Idle adjustments
05-15-2010, 05:22 PM
#51
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Car: 89 FORMULA FIREBIRD, 86 CHEVY CAMARO
Engine: L98, LB9 RESPECTIVLY
Transmission: 700 R4 (BOTH)
Re: Idle adjustments
The ecm has a common ground that fires all 8 injectors at the same time on the negative side, the 12v pos however is 2 seperate circuits with 2 seperate fuses marked inj1 and inj2 if one of those fuses is blown that bank wont fire.
Happened in my 89 one night going home from work, had to drive home on 4 cylinders.
Happened in my 89 one night going home from work, had to drive home on 4 cylinders.
05-15-2010, 09:28 PM
#52
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Car: 1987 IROC-Z
Engine: 305 TPI
Transmission: 700r4
Re: Idle adjustments
How did you miss that; should have sounded like sh**
Two seperate injector circuits ; one for each bank.
12V to injector , injectors controlled by going to ground at the ECM
Have you checked the injector fuses?
Do you have 12V on one side of the injector plugs ( pink / blk wire ? ) in the bad bank?
Is the other terminal of injector plug open circuit ; as in not to ground ?
Two seperate injector circuits ; one for each bank.
12V to injector , injectors controlled by going to ground at the ECM
Have you checked the injector fuses?
Do you have 12V on one side of the injector plugs ( pink / blk wire ? ) in the bad bank?
Is the other terminal of injector plug open circuit ; as in not to ground ?
But i havent checked my injector fuses, but as i was reading my chiltons it said that to do a valve adjustment that i must put the no. 1 cylinder on TDC and then adjust intake valves on cylinders 1,2,5,7. and exhaust valves on 1.3.4.8 and then put the no.6 cylinder on TDC and adjust the intake valves on cylinders 3,4,6,8 and then the exhaust valves on cylinders 2,5,6,7. But when i did the valves the first time once i put the heads back on i did each cylinder individually, so i det the no.1 cyl. on TDC and adjusted both the intake and exhaust valves on the no 1 cylinder, then proceeded to do each cylinder like that, so now what im thinking is that the entire passengers side is 180 degress off.... is that a possibility? But im going to check the ground and the fuses to my fuel rails late tonight.
05-15-2010, 09:36 PM
#53
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Car: 1987 IROC-Z
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Re: Idle adjustments
So i just quickly looked at my fuse box and it seems that Im missing a 10amp fuse that goes into the slot thats labels FP/Inj2..... thats def the problem isnt it??
05-15-2010, 10:29 PM
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05-15-2010, 11:34 PM
#56
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Car: 88' IROCZ
Engine: 388 TPI Motown 350 Race block
Transmission: 700R4
Axle/Gears: 2.77
Re: Idle adjustments
The ecm has a common ground that fires all 8 injectors at the same time on the negative side, the 12v pos however is 2 seperate circuits with 2 seperate fuses marked inj1 and inj2 if one of those fuses is blown that bank wont fire.
Happened in my 89 one night going home from work, had to drive home on 4 cylinders.
Happened in my 89 one night going home from work, had to drive home on 4 cylinders.
05-23-2011, 02:28 AM
#57
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Car: 1987 z28
Engine: 350 corvette
Re: Idle adjustments
mechanic1992, sorry for asking this, but you did put the flat tappet lifters on a flat tappet cam, right?
check the air boot between the mass air flow sensor and throttle body. one way to do it is with the motor running at idle in park, lightly pull the boot away from the throttle body. next lightly pull the MAF sensor away from the air boot. there shouldn't be any noticeable change in the idle.
if there is, closely check the boot for any cracks or other damage.
if there wasn't any change, lightly wiggle the MAF sensor connector.
next do a tap test on the MAF sensor.
with a small wrench or screw driver, lightly tap on the MAF. you don't need to smack the sensor, just tap it about as hard as if you dropped a 1/2 wrench 3~4 inches.
if any of those results in a noticeable change in the idle, something isn't right and needs to be repaired.
Chevy86, before you can reprogram a chip, you must first erase it.
for this reason a PROM isn't re-programmable.
EPROMs with a window can usually be reprogramed, but exposing them to UV
light to erase them takes a toll on them as does the programing itself and they can fail at any time.
EEPROMs can normally be erased and programed many times before they fail.
telling someone they have been "had" by another member isn't a good thing.
its a form of trolling, which isn't allowed on this site.
besides, its just bad form.
IIRC, were you not recently on probation for something similar?
check the air boot between the mass air flow sensor and throttle body. one way to do it is with the motor running at idle in park, lightly pull the boot away from the throttle body. next lightly pull the MAF sensor away from the air boot. there shouldn't be any noticeable change in the idle.
if there is, closely check the boot for any cracks or other damage.
if there wasn't any change, lightly wiggle the MAF sensor connector.
next do a tap test on the MAF sensor.
with a small wrench or screw driver, lightly tap on the MAF. you don't need to smack the sensor, just tap it about as hard as if you dropped a 1/2 wrench 3~4 inches.
if any of those results in a noticeable change in the idle, something isn't right and needs to be repaired.
Chevy86, before you can reprogram a chip, you must first erase it.
for this reason a PROM isn't re-programmable.
EPROMs with a window can usually be reprogramed, but exposing them to UV
light to erase them takes a toll on them as does the programing itself and they can fail at any time.
EEPROMs can normally be erased and programed many times before they fail.
telling someone they have been "had" by another member isn't a good thing.
its a form of trolling, which isn't allowed on this site.
besides, its just bad form.
IIRC, were you not recently on probation for something similar?
like what?
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