EFI on L28E
08-05-2008, 05:11 PM
#1
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EFI on L28E
is the fuel injection all suposed to spray at the same time? because mine are.
i have good spark, REALLY good compression (new engine) and the injectors are spraying bearly any. i have the fuel rail off with the injectors hooked up and watching them spray. i dont see why its being so stuborn with running. timing is right on the dot also.
i have good spark, REALLY good compression (new engine) and the injectors are spraying bearly any. i have the fuel rail off with the injectors hooked up and watching them spray. i dont see why its being so stuborn with running. timing is right on the dot also.
08-05-2008, 08:07 PM
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does anyone have any idea why they wouldnt be firing good? they fire fine when we tested them but now there not firing good at all. the rail pressure is 30PSI, and the pump 50.
08-06-2008, 12:45 AM
#6
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just cleaned them and they all squirt fine. got voltage going to them because there working. and the connections are good. i dont know how much volts it has tho? its somthing to effect all of them at once because i dont think all 6 injectors went bad. the car sat for a year or so.
08-06-2008, 06:21 AM
#8
If they are spraying, and it's got clean fuel... the injectors aren't likely the prob.
You say it's not running well? When did that start? Was it running fine before? What were you doing when it started running crappy?
You say it's not running well? When did that start? Was it running fine before? What were you doing when it started running crappy?
08-06-2008, 09:24 AM
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hahahaha, i would have never guessed that one bleach. =P
nah, i bought the car and it would run fine with ether or if you sprayed
fuel in the intake which told me right away it was a fuel delivery problem. the injectors are spraying on 12 volts, not sure what the voltage was because we used a test light as a resistor to drop the volts down to 9 or so and they all spray fine and took the DMM and tested them and there all good besides one show's a funky reading and makes the meter bounce around but it still sprays. but when there connected it sprays very little.. if not none.
nah, i bought the car and it would run fine with ether or if you sprayed
fuel in the intake which told me right away it was a fuel delivery problem. the injectors are spraying on 12 volts, not sure what the voltage was because we used a test light as a resistor to drop the volts down to 9 or so and they all spray fine and took the DMM and tested them and there all good besides one show's a funky reading and makes the meter bounce around but it still sprays. but when there connected it sprays very little.. if not none.
08-06-2008, 09:46 AM
#12
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the guy said he just paid 200 for the MAF and it looks new but i dont know, how would i go about checking this? and the chts i havent checked. how can i check both of them?
i have a chilton book that my father gave me,
needless to say i will NEVER buy a book from them.
this book doesnt even have a wiring schematic in it.
i have a chilton book that my father gave me,
needless to say i will NEVER buy a book from them.
this book doesnt even have a wiring schematic in it.
08-06-2008, 10:08 AM
#13
Chilton books are only good for the pictures. 
Get a Haynes. Where'd he get the AFM (it's AFM on the 280zx's... MAF is different) ? Is it new or used? The main problems w/ the CHTS (like CW said on the other thread) is the connector will commonly come loose and or corrode.
Check the AFM & CHTS connections.
You can also adjust the AFM spring (there's a sticky thread on doing that). Before adjusting it though, you can pop open the AFM cover & push the door slightly to see if it runs better.
Get a Haynes. Where'd he get the AFM (it's AFM on the 280zx's... MAF is different) ? Is it new or used? The main problems w/ the CHTS (like CW said on the other thread) is the connector will commonly come loose and or corrode. Check the AFM & CHTS connections.
You can also adjust the AFM spring (there's a sticky thread on doing that). Before adjusting it though, you can pop open the AFM cover & push the door slightly to see if it runs better.
08-07-2008, 04:24 PM
#17
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the sensor light on the dash is on for the o2 sensor. it says in the book it comes on after 30,000 miles to replace it. would that make my ECU not give the engine enough fuel? i check all the wiring and everything is clean and connected. the sensor on the head between cyl 5 and 6 was broke which i think was the tempature head sensor. and i JB welded it back together. so idk if that would be the problem or not. could the o2 make the engine do that tho?
08-07-2008, 08:23 PM
#18
Originally Posted by michanic220
the sensor light on the dash is on for the o2 sensor. it says in the book it comes on after 30,000 miles to replace it. would that make my ECU not give the engine enough fuel?
Originally Posted by michanic220
the sensor on the head between cyl 5 and 6 was broke which i think was the tempature head sensor. and i JB welded it back together. so idk if that would be the problem or not.
08-08-2008, 03:10 PM
#19
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why would the degree of the engine matter of how much fuel goes into it?
and that car sat for a year when the guy i bought it from had it. used to run good he said. we had the engine fired up and it was running but not good at all. like it was starving for fuel. i can spray fuel in the intake and it will start, idle perfect and then die from lack of fuel. so thats how i know its not getting enough fuel. + spark, timing and comression is good.
and that car sat for a year when the guy i bought it from had it. used to run good he said. we had the engine fired up and it was running but not good at all. like it was starving for fuel. i can spray fuel in the intake and it will start, idle perfect and then die from lack of fuel. so thats how i know its not getting enough fuel. + spark, timing and comression is good.
08-08-2008, 07:22 PM
#22
Originally Posted by michanic220
why would the degree of the engine matter of how much fuel goes into it?
Originally Posted by michanic220
on the temp head sensor where the sensor mounts into the brass fitting is where it broke off.
08-09-2008, 12:54 AM
#24
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Originally Posted by turboboost
Yes, they fire in a batch.
08-09-2008, 10:36 AM
#25
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They fire less fuel than is needed for one rotation. So you have each runner filling up with 4 spurts of fuel. It is atomized well and floats in the intake running waiting for the valve to open.
It would save a little fuel and be more powerful if each injector fired only when the valve was about to open. That would be sequential firing. Think about how fast the computer would have to work at 6000 rpm to accomplish this. 1975 technology could not do that. The computer was almost the same from 1975-83.
Not until 1987 did the Z get 2 batch firing. (from what I've read)
I think the Z32 might be sequential. 1990+
The 350Z runs carbs. Tripple downdraft Webers!
It would save a little fuel and be more powerful if each injector fired only when the valve was about to open. That would be sequential firing. Think about how fast the computer would have to work at 6000 rpm to accomplish this. 1975 technology could not do that. The computer was almost the same from 1975-83.
Not until 1987 did the Z get 2 batch firing. (from what I've read)
I think the Z32 might be sequential. 1990+
The 350Z runs carbs. Tripple downdraft Webers!
