The 20000 Mile Question
02-26-04, 02:05 PM
#26
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People seems to be having trouble understanding the point I'm trying to get acroos so I'll try and clarify.
IF YOU WANT TO PROVE THE 20K MILES SWITCH RE-ACTIVATES AT 100K, 200K, ETC YOU SHOULD BE PROBING THE DARN SWITCH, NOT SOMETHING ELSE.
phew....
We would be able to settle this whole debate pretty quickly if people would just test the right point instead of testing two steps down the chain. I'm not really rooting for one side or the other, I just want to see an actual answer come out of this.
IF YOU WANT TO PROVE THE 20K MILES SWITCH RE-ACTIVATES AT 100K, 200K, ETC YOU SHOULD BE PROBING THE DARN SWITCH, NOT SOMETHING ELSE.
phew....
We would be able to settle this whole debate pretty quickly if people would just test the right point instead of testing two steps down the chain. I'm not really rooting for one side or the other, I just want to see an actual answer come out of this.
Last edited by theloudroom; 02-26-04 at 02:21 PM.
02-26-04, 05:08 PM
#27
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well just out of curiosity I hooked a digi meter up to pin 1O which is the mileage switch
it showed around 11.83v
my car as 201k miles
where the actual switch is I'm not sure
just was reading the ECU voltage
it showed around 11.83v
my car as 201k miles
where the actual switch is I'm not sure
just was reading the ECU voltage
02-26-04, 08:31 PM
#29
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Wow you guys are still at it--well have at it. Good to hear the discussion and learn a few things. My question was answered, I'm gonna ground the damn wire and then it's done regardless of what the mileage is.
Yea the FSM mentions the port air solenoid, but I wonder what other things it may have left out, like timing and fuel impacts. BTW I mostly trust the FSM but its a trust and confirm affair. [rant]My 84 manual talks about 12B and 13A engines so I know they aren't the best in the world, hell the 88 FSM has these cheapo illustrations and like no real photos--the 84 FSM does[/rant]
I wonder if jinx has any info regarding this switch and how it works inside the ECU.
Scott
Yea the FSM mentions the port air solenoid, but I wonder what other things it may have left out, like timing and fuel impacts. BTW I mostly trust the FSM but its a trust and confirm affair. [rant]My 84 manual talks about 12B and 13A engines so I know they aren't the best in the world, hell the 88 FSM has these cheapo illustrations and like no real photos--the 84 FSM does[/rant]
I wonder if jinx has any info regarding this switch and how it works inside the ECU.
Scott
02-26-04, 08:41 PM
#30
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Originally posted by Rex4Life
Yea the FSM mentions the port air solenoid, but I wonder what other things it may have left out, like timing and fuel impacts.
Yea the FSM mentions the port air solenoid, but I wonder what other things it may have left out, like timing and fuel impacts.
02-26-04, 11:10 PM
#32
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I want 0 volts to simulate above 20,000 miles. Grounding the wire will bring the volts down to 0 (and it must have a pulldown resistor internal to the ECU).
02-27-04, 11:00 AM
#33
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LOUDROOM....You just don't seem to comprehend. Everyone KNOWS the FSM say nothing about the 20,000 mile switch being reactivated when you hit 100,000 miles. THAT is the point and why this is a curiosity.
It DOES happen. I just a few posts ago detailed what my cars are reading. The car with 212,000 miles has no ground being put on the ECU by the milage switch. The other cars do have a ground being put on them by the milage switch.
IF YOU would read the FSM someday, you'd see that the fsm clearly states that when the milage is over 20,000 miles....the Port Air Solenoid is deactivated. The Port Air Solenoid is being used as an example/proof that the milage switch is/is not grounding the pin at the ECU.
It DOES happen. I just a few posts ago detailed what my cars are reading. The car with 212,000 miles has no ground being put on the ECU by the milage switch. The other cars do have a ground being put on them by the milage switch.
IF YOU would read the FSM someday, you'd see that the fsm clearly states that when the milage is over 20,000 miles....the Port Air Solenoid is deactivated. The Port Air Solenoid is being used as an example/proof that the milage switch is/is not grounding the pin at the ECU.
Last edited by HAILERS; 02-27-04 at 11:06 AM.
