psi, so I thought that couldn't be it but what happened is it was vapor locking...getting air in line...next time it does it....try bleeding fuel line at schrader valve...see if air bubbles in fuel line.....
i would try the schrader thing but i have my electric fuel pressure sending unit there and cant easily pull it off.....
oh and heads up......it has brand new pump....i have thought vapor lock also might be issue
im saving up for a ls swap.......im tired of this garbage...ive spent so much money trying to get this car just to be reliable
Re: heat soak issue and wont refire until completely cool
okay...this one might put you guys in a tail spin mentally lol
i drove car to friends house and sure enough 15 minutes go by and crank...crank...crank...NOTHING!
it turns over the same as cold...
i hook my laptop up and while i crank car the injector pulse from the computer isnt doing jack crap....
so buddy comes up with an idea.....unhook battery cable and reset the comuputer....at first it didnt work so i unhooked it for 6 minutes
i also heard about hard starting hot with tpi cars so before i hooked the battery up i disconnected the CTS on the front of the intake. I hooked the battery back up and VROOM! the retarded car fried up and just like it does cold.
So people that have hard or no start hot like heat soak unhook the battery and the CTS for 6 minutes or more....then hook back up and should fire up....
Re: heat soak issue and wont refire until completely cool
That's exactly what my dad's GN did with the battery "trick". Do you have a different one that you could swap in? Even new batteries could be bad......
Re: heat soak issue and wont refire until completely cool
im so close on just giving up on this thing......one thing to try is the 3 wire o2 sensor trick and maybe the whole 1 wire and long tube issue is killing my car and running stupid lean like ive heard here on TGO
Re: heat soak issue and wont refire until completely cool
okay after install of 3 wire bosch i learned car is running rich.....very rich
like 11.4 at WOT rich lol
a friend came over and added some spark advance and tried figuring out the hot start issue only to be dumbfounded like me lol.
i am seriously lost about why it wont refire hot....unplug teh CTS and 9 out of 10 times it will refire. My friend added fuel in the hot start table(coolant temp vs injector pulse width) and didnt help
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by 89-bird
Which of the three CTS's are you unpluging you have one for the fan/s , one for the gauge , and one for the computer ?
the one on the front of the intake...the computer one.
this in turn tricks computer into thinking the motor is cold and thus enriching the fuel ratio. It doesnt work everytime but it helps out.
im going to have to swap injectors it seems.....ohm'd them out and they spec out to 12.3-12.8 and are LT1 spec but i suspect they arent firing correctly hot.
motor is running great and actually rich under WOT.....like 11.6 rich LOL
__________________ High rev'n TPI......wait oxymoron?
CURRENT--1991 trans am--333ci TPI/700r4 :P--
PARTING--1985 TRANS AM--LG4/700r4--full bolt ons--
Re: heat soak issue and wont refire until completely cool
Yeah I would try stock injectors for your engine and see how that does you may be getting to much fuel to your engine with those LT1 injectors to cause the rich WOT .
__________________ Mighty 2.8 power . Enough said .
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by 89-bird
Yeah I would try stock injectors for your engine and see how that does you may be getting to much fuel to your engine with those LT1 injectors to cause the rich WOT .
well the computer has a basic tune....im wondering if i do need to go back to 22 lb setup......im going to a HSR soon and better heads
so i need to plan accordingly......whats 22lbs good to hp wise?
__________________ High rev'n TPI......wait oxymoron?
CURRENT--1991 trans am--333ci TPI/700r4 :P--
PARTING--1985 TRANS AM--LG4/700r4--full bolt ons--
Re: heat soak issue and wont refire until completely cool
From the link the only thing I can see is they both run a 4 pattern spray . The Bosch lll may be a 22 lb instead of a 24 lb . And the 24 lb injectors are cheaper .
__________________ Mighty 2.8 power . Enough said .
Re: heat soak issue and wont refire until completely cool
what computer is in that car adn what tune are you running? Has it been tuned for that 327?
If not thats the problem. Hard Hot restart is because your getting too much fuel on startup. Coolant temps are up, and startup enrichment is spraying too much fuel. this happend to me on my 383 and i was running stock startup tables.
Leaned it out and its firing hot everytime easily.
I would think you just need to tune that car abit more
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by Orr89RocZ
what computer is in that car adn what tune are you running? Has it been tuned for that 327?
If not thats the problem. Hard Hot restart is because your getting too much fuel on startup. Coolant temps are up, and startup enrichment is spraying too much fuel. this happend to me on my 383 and i was running stock startup tables.
Leaned it out and its firing hot everytime easily.
