Good morning,

A hose got cut on our 2000 Blazer 4x4 that was coming from the secondary air injection pump, per a 40 years in the business certified mechanic. Just what does this injection pump do?

It needs to be replaced and there are a number of them listed on the web such as Amazon. Once I get one, where does it go? I can't seem to find a terminal end point.

Also, does this need any sort of a filter at its endpoint from the pump?

Any suggestions would be helpful as it is now jacked up in the garage waiting for me to fix it.

Thanks in advance for your help.

 

This is a vane pump that injects fresh air into the exhaust stream during engine warm up to lower emissions on a cold engine. If you are older like me, It is also sometimes called a smog pump. There may also be other components like a check valve or solenoid. I don't know about an air filter. I do not know the particulars of location and removal on your vehicle. If nobody chimes in with repair info you might consider a Mitchel1 DIY or Alldata subscription for your vehicle. One year is on the order of $25.


George

 

This might help you

https://www.justanswer.com/gm/32bqc-...mc-sonoma.html


George

 

This video is for the 4 cylinder S10 but the previous link I posted suggests that the pump set up is the same for your truck. This is my favorite repair guy on the internet BTW:



George

 

Make sure the check valves mounted in the exhaust manifolds are working. It is fairly common for these to malfunction, then hot exhaust blows back into the AIR pump system and ruins/melts it. Also there was a problem on these Blazers with moisture running down the inlet into the pump and corroding it. The cure is the relocation kit supplied with the AC Delco pumps that puts the inlet along side the top of the radiator. Not the easiest thing to install, but few things are easy in a Blazer. I had to put one of these on mine, along with new check valves in the exhaust manifolds and the rubber hoses connecting them to the pipes.

If you hear exhaust noises, then the check valves are definitely bad. Those are quite difficult to replace IMHO (at least without heating with a torch). Careful with these - the curly-Q tubes are over $100 each if you can find them. I was able to unbolt the check valve assemblies from the manifolds and then split the nut where they screwed onto the tube with a Dremel cutting wheel. I was able to find the correct gaskets for the check valve assembly tube mounting and the correct rubber hoses when going back together with the check valves on ebay - it has been a while, though.

https://www.rockauto.com/en/parts/gm...smog+pump,4920

https://www.carid.com/acdelco/gm-ori...7&url=10908085