02-27-04, 11:04 AM
#34
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****well just out of curiosity I hooked a digi meter up to pin 1O which is the mileage switch
it showed around 11.83v
my car as 201k miles
where the actual switch is I'm not sure
just was reading the ECU voltage*******8
Again, RXSPEED87 is one more person who confirms the glitch in the Second Gen ECU/milage switch.
it showed around 11.83v
my car as 201k miles
where the actual switch is I'm not sure
just was reading the ECU voltage*******8
Again, RXSPEED87 is one more person who confirms the glitch in the Second Gen ECU/milage switch.
02-27-04, 11:26 AM
#35
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Originally posted by HAILERS
LOUDROOM....You just don't seem to comprehend.
LOUDROOM....You just don't seem to comprehend.
Originally posted by HAILERS
IF YOU would read the FSM someday, you'd see that the fsm clearly states that when the milage is over 20,000 miles....the Port Air Solenoid is deactivated. The Port Air Solenoid is being used as an example/proof that the milage switch is/is not grounding the pin at the ECU.
IF YOU would read the FSM someday, you'd see that the fsm clearly states that when the milage is over 20,000 miles....the Port Air Solenoid is deactivated. The Port Air Solenoid is being used as an example/proof that the milage switch is/is not grounding the pin at the ECU.
The only way to really know how the ECU controls that solenoid (since you're claiming the FSM is inaccurate) is to disassemble the ECU code. This is why you should probe the switch itself.
02-27-04, 12:10 PM
#36
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NO. I never claimed the FSM is wrong. Quit throwing up strawmen to knock down. Everything I've said indicated the 20,000 mile switch works as advertised by the FSM. Only that it has a quirk. That quirk is that it reactivates when 100,000 miles rolls around. Witness RXSPEED87 above and if you searced you'd find this same 20,000 mile type thread has been posted in the past.
Probe the 20,000 mile switch? I believe it was my fifth post on this thread where I gave out the readings on the ECU pin for a car in the 20,000 mile range and a car out of that range. One is not grounded resulting in 12v, the other is grounded resulting in less than one volt.
The schematic of the combination meter is pretty straight forward. One wire/trace goes to ground, the other goes to pin 1O at the ECU. There's no giant capacitor that gets loaded up over 20,000 miles and suddenly spits out voltage. It's just a switch that puts a ground on pin 1O after 20,000 miles..........and obviously removes that ground when you hit 100,000.1 miles. It's called a glitch. That's the only reason it's of any interest
There is no *probing* to be done. Anymore than I'd *probe* the fifth gear switch which puts a ground on the ECU to trigger a ground on the SplitAir Solenoid.
And to *KNOW* how the ECU controls the Port or Split air solenoids .....is to actually READ the FSM, something you've not done.
Probe the 20,000 mile switch? I believe it was my fifth post on this thread where I gave out the readings on the ECU pin for a car in the 20,000 mile range and a car out of that range. One is not grounded resulting in 12v, the other is grounded resulting in less than one volt.
The schematic of the combination meter is pretty straight forward. One wire/trace goes to ground, the other goes to pin 1O at the ECU. There's no giant capacitor that gets loaded up over 20,000 miles and suddenly spits out voltage. It's just a switch that puts a ground on pin 1O after 20,000 miles..........and obviously removes that ground when you hit 100,000.1 miles. It's called a glitch. That's the only reason it's of any interest
There is no *probing* to be done. Anymore than I'd *probe* the fifth gear switch which puts a ground on the ECU to trigger a ground on the SplitAir Solenoid.
And to *KNOW* how the ECU controls the Port or Split air solenoids .....is to actually READ the FSM, something you've not done.
02-27-04, 01:16 PM
#37
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Originally posted by HAILERS
NO. I never claimed the FSM is wrong.
NO. I never claimed the FSM is wrong.
It's not a "strawman", it's basic reading comprehension. You are claiming the FSM is wrong. It's as simple as that.
Look at page 4A-30 of the 88 FSM.
Originally posted by HAILERS
Two solenoids on the acv. The fwd one is the PortAirSolenoid. The aft one is the SplitAirSolenoid.
There is 12v on the black/white wire all day long as long *** the key is to ON. What triggers the solenoid is the other wire. It puts a ground on the solenoid from the ECU. That will pull the 12v down to waaay low like 1-2volts. So if you back probe the other wire with everything connected up...you should read 12v if the odometer reads over 20,000 miles but about 1-2volts from 0-20,000 miles.
