TPS/IDLE Adjustment Issue
06-05-11, 12:28 AM
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TPS/IDLE Adjustment Issue
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ok so heres the deal, i checked tps over and over i can set it closed at 1k ohms and wide open at 5k ohms. it still has a studder usually lower rpms or 1.5k rpm but i also have ben trying to find this bAC idle adjustment screw, and can not find one that looks like every picture that i have came across. i see the BAC solenoid but it does not have a adjustment piece. its just there and plugs into harness. am i missing something here???
the red was the idle adjustment that i messed with, the green was the tps and adjustment screw
this what i thought was the BAC in the back of the IM, as your link and other link showed me this should have a adjustment screw which i did not find anywhere behind the IM.
this was the solenoid i saw on the FSM but it did not say any way to adjust it just to ohm out the resistance and if need to replace.
Now my car worked perfect before and did not have a studder anywhere in the power band, but ever since ive messed with the top two adjustments its been a b*tch to get back to normal. if anyone can figure out this mystery that be great !!!!
ok so heres the deal, i checked tps over and over i can set it closed at 1k ohms and wide open at 5k ohms. it still has a studder usually lower rpms or 1.5k rpm but i also have ben trying to find this bAC idle adjustment screw, and can not find one that looks like every picture that i have came across. i see the BAC solenoid but it does not have a adjustment piece. its just there and plugs into harness. am i missing something here???
the red was the idle adjustment that i messed with, the green was the tps and adjustment screw
this what i thought was the BAC in the back of the IM, as your link and other link showed me this should have a adjustment screw which i did not find anywhere behind the IM.
this was the solenoid i saw on the FSM but it did not say any way to adjust it just to ohm out the resistance and if need to replace.
Now my car worked perfect before and did not have a studder anywhere in the power band, but ever since ive messed with the top two adjustments its been a b*tch to get back to normal. if anyone can figure out this mystery that be great !!!!
06-05-11, 12:43 AM
#2
Look at the fuel and emissions control section for a non turbo engine. It explains everything. You must jumper the initial set connector to adjust the idle speed. That cancels out the idle feedback system so the ECU doesn't try to "out learn" your idle adjustments. This isn't some Rx-7 thing. It's a typical way of adjusting the idle on many 80s or 90s cars. Either you put it into a diagnostic mode or you unplug the idle air control valve.
On the non turbo engines, the air bypass screw is circled in red on your first pic. On the USDM turbo engines, it is on the BAC valve itself. USDM Non turbo engines have blank casting on the BAC valve for the adjuster screw; it's simply not there. A turbo throttlebody is basically an upside down N/A throttlebody; it has blank casting for the air bypass screw. On the FD throttlebody/UIM, the air bypass screw is between the bottom two studs. Instead of having a dedicated hose, the BAC/ISC valve bolts to the intake manifold which is a common design.
On the non turbo engines, the air bypass screw is circled in red on your first pic. On the USDM turbo engines, it is on the BAC valve itself. USDM Non turbo engines have blank casting on the BAC valve for the adjuster screw; it's simply not there. A turbo throttlebody is basically an upside down N/A throttlebody; it has blank casting for the air bypass screw. On the FD throttlebody/UIM, the air bypass screw is between the bottom two studs. Instead of having a dedicated hose, the BAC/ISC valve bolts to the intake manifold which is a common design.
06-05-11, 12:53 AM
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Look at the fuel and emissions control section for a non turbo engine. It explains everything. You must jumper the initial set connector to adjust the idle speed. That cancels out the idle feedback system so the ECU doesn't try to "out learn" your idle adjustments. This isn't some Rx-7 thing. It's a typical way of adjusting the idle on many 80s or 90s cars. Either you put it into a diagnostic mode or you unplug the idle air control valve.
On the non turbo engines, the air bypass screw is circled in red on your first pic. On the USDM turbo engines, it is on the BAC valve itself. USDM Non turbo engines have blank casting on the BAC valve for the adjuster screw; it's simply not there. A turbo throttlebody is basically an upside down N/A throttlebody; it has blank casting for the air bypass screw. On the FD throttlebody/UIM, the air bypass screw is between the bottom two studs. Instead of having a dedicated hose, the BAC/ISC valve bolts to the intake manifold which is a common design.
