What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

what the heck does batch fired mean ??

R

R72K5

Banned
Joined
Mar 5, 2001
Posts
8,905
Reaction score
0
Location
central IL
what does batch fired mean ??

1992 vin code Z 4.3L engine with TBI

these engines are batch fired

how does this system work?

what tells the injectors to fire ? where does info come from ? i have been told in the past that the distributor fires them

does it ?

thanks /forums/images/graemlins/hack.gif
 
i believe batch fired means both injectors fire at once, and I believe they are controlled by distributor, but computer will of course change the amount, or it can interupt it, incase of no oil pressure, etc.
 
hum

ive noticed in the past that both injectors fire when cranking, running, but then thats what ive always noticed with TBI engines,

so thats nothing new,

it jhas to be like that anyways, for both banks of the engine

so hmm

if a TBI engine is not batch fired then what else could it possibly be ??

apparently its just a name and doesnt mean crap, just means both injectors fire, in which is has to do anyways


i guess theres nothing more to it than that

i do need to learn what makes them fire though

if its the distributor then how doew it work ?

where can i go read/learn how this works ?

and find out if theres a crank trigger sensor on these and how it is involved on this type of injection ?

maybe then i could trouble shoot this damn truck and figure out why in the hell it wont start half the time


thanks
 
There is no crank sensor. I think it uses the ignition module, and when the module senses spark, it fires injectors, and then the computer takes into account engine temp, O2 sensor, and adjusts the amount of fuel injected.
 
[ QUOTE ]
There is no crank sensor. I think it uses the ignition module, and when the module senses spark, it fires injectors, and then the computer takes into account engine temp, O2 sensor, and adjusts the amount of fuel injected.

[/ QUOTE ]

hmm ok,

an ignition module exists for TBI systems ??
like same as for carb HEI engines ??

would faulty module cause no fuel injection during cranking ?
what else could cause this problem ?

thanks
 
[ QUOTE ]
There is no crankshaft trigger on a TBI engine.

[/ QUOTE ]

ok then i am thinking of MPFI systems then

my bad

hmm then what other components could cause no fuel spray then ? other than the ECM ?

o2 ? TPS ? neither ?

temp sender ?
oil sender ?
but if was oil sender then why would it run fine after you get it started with starting fluid ?

im at a loss



thanks
 
I dont know about carb HEI, im not learned in those, all i know are tbi, and in a semi turkey coma, i think I am thinking clearly.

I had a bad ign module, and it caused some freaky weird problems, no start, random shutoff, etc. Then I also had a temp sensor go bad, and it cut fuel to the injectors. Something you could do is, pick up a NOID light, and plug it into the injector harness (unplug from injector, and plug into light). If light fires, then the module is working, and the injectors should be firing, something else is keeping them from firing. If no light, then their not getting the impulse to fire, and I would look into the module.

If they are gettin an impulse, just not fuel, those are same symptoms i had when my temp sensor (in the manifold, not the head) went bad.



I just saw your reference to starter fluid, when my temp sensor was gettin sticky, i could get it to fire on starter fluid, and it would run fine, then one day, even that quit workin, and it would just run off the starter fluid, then die.
 
[ QUOTE ]
I dont know about carb HEI, im not learned in those, all i know are tbi, and in a semi turkey coma, i think I am thinking clearly.

I had a bad ign module, and it caused some freaky weird problems, no start, random shutoff, etc. Then I also had a temp sensor go bad, and it cut fuel to the injectors. Something you could do is, pick up a NOID light, and plug it into the injector harness (unplug from injector, and plug into light). If light fires, then the module is working, and the injectors should be firing, something else is keeping them from firing. If no light, then their not getting the impulse to fire, and I would look into the module.

If they are gettin an impulse, just not fuel, those are same symptoms i had when my temp sensor (in the manifold, not the head) went bad.



I just saw your reference to starter fluid, when my temp sensor was gettin sticky, i could get it to fire on starter fluid, and it would run fine, then one day, even that quit workin, and it would just run off the starter fluid, then die.

[/ QUOTE ]


hum well its apparent that no voltage is going to injectors since it wont fire them at cranking speed

thats th whole problem here

something that makes the injectors fire for cranking is whats wrong here

what is a noid light ? i have heard of that before, never seen one i dont think

i have a little digital multitester,

would that do me any good ?

if so then what setting to test for voltage at injector wires ? and which ones are hot ? the red or blue ??

so bad ign module definitely can cause no injection during cranking but fine during running or ?


and temp sensor, hmm..

with the dash guages all screwy how can i know if the temp sensor is faulty or not ??


cant afford to replace temp sensor and ign module, its just not worth it, although new temp sensor may fix the gages light problem, hmmm

but i dont remember any problems with temp guage before the light started coming on, but then thats what the light is for is to tell you to check gages, which i would think also includes sending units

hmm

what else ?

thanks!
 
Randy, i had a very similar problem with my 93 C1500. it was an intermittent thing, once in a while it would fire up and drive fine. 2 miles down the road, you're stuck again. ended up being the ignition module.
 
well, theres 2 temp sensors, one in the head runs the gauge, and one in the manifold runs the computer.
noid_%20lights.jpg
thats a noid light. Well, the computer reads the temp sensor, once it gets past a certain temp. Mine got stuck at 210* which is a temp where it is being read, and is a temp, where the mixture gets leaned out. Really, until you see if the injectors are getting an impulse to fire you cant narrow it down more. I think my noid light cost 5 bucks.
 
