Hi all, What would happen if I was to remove the soft hoses and seal the ends of the airbox, exhaust pipes and air intake box? Would the car still function properly? This is for a 87-328, and I live in a province in Canada that has no smog testing whatsoever. Regards
Try a search on "air injection nozzle" for prior threads about this issue (IMO, if you want to go this route, you should completely remove the whole system, including the manifolds and nozzles, so it can be preserved and kept and sold with the car -- there's a 99% chance it will still be here after you are long gone ).
On the 4Vs with Lambda control, they did a much better air injection nozzle design that doesn't obstruct the exhaust port so much, and sans belt-driven air pump (with a system that only operates during cold-running) they further lowered the HP loss, but things like the air injection manifolds, the hoses, cutoff valve, the check valves, etc., do keep getting "cooked" if left in place.
That is exactly why I want to remove the system and set it aside for future sale. It looks horrible in the engine bay, and everything in that system has got that burnt/tired look it. Regards
It will work, and that is because I have it that way. I only sealed the end of the tubes past the one way valves. I have to have the rest otherwise I fail smog inspection.
I plan on removing the sniffer tubes as well, they are broken at the manifold connectors, and I am presuming those are the reason my car is running really rich. Regards
Your sniffer tubes are post cylinder so why do you think they are causing a rich condition? Why do you think you are running rich?
You have a non-Lambda model (in your Profile) -- on those, you are right about a "post cylinder" exhaust leak not being a runability concern nor affecting the A/F ratio (but the noise and letting exhaust gas out where it shouldn't be let out isn't good), but, on a with-Lambda model like the OP's, a leak upstream of the O2 sensor can let extra O2 into the exhaust stream = the O2 sensor reports a "lean" signal = the Lambda ECU adds more fuel = too rich.
Exactly, Steve, Very well described A crack or a leak in the exhaust manifold is making the O2 sensor pick more O2 so it is telling the ECU that the mixture is too lean, resulting in your too rich condition. I think that it has gotten so rich that my O2 sensor is now fouled beyond repair and I need to replace it. But I am not going to until all my exhaust leaks upstream from the O2 sensor are sealed. Regards
Then how does the O2 Sensor account for the AIR system? Is it pre AIR nozzle? I thought that is why AIR systems were ditched in the first place. They are incompatible with the O2 sensor on fuel injected cars.
The air injection has a different function. It pumps air into the exhaust manifold to speed up burning of the hydrocarbons. That is regulated through a valve controlling the amount of air, and the O2 sensor accounts for that. My problem is that this sniffer tubes are broken (These are located further down the manifold, near the collector). As the exhaust gases is passing through the manifold, it creates, in essence, a venturi effect at the sniffer ports, which in turn sucks fresh air into the exhaust. The O2 reads this new, unregulated, uncontrolled mixture as lean. Regards
It doesn't. The air injection system on the K-Jet with Lambda F models only operates during cold-running (and the O2 sensor signal is not used during cold-running) -- the injection system runs "open-loop" like a non-Lambda system during cold-running (i.e., the signal going to the frequency valve is fixed to a constant default duty-cycle value). During warm-running, the cutoff valve closes, which seals the exhaust system off from the air injection system, and the O2 sensor signal is used by the injection ECU to actively control the frequency valve and run "closed-loop".
