Air Injection System Issues

Discussion in '1994 - 1995 Specific Tech' started by sixt9coug, Jun 3, 2013.


  1. sixt9coug

    sixt9coug Member

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    First of all, the car does not have a CEL on or anything, and it overall is running well. It does ping when it gets up to operating temp however, and it also seems to idle a little higher when warm too. (around 700 as indicated on the tach when cold, 900 or so when warm).

    I've always noticed when I've had the car smogged that even though it's passed every time, it's always been on the dirtier side. It's never failed, but it's always been on the high side for certain limits. I have an OBD-1 scanner here at home and for the first time I decided to use it on the car.

    Well, it threw two codes. Both of them said that the air injection for left and right side was not operational.

    So I decided to take a look at it today and see what I could find. I took off the passenger wheel and fender liner and started poking around.

    - all of the lines look pretty solid. I did the propane test and saw no change in idle response from the engine.

    - I pulled off the lines one by one. All of the red lines were pulling vacuum.

    - I traced the lines up. None of the lines seemed to be pulling vacuum at their respective sources. The green, pink and orange(?) line did not seem to be pulling a vacuum at their sensors.

    - The red line was pulling a vacuum just fine, and the manifold source it was also pulling a vacuum.

    - I pulled off the line from the air pump and it was pushing air. I don't know how strong it's supposed to be, but there was a definite "puff-puff-puff-puff-puff" to it, but it wasn't exactly hurricane force.

    - I pulled smog pump line off after the cylinder head. It was weaker, but still steady rhythm.

    Now, I'm no expert as to how this whole system works, but where do I go from here to find out what's bad in the system? Would it be common for both under fender solenoids to fail? Is the pump the most likely culprit? What about the solenoids in the smog pump lines? Are those prone to failure too?

    If anyone has any other tests that might help narrow it down, I'd appreciate. I have to smog the car this September, so it would be nice to get this done before then. Also, I am under the assumption that the AIR also helps to cool the heads too right? Wouldn't that help my pinging as well? One can hope right?
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  2. sixt9coug

    sixt9coug Member

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  3. revhead347

    revhead347 I have face herpes.

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    Nobody here ever fixes that stuff. The pinging is more likely due to a dirty EGR valve.

    Kurt
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