Two solenoids on the acv. The fwd one is the PortAirSolenoid. The aft one is the SplitAirSolenoid.
There is 12v on the black/white wire all day long as long *** the key is to ON. What triggers the solenoid is the other wire. It puts a ground on the solenoid from the ECU. That will pull the 12v down to waaay low like 1-2volts. So if you back probe the other wire with everything connected up...you should read 12v if the odometer reads over 20,000 miles but about 1-2volts from 0-20,000 miles.
"Note: The solenoid valve voltage reading will be a constant below 2.5V (approx.) after the vehicle has accumulated over 20,000 miles."
Originally posted by HAILERS
And to *KNOW* how the ECU controls the Port or Split air solenoids .....is to actually READ the FSM, something you've not done.
And to *KNOW* how the ECU controls the Port or Split air solenoids .....is to actually READ the FSM, something you've not done.
02-27-04, 02:17 PM
#38
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ok the FSM does say over 20k it will shut off
but one wrong part does not negate the whole book
then comes the matter of did they even know it was going to happen
regardless that shouldn't be the point
do you really think you are going to get the matter at hand BICKERING ABOUT A BOOK?
ok if the ECU pin that wer are backprobing is an input to the ECU
then that more or less is probing the switch (if I understand what you guys are talking about)
the switch has an output wire going to the ECU
isn't that the wire we are backprobing guys?
but one wrong part does not negate the whole book
then comes the matter of did they even know it was going to happen
regardless that shouldn't be the point
do you really think you are going to get the matter at hand BICKERING ABOUT A BOOK?
ok if the ECU pin that wer are backprobing is an input to the ECU
then that more or less is probing the switch (if I understand what you guys are talking about)
the switch has an output wire going to the ECU
isn't that the wire we are backprobing guys?
02-27-04, 03:39 PM
#39
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****do you really think you are going to get the matter at hand BICKERING ABOUT A BOOK?***
I'm really not sure what the above means. There's nothing to *get*. It's a simple switch. It puts a ground on a pin on the ECU when twenty grand rolls around. The rest of the time its an open circuit that'll show approx 12v if you probe it with a meter. If you want to see what it effects go to the Relationship Chart in the manual and read the chart (I've posted a jpg of that several times in the past). In my opinion they knew about it when they designed it and didn't give a hoot because the aftereffects are at best not noticeable. You can sit there watching a afr meter (wideband) and make and break that ground and it does nadda for the afr or timing.....at idle.
I'm really not sure what the above means. There's nothing to *get*. It's a simple switch. It puts a ground on a pin on the ECU when twenty grand rolls around. The rest of the time its an open circuit that'll show approx 12v if you probe it with a meter. If you want to see what it effects go to the Relationship Chart in the manual and read the chart (I've posted a jpg of that several times in the past). In my opinion they knew about it when they designed it and didn't give a hoot because the aftereffects are at best not noticeable. You can sit there watching a afr meter (wideband) and make and break that ground and it does nadda for the afr or timing.....at idle.
02-27-04, 03:49 PM
#40
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Originally posted by HAILERS
In my opinion they knew about it when they designed it and didn't give a hoot because the aftereffects are at best not noticeable. You can sit there watching a afr meter (wideband) and make and break that ground and it does nadda for the afr or timing.....at idle.
In my opinion they knew about it when they designed it and didn't give a hoot because the aftereffects are at best not noticeable. You can sit there watching a afr meter (wideband) and make and break that ground and it does nadda for the afr or timing.....at idle.
It may only check that signal every time you start the car, not continuously, while you're driving.
03-29-04, 09:44 PM
#41
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Sorry to bump this but...
It kinda was interesting to me.
The guy who has the RTek 7 on www.pocketlogger.com has disassembled the code on the ECU...
I was hoping maybe he could stop by and see what's up....
-Jon
I wish I knew his S/N though... I'll search in a bit.
It kinda was interesting to me.
The guy who has the RTek 7 on www.pocketlogger.com has disassembled the code on the ECU...
I was hoping maybe he could stop by and see what's up....
-Jon
I wish I knew his S/N though... I'll search in a bit.
03-30-04, 12:16 AM
#42
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Originally posted by theloudroom
It may only check that signal every time you start the car, not continuously, while you're driving.
It may only check that signal every time you start the car, not continuously, while you're driving.
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