air pump
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Originally Posted by Kirpich,Nov 30 2008, 10:18 PM
There is a box behind driver side fender, called Air Pump Current Sensor, it actually measures that the Airpump relay is pulling so many amps whenever the pump is supposed to be pumping. Well, if electric current is correct, the Current Sensor sends a 2.5V signal to the ecu, I measured. So I'm gonna go to RadioShack, buy an adjusable voltage regulator, set it to 2.5V, and hook it up like so:
pump relay 12V out to the voltage regulator in, voltage regulator out (2.5V) to current sensing signal wire out, and the ecu will think the pump is pumping.
pump relay 12V out to the voltage regulator in, voltage regulator out (2.5V) to current sensing signal wire out, and the ecu will think the pump is pumping.
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From: las vegas
Originally Posted by Kirpich,Nov 30 2008, 11:18 PM
There is a box behind driver side fender, called Air Pump Current Sensor, it actually measures that the Airpump relay is pulling so many amps whenever the pump is supposed to be pumping. Well, if electric current is correct, the Current Sensor sends a 2.5V signal to the ecu, I measured. So I'm gonna go to RadioShack, buy an adjusable voltage regulator, set it to 2.5V, and hook it up like so:
pump relay 12V out to the voltage regulator in, voltage regulator out (2.5V) to current sensing signal wire out, and the ecu will think the pump is pumping.
pump relay 12V out to the voltage regulator in, voltage regulator out (2.5V) to current sensing signal wire out, and the ecu will think the pump is pumping.
that doesnt mean anything, the 02's will still be looking for the flow of air. The car will be watching the IAC valve adjusting it accordingly for the extra amp load on the alternator, the rear 02 will then look for the cat to light off.
What your doing is cool, but it isnt going to save you from MIL. Like i said, we need to find a way to remove this from the ecu, but i dont think any normal person has that info, someone who builds ecu's maybe, most of us, doubt it.
Joined: Aug 2006
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From: Huntsville, AL
Originally Posted by Kirpich,Dec 1 2008, 01:18 AM
There is a box behind driver side fender, called Air Pump Current Sensor, it actually measures that the Airpump relay is pulling so many amps whenever the pump is supposed to be pumping. Well, if electric current is correct, the Current Sensor sends a 2.5V signal to the ecu, I measured. So I'm gonna go to RadioShack, buy an adjusable voltage regulator, set it to 2.5V, and hook it up like so:
pump relay 12V out to the voltage regulator in, voltage regulator out (2.5V) to current sensing signal wire out, and the ecu will think the pump is pumping.
pump relay 12V out to the voltage regulator in, voltage regulator out (2.5V) to current sensing signal wire out, and the ecu will think the pump is pumping.
It turns on the pump briefly and looks at the O2 Sensor voltage to see if it reads lean.
So you will also need to wire up another voltage regulator to a relay that sends the stock ECU a Lean voltage during the secondary check.
Sounds like you know your way around electronics but just in case use a 5 pin relay which when not energized the O2 voltage is normal and when energized the voltage is clamped lean but the voltage clamp is not back feed into the sensor; which could possibly fry the sensor.
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^Yeah, the green tree-huggin' hippies are all over car design and engineering, aren't they? Poor California automobile enthusiasts suffer the most.
As for the secondary check after the engine is warmed up, here's what I'm seeing:
I installed the turbo, and was doing the Emanage tuning for driveability to the tuner. The airpump hose vacuum-activated valve on the manifold is removed and capped off, so the airpump is just spinning without actually getting any air into the system. I only have an occasional "secondary air injection system" CEL that has something to do with hose routing, so it is doing something what ya'll describe, but only 1 out of 3 or 4 completely cold starts. So the system is like almost not seeing it, just barely. I'm still looking into it, though.
As for the secondary check after the engine is warmed up, here's what I'm seeing:
I installed the turbo, and was doing the Emanage tuning for driveability to the tuner. The airpump hose vacuum-activated valve on the manifold is removed and capped off, so the airpump is just spinning without actually getting any air into the system. I only have an occasional "secondary air injection system" CEL that has something to do with hose routing, so it is doing something what ya'll describe, but only 1 out of 3 or 4 completely cold starts. So the system is like almost not seeing it, just barely. I'm still looking into it, though.
Joined: Aug 2006
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From: Huntsville, AL
Your CEL most likely is air flow is not correct.
Since it is not seeing lean on the 02 sensor during the secondary check.
and it takes 3 to 4 reoccurrences of this to set the CEL.
So you will not see it every time.
Since it is not seeing lean on the 02 sensor during the secondary check.
and it takes 3 to 4 reoccurrences of this to set the CEL.
So you will not see it every time.
