Emission Problems

chevrolet
s-10

#1

I have a 2002 S10 pickup with 4 cylinder engine. There have been four failures of the pump (blower)that provides air to the Catalytic converter. Fortunately they have been covered by warrantee. Each time water has been the culprit. The garage has moved the intake hose away from the AC compressor thinking it was picking up moisture. The check engine light has come on again. Has anyone had this problem and what corrected it other than moving to a desert. Unhappy Mainer


#2

Are you speaking of a secondary air injection pump? I would not say this provided air to the catalytic converter. If I am speaking of the wrong part,correct me.

What has been the failure(s) the pumps have shown? Locking up? perhaps your pump is not at fault and some other part of the system is at fault.

Let us know the codes.


#3

When the engine is warming up the secondary air pump is sending air to the exhaust manifolds through a one way check valve. When the engine is warmed up the air pump is either switched off or the air flow is switched to the post NOX part of the catalytic converter. If the check valve is leaking exhaust gases back into the air pump, the water in the exhaust will condense and deposit that in the air pump. One check is to disconnect the secondary air pipe upstream of the check valve and see if there are exhaust pulses coming back.

Hope that is what it is.


#4

You should always get the code anytime the light comes on. It should be in the formation [P1234} That would help a lot.


#5

I think I need to explain in a little more detail if that is possible for someone who does not know what he is talking about. The service manager did call it a pump. His explanation was that if the O2 sensor senses low oxygen it signals the control module which in turn starts the pump. He did not give me the code but said that every time this happens the control module indicates it is the pump. The idiot light comes on after I have driven a few miles. I should add that we have had record precipitation this spring and summer with lower than normal temperatures for Maine. It hasn’t been too bad except for the moss growing on my house roof and between my toes.


#6

Yes I do see the reason why you were told the pump supplies air to the cat,just not up on my diverter valve outputs.

That being said there certainly is more to the system than the pump. The problem I can see with the pump is locking up due to moisture,are the pumps locking up? If not there certainly are more potential points for a failure in this system and after 4 pumps its time to take a look at some of the other components.