On the non turbo engines, the air bypass screw is circled in red on your first pic. On the USDM turbo engines, it is on the BAC valve itself. USDM Non turbo engines have blank casting on the BAC valve for the adjuster screw; it's simply not there. A turbo throttlebody is basically an upside down N/A throttlebody; it has blank casting for the air bypass screw. On the FD throttlebody/UIM, the air bypass screw is between the bottom two studs. Instead of having a dedicated hose, the BAC/ISC valve bolts to the intake manifold which is a common design.
the picture i have of the connector is a little blurry do you or anyone have a better picture or description of it?
06-05-11, 08:38 AM
#5
Rotary Freak
The variable resistor is near the pressure/boost sensor. Somewhat oval in shape. Has a pillar in the middle of it and down in the pillar is a screw. The screw only turns about three quarters turn each way. Left for learner and right for richer.
The screw on the top of the dynamic chamber is an air bypass screw. All the way in cuts down on air and outwards lets more air bypass the throttle plates.
The engine water MUST BE FULLY HOT when you adjust the TPS.
What's the engine idle at now? Fully hot and at idle?
No idle scew on the BAC as mentioned above........on 86 non turbo cars.
In your last picture..........under the alternator I see a elect connector not connected to anyting. IS this the two wire plug for your alternator??? IF so connect it to the alternator.
Your second to the last picture is the damper for the throttle. Called a DASHPOT and has honorable mention in the Fuel and Emissions Section of the FSM. Leave it alone. In your case if you've adjsuted it and your idle is high, try backing it off to lower the idle. IF the idle does not change then put it back exactly where it was prior to adjusting it and or follow the FSM on how to adjust it.
Did I mention the engine water must be fully hot while adjusting the TPS?
Personally I don't use the ohm method of adjusting thae TPS. I fully warm the engine up and with ALL electrical plugs connected on every damn thing on the car............backprobe the green/red wire on the TPS connector (on the harness side of the connector NOT the TPS pigtail side). IF it does not read one volt dc then turn the TPS screw til it does. Done and finished IF the engine was fully HOT. No need to jumper squat doing this. No LED lights needed. No factory adjustment tool etc.
That's a decent looking engine. Nothing has been cut up or thrown away. Nothing looks scewball aftermarket hackup.
The screw on the top of the dynamic chamber is an air bypass screw. All the way in cuts down on air and outwards lets more air bypass the throttle plates.
The engine water MUST BE FULLY HOT when you adjust the TPS.
What's the engine idle at now? Fully hot and at idle?
No idle scew on the BAC as mentioned above........on 86 non turbo cars.
In your last picture..........under the alternator I see a elect connector not connected to anyting. IS this the two wire plug for your alternator??? IF so connect it to the alternator.
Your second to the last picture is the damper for the throttle. Called a DASHPOT and has honorable mention in the Fuel and Emissions Section of the FSM. Leave it alone. In your case if you've adjsuted it and your idle is high, try backing it off to lower the idle. IF the idle does not change then put it back exactly where it was prior to adjusting it and or follow the FSM on how to adjust it.
Did I mention the engine water must be fully hot while adjusting the TPS?
Personally I don't use the ohm method of adjusting thae TPS. I fully warm the engine up and with ALL electrical plugs connected on every damn thing on the car............backprobe the green/red wire on the TPS connector (on the harness side of the connector NOT the TPS pigtail side). IF it does not read one volt dc then turn the TPS screw til it does. Done and finished IF the engine was fully HOT. No need to jumper squat doing this. No LED lights needed. No factory adjustment tool etc.
That's a decent looking engine. Nothing has been cut up or thrown away. Nothing looks scewball aftermarket hackup.
06-05-11, 07:47 PM
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The variable resistor is near the pressure/boost sensor. Somewhat oval in shape. Has a pillar in the middle of it and down in the pillar is a screw. The screw only turns about three quarters turn each way. Left for learner and right for richer.
The screw on the top of the dynamic chamber is an air bypass screw. All the way in cuts down on air and outwards lets more air bypass the throttle plates.
The engine water MUST BE FULLY HOT when you adjust the TPS.
What's the engine idle at now? Fully hot and at idle?
No idle scew on the BAC as mentioned above........on 86 non turbo cars.
In your last picture..........under the alternator I see a elect connector not connected to anyting. IS this the two wire plug for your alternator??? IF so connect it to the alternator.