I would think you just need to tune that car abit more
its a 7730 ecm with a moates.net adapter and flash style chip.
it has been tuned for the 5.3L and 24# injectors. Thing is the car isnt spraying fuel when hot and will fire on carb cleaner for a sec and die out due to no fuel. Its weird due to o2 sensor under WOT is showing rich condition and 14.73 under light cruise. BUT, test them with 12 volts when they sit and soak heat for 15 or more minute with car shut off.....they dont fire. When the car is running they click pretty good.
__________________ High rev'n TPI......wait oxymoron?
CURRENT--1991 trans am--333ci TPI/700r4 :P--
PARTING--1985 TRANS AM--LG4/700r4--full bolt ons--
Re: heat soak issue and wont refire until completely cool
i dont have a wideband yet but im stuck on what one to get. Im looking at inovative products basic digital one. AEM and such are really pricey and have a lot of things i dont need.
i couldnt really do any good pulls today due to semi slick roads. Seems to run better and now the idle is better. Found out the HVAC/cruise vacuum line wasnt sealing on the plenum nipple and was a vacuum leak lol. So i capped it off until further notice and runs and idles better lol.
only thing that sucks is finding a place to mount the wideband o2 sensor.....i have longtube headers and im "borrowing" from a fiend. lol figure that out.
the car is sluggish when the gas is stomped and under partial load it drives better(more advance from computer...wtf?)
partial throttle = 35 degrees
WOT before = 29.9 degrees
WOT now 31* degrees
i want to jack the timing up to 34-35 degress. Due to me having 9.9:1 compression and decent cam i have been running sunoco 94 ultra and car seems to run better on this than lower grades
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by Toyota h8r
i need to have friend tune it a lot more.......
We'll see how things shake out this weekend, but like we discussed, I'll throw more timing at it if you like. Or you can drop a chip off, I'll burn it, and you can pick it up. I'll either add more timing in the base map, or I can put more in the PE spark table. I just wanted to be cautious because burning a new tune is free, buying new pistons is not.
Also, we gotta get this hot start issue fixed so you can drive the car.
To whoever suggested pulling hot start injector pulsewidth.... I know exactly what you are talking about. My 383 did the same thing, and when you opened the throttle up it would finally start. So I leaned it out and its perfect now. Shelby's car won't even try to fire no matter what you do and it does not smell rich while trying to start. I know it doesnt make sense, but it really seems like it's just not getting fuel on a hot start....
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by 1MeanZ
Also, we gotta get this hot start issue fixed so you can drive the car.
To whoever suggested pulling hot start injector pulsewidth.... I know exactly what you are talking about. My 383 did the same thing, and when you opened the throttle up it would finally start. So I leaned it out and its perfect now. Shelby's car won't even try to fire no matter what you do and it does not smell rich while trying to start. I know it doesnt make sense, but it really seems like it's just not getting fuel on a hot start....
So no fuel on a hot restart. Look at the MAT vs. Crank Fuel Delay table. If the MAT is above X it actually keeps the injectors from firing ANY fuel until Y number of ignition reference pulses pass. You might play with the values in this table along with the Cranking Pulse width. I know the 383 Vortec in my Van would not fire HOT on the stock AUJP Tuning.
Re: heat soak issue and wont refire until completely cool
Quote:
Originally Posted by 1MeanZ
He has has MAT sensor out beside his air filter. I'll pull up his .bin and see whats up....
truth
im hoping new injectors and maybe something tune wise is what will unlock the car's power. car just doesnt have any power.....like the computer is holding back
Re: heat soak issue and wont refire until completely cool
well....id figured id let people know whats gone on last few days.
UPDATE!
after being mad at car for so long a friend conviced me to work on the car and i tore the intake all apart down to the lower base nothing left lol. I replaced all the tpi gaskets and used rtv to help seal them this time. I also put the SouthBay Fuel injectors in(24# Ford racing ones).
Let the rtv dry and fired the car up...HOLY Y*(UH the cars intake sounds like a pissed off vacuum cleaner So i know i had a stupid bad leak lol. It idled right down to 500rpm and now the iac is showing itself to be bad(sticks). The runs like a bat out of hell now but i have murdered the poor 700r4's 2nd gear
ONLY bad thing now theh tune is screwed up now due to car is ruuning right and is uber rich on restarts and having to press petal to the floor to fire is annoying lol. BUT IT FIRES EVERY DAMN TIME NOW!!!!!!!!!!!!!!!!!!!!!!!
NOW its time to figure out what to do about a trans lol.....im thinking t56 due to the lt1 sitting on my garage floor i just bought for 300 bux muahahahaha
"It's not the tires squealing, it the asphault SCREAMING!!" 