[ QUOTE ]
Randy, i had a very similar problem with my 93 C1500. it was an intermittent thing, once in a while it would fire up and drive fine. 2 miles down the road, you're stuck again. ended up being the ignition module.

[/ QUOTE ]

would it ever die on you while driving though ?

this one never does,

but on a real long trip it would cut out bog down for about ten seconds and then recover as if nothing happened

but it didnt always do it, but if it did then it would be just plain out of the blue as if the fuel system was shut off, then poof it comes back on

thanks
 
[ QUOTE ]
well, theres 2 temp sensors, one in the head runs the gauge, and one in the manifold runs the computer.
noid_%20lights.jpg
thats a noid light. Well, the computer reads the temp sensor, once it gets past a certain temp. Mine got stuck at 210* which is a temp where it is being read, and is a temp, where the mixture gets leaned out. Really, until you see if the injectors are getting an impulse to fire you cant narrow it down more. I think my noid light cost 5 bucks.

[/ QUOTE ]


wierd! never seen one of those before, that doesnt even look like a light hmm

how does that work ? it have an LED or something in it ??

and where am i gonna find one of those out here in corn field land ??

we have a small auto zone, a normal non-super wal mart, a small new o reilly's and an old small napa

am i screwed ?

two temp sending units ?


damn....

i think this truck is doomed

it runs and drives so good though, but just wont freaking ever start

i give up


i am fed up with it

i do not know what to do

its still a guessing game, we do not have the $ to play this game with this chevy piece of crap

what do i do ?

i am at a loss

i think TBI is one of or the worst system ever produced, other than CFI i guess


total crap


and i bet you if i go to all these stores that not anyone will have any clue what a noid light is, or ever heard of one


thanks
 
well i been havin a stupid moment lol, on a 350 it has 2 temp senders, i am unsure on the 4.3. I would assume it would have the same. I got my noid light, it was in one of those plastic bins up near the parts counter at autozone. (those little containers that have keychains, worthless screwdrivers, etc).

Those 2 little brass things are the prongs, that plug into the wiring harness. Then on the top (that is a diff design than the one i have) there is a little bulb in the plastic, and when u turn the key it should flash on and off, rapidly.
 
Batch firing means that 2 or more injectors are firing at the same time.The latest thing is sequential fuel injection (SFI). This means there is one injector for each cylinder and it only opens when that cylinder needs fuel.

Now for why your not getting fuel. The ignition module on TBI engines reports crank rotation information to the ECM that in turn tells the ignition coil to fire and opens the injectors. So if you have spark but no fuel your ignition module is fine.
Unplug the 2 injector and look for 12 volts on one side of each plug with the key in the run position. There are 2 fuses for the injectors. If there is 12 volts, then plug in the noid light or any other 12 volt digital tester and check for pulses when cranking. If there are no pulses start chasing down broken wires back to the ECM on the pulse wires.

Have you checked for fuel pressure?

Has the truck been sitting for a while?
If it has, you could have gummed-up injectors. The computer doesn't have enough current to open a gummed injector. The fix is to clip one side of the injector to ground and clip a wire to the other side and touch it to the + of the battery a couple of times quickly. Do not leave it connected to the battery or you will junk your injector. Just tap the wire on + a couple of times and you should hear the injector clicking. Do this to both injectors.

Hope this helps.
 
My friends 4.3 in a 94 2wd did the same thing for months--drove him nuts,had to carry starting fluid with him everywhere,finally it would not start even with ether--he tried a new fuel pump,sending unit(rotted to death!)coolant temp sensor,throttle position sensor,every time he changed something it seemed to cure it for a few days,then back to the same crap again.Another guy said it was the "5 second prime curcuit" for the fuel pump and injectors,we never figured out what he was talking about.Finally he broke down for the last time--he put new distributor module in it,and swore he'd scrap it if it acted up again--so far,its started every time,and even runs better than it ever did!--I guess its possible to still have spark,but lose the signal to the ECM for the injectors with this type of module--the module also does the spark advance too(no vacuum advance)so that part of it can go wacky too. /forums/images/graemlins/crazy.gif
 
First of all before replacing parts. CHECK FOR TROUBLE CODES!!!!
Let the ECM tell you whats wrong.
If all you get is a code 12 its prolly your ignition module.
If the ECM sees no spark(bad module) it shuts off the fuel to prevent floding.
Other things to check
Fuel pump and ECM fuses
Fuel pump relay
Fuel pump. Can you hear it running when you turn on the Key?
Coolant temp sensor.
 
I don't know if my info will help any cause its a 350, but mine would stall intermittently while driving and pop a breaker every now and then. then one day it just did not run at all. Well a friend of mine and I traced it down to the power wire going into the firewall. There was a burnt connection so I found an old one in a junk yard and all was well. It had all the same symptoms as yours. Its somewhere to start.
 
check the fuel pressure as mentioned before, I had the same problem wen my fuel pump went out. It started by sometimes stalling going around a corner with less than 1/4 tank of gas. If you can start it with starting fluid then you're getting spark but not enough fuel pressure for it to start. /forums/images/graemlins/woot.gif
 
You must log in or register to reply here.

Latest Posts

Top Bottom