Your second to the last picture is the damper for the throttle. Called a DASHPOT and has honorable mention in the Fuel and Emissions Section of the FSM. Leave it alone. In your case if you've adjsuted it and your idle is high, try backing it off to lower the idle. IF the idle does not change then put it back exactly where it was prior to adjusting it and or follow the FSM on how to adjust it.
Did I mention the engine water must be fully hot while adjusting the TPS?
Personally I don't use the ohm method of adjusting thae TPS. I fully warm the engine up and with ALL electrical plugs connected on every damn thing on the car............backprobe the green/red wire on the TPS connector (on the harness side of the connector NOT the TPS pigtail side). IF it does not read one volt dc then turn the TPS screw til it does. Done and finished IF the engine was fully HOT. No need to jumper squat doing this. No LED lights needed. No factory adjustment tool etc.
That's a decent looking engine. Nothing has been cut up or thrown away. Nothing looks scewball aftermarket hackup.
The screw on the top of the dynamic chamber is an air bypass screw. All the way in cuts down on air and outwards lets more air bypass the throttle plates.
The engine water MUST BE FULLY HOT when you adjust the TPS.
What's the engine idle at now? Fully hot and at idle?
No idle scew on the BAC as mentioned above........on 86 non turbo cars.
In your last picture..........under the alternator I see a elect connector not connected to anyting. IS this the two wire plug for your alternator??? IF so connect it to the alternator.
Your second to the last picture is the damper for the throttle. Called a DASHPOT and has honorable mention in the Fuel and Emissions Section of the FSM. Leave it alone. In your case if you've adjsuted it and your idle is high, try backing it off to lower the idle. IF the idle does not change then put it back exactly where it was prior to adjusting it and or follow the FSM on how to adjust it.
Did I mention the engine water must be fully hot while adjusting the TPS?
Personally I don't use the ohm method of adjusting thae TPS. I fully warm the engine up and with ALL electrical plugs connected on every damn thing on the car............backprobe the green/red wire on the TPS connector (on the harness side of the connector NOT the TPS pigtail side). IF it does not read one volt dc then turn the TPS screw til it does. Done and finished IF the engine was fully HOT. No need to jumper squat doing this. No LED lights needed. No factory adjustment tool etc.
That's a decent looking engine. Nothing has been cut up or thrown away. Nothing looks scewball aftermarket hackup.
jumper connection correct me if i am wrong.
<a href="http://s1136.photobucket.com/albums/n485/RickysFC/?action=view&current=fffff.jpg" target="_blank"><img src="http://i1136.photobucket.com/albums/n485/RickysFC/fffff.jpg" border="0" alt="Photobucket"></a>
missing variable resistor???? as the fsm says it should of been right here, ive checked up and down the harness and cant find it.
<a href="http://s1136.photobucket.com/albums/n485/RickysFC/?action=view&current=sdfs.jpg" target="_blank"><img src="http://i1136.photobucket.com/albums/n485/RickysFC/sdfs.jpg" border="0" alt="Photobucket"></a>
i had warmed up car and also had the jumper wire connected and adjusted the to air valve on IM, got it to 750-800rpm but the air valve was almost pretty much closed (twisted all to the right).
when you meant by checking the tps should the car be on and running or just key turned to ignition.
06-05-11, 07:56 PM
#7
Rotary Freak
The varible resistor is on the right side of the engine bay near the area of the boost/pressure sensor/afm filter area. Take a picture of that area. You took a picture of the left side of the engine bay for some reason or other.
Yes, green check connector that gets jumpered with a piece of bare wire or paper clip or ???
The screw on top of the Dynamic chamber ..........turned clockwise lessens the air bypassed and turning it anti clockwise bypasses more air.
750-800 is a normal idle speed. IF the idle is a bit irregular..........adding more IDLE fuel using the variable resistor will help make it less irregular. The variable resistor has a L and a R letter on it near its pedestal. R stands for ............. and L stands for .............. The screw has STOPS. Do not try to go past the STOPS. The full turn of the screw is approx 3/4 of a full turn the last time I looked.
Checking the TPS question................the engine NEEDS to be fully warmed up. Like 180*F. The car can be idling or you can turn it off then put the key to ON, but if you do that you need to check the voltage output of the TPS green/red wire in say..............the next fifteen minutes in the summer time so the water thermowax does not start retreating ........I mean its piston will retreat.
Take a picture of the TPS elect plug for ref.
