Secondary Air Injection
Instructor
Joined: Nov 2004
Posts: 113
Likes: 2
1. Secondary air injection injects air into the exhaust manifold to oxidise the carbon monoxide (CO) to carbon dioxide (CO2). Consequently it has nothing to do with AFR.
2. Your engine could be running lean at WOT for many reasons:
- too much air (leaking intake manifold seals, etc.)
- not enough fuel due to either mechanical problems (plugged injectors, etc) or electrical problems (for example TPS sensor malfunctions, so the ECU never gets to know that engine is running WOT and does not enrich the mixture appropriately).
What codes is the ECU throwing? Any mods?
2. Your engine could be running lean at WOT for many reasons:
- too much air (leaking intake manifold seals, etc.)
- not enough fuel due to either mechanical problems (plugged injectors, etc) or electrical problems (for example TPS sensor malfunctions, so the ECU never gets to know that engine is running WOT and does not enrich the mixture appropriately).
What codes is the ECU throwing? Any mods?
Thread Starter
Burning Brakes
Joined: May 2003
Posts: 990
Likes: 0
From: Germantown TN
1. Secondary air injection injects air into the exhaust manifold to oxidise the carbon monoxide (CO) to carbon dioxide (CO2). Consequently it has nothing to do with AFR.
2. Your engine could be running lean at WOT for many reasons:
- too much air (leaking intake manifold seals, etc.)
- not enough fuel due to either mechanical problems (plugged injectors, etc) or electrical problems (for example TPS sensor malfunctions, so the ECU never gets to know that engine is running WOT and does not enrich the mixture appropriately).
What codes is the ECU throwing? Any mods?
2. Your engine could be running lean at WOT for many reasons:
- too much air (leaking intake manifold seals, etc.)
- not enough fuel due to either mechanical problems (plugged injectors, etc) or electrical problems (for example TPS sensor malfunctions, so the ECU never gets to know that engine is running WOT and does not enrich the mixture appropriately).
What codes is the ECU throwing? Any mods?
The car is not running lean. It is running pig rich. AFR of 10.5 at WOT. The only code it has is the Secondary Air Injection malfunction code.
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Verdad Gallardo
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
You're probaby seeing the normal "pig rich" AFR that these cars typically have from the factory.
How was the AFR measured (accurately) ? Wide band O2 sensor used by a shop that knows what they're doing?
How was the AFR measured (accurately) ? Wide band O2 sensor used by a shop that knows what they're doing?
Thread Starter
Burning Brakes
Joined: May 2003
Posts: 990
Likes: 0
From: Germantown TN
. I wish I could post my dyno sheet but I don't have a scanner.
