e320 / Code 4 / So what now?

[mcvespa]

Hi everyone,

My check engine light came on once again. With the key in the on position (car off) I held down the button under the hood for 3-4 seconds. The light then flashed 4 times. I did it again to see if there were any other codes and it flashed 4 times once again. I then cleared the codes by holding the button down for more than 6 seconds.

Code 4 states: Air injection inoperative. So what now? What are the components that may be at fault here?

I should point out that the car runs fine and I recently replaced the air filter.

Thanks,
Michael
95 e320 Wagon / 100K

[Arthur Dalton]

It's that Bean Town air screwin' up your injection..

First check is to see if the Air Pump runs when you first start a Cold car..

Does it??

[mcvespa]

Could be the Bean Town air for sure! LOL

How do I know if the air pump is running?

Thanks Arthur!

[Arthur Dalton]

You have to start the car with the hood open..it is the belt driven pump over by the air-filter ... you can hear it run.. It only runs when the engine is cold at start-up and it only run for a min or so.
It is emmissions device that pumps air into the exhaust just til the cat heats up. Usually when that code comes up, my firsts check [ after I know it is actually coming ON ] is to pull that plastic cover in front of the engine..you will then see a white plastic vac line crossing over to a couple of valves ..that line always cracks and breaks and when it does , the Air Pump valve does not work so that code comes up as #4
I would also look at all those lines in that area seeing thatyou just worked in that space. May just have a vac line off.

Check those out and see if you find anything..

[mcvespa]

Thanks Arthur! I'll check it out tomorrow and will post back to let everyone know my findings.

Michael

[esanding]

Originally Posted by mcvespa

Hi everyone,

My check engine light came on once again. With the key in the on position (car off) I held down the button under the hood for 3-4 seconds. The light then flashed 4 times. I did it again to see if there were any other codes and it flashed 4 times once again. I then cleared the codes by holding the button down for more than 6 seconds.

Code 4 states: Air injection inoperative. So what now? What are the components that may be at fault here?

I should point out that the car runs fine and I recently replaced the air filter.

Thanks,
Michael
95 e320 Wagon / 100K

you know what Ihave the same problem I have 95 e320 same code air injection mine doesnt have power going to the pump . I can not find the location of the air relay even I check the diagram something wrong the power goes pin 15 of the ECM such a headache Michell and all data their the same good luck to us hehehehe let me know if you find something...

[Arthur Dalton]

Check fuse 7