Ummmm, yummy. Plastic tie wraps routing electrical wiring. Love it. I know better but do it myself. I know right from wrong but that doesn't mean I'll always do right.
Yes, green check connector that gets jumpered with a piece of bare wire or paper clip or ???
The screw on top of the Dynamic chamber ..........turned clockwise lessens the air bypassed and turning it anti clockwise bypasses more air.
750-800 is a normal idle speed. IF the idle is a bit irregular..........adding more IDLE fuel using the variable resistor will help make it less irregular. The variable resistor has a L and a R letter on it near its pedestal. R stands for ............. and L stands for .............. The screw has STOPS. Do not try to go past the STOPS. The full turn of the screw is approx 3/4 of a full turn the last time I looked.
Checking the TPS question................the engine NEEDS to be fully warmed up. Like 180*F. The car can be idling or you can turn it off then put the key to ON, but if you do that you need to check the voltage output of the TPS green/red wire in say..............the next fifteen minutes in the summer time so the water thermowax does not start retreating ........I mean its piston will retreat.
Take a picture of the TPS elect plug for ref.
Ummmm, yummy. Plastic tie wraps routing electrical wiring. Love it. I know better but do it myself. I know right from wrong but that doesn't mean I'll always do right.
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06-05-11, 11:10 PM
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The varible resistor is on the right side of the engine bay near the area of the boost/pressure sensor/afm filter area. Take a picture of that area. You took a picture of the left side of the engine bay for some reason or other.
Yes, green check connector that gets jumpered with a piece of bare wire or paper clip or ???
The screw on top of the Dynamic chamber ..........turned clockwise lessens the air bypassed and turning it anti clockwise bypasses more air.
750-800 is a normal idle speed. IF the idle is a bit irregular..........adding more IDLE fuel using the variable resistor will help make it less irregular. The variable resistor has a L and a R letter on it near its pedestal. R stands for ............. and L stands for .............. The screw has STOPS. Do not try to go past the STOPS. The full turn of the screw is approx 3/4 of a full turn the last time I looked.
Checking the TPS question................the engine NEEDS to be fully warmed up. Like 180*F. The car can be idling or you can turn it off then put the key to ON, but if you do that you need to check the voltage output of the TPS green/red wire in say..............the next fifteen minutes in the summer time so the water thermowax does not start retreating ........I mean its piston will retreat.
Take a picture of the TPS elect plug for ref.
Ummmm, yummy. Plastic tie wraps routing electrical wiring. Love it. I know better but do it myself. I know right from wrong but that doesn't mean I'll always do right.
Yes, green check connector that gets jumpered with a piece of bare wire or paper clip or ???
The screw on top of the Dynamic chamber ..........turned clockwise lessens the air bypassed and turning it anti clockwise bypasses more air.
750-800 is a normal idle speed. IF the idle is a bit irregular..........adding more IDLE fuel using the variable resistor will help make it less irregular. The variable resistor has a L and a R letter on it near its pedestal. R stands for ............. and L stands for .............. The screw has STOPS. Do not try to go past the STOPS. The full turn of the screw is approx 3/4 of a full turn the last time I looked.
Checking the TPS question................the engine NEEDS to be fully warmed up. Like 180*F. The car can be idling or you can turn it off then put the key to ON, but if you do that you need to check the voltage output of the TPS green/red wire in say..............the next fifteen minutes in the summer time so the water thermowax does not start retreating ........I mean its piston will retreat.
Take a picture of the TPS elect plug for ref.
Ummmm, yummy. Plastic tie wraps routing electrical wiring. Love it. I know better but do it myself. I know right from wrong but that doesn't mean I'll always do right.
assuming this connector is what should have been the variable resistor i am SOL arent I?
will get pics tomorow of other side of engine bay
06-05-11, 11:35 PM
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i came to conclusion that i am missing my variable resistor. i cant find it at al and i am assuming that this random connctor near the pressure sensor is the conncetor for it. so i went ahead and bought a used one. so ill re do everything this coming up weekend if i get it in time. and go from there. thanks for everyones help. wish me luck. 
06-06-11, 03:59 PM
#10
Rotary Freak
The variable resistors has a round elect plug with three wires in it. I'll take a picture later in the day/week.
If removed from the car, the ECU defaults to a given value............maybe half of its potential output I THINK.
If removed from the car, the ECU defaults to a given value............maybe half of its potential output I THINK.
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