After the actuator rebuild, the inde cleared all the codes old & new.
Next day, BAM!!! More codes. I'm nominating mine for "most code generator."

Any relationship between this new set?

Pin 1 Code 4 Air injection system faulty...

Pin 14 Code 7 CAN data bus signal ...

Pin 14 Code 11 Closed throttle recognition signal ...

Ironically the car runs great. It's just that pesky check engine light and it's PA inspection expires end of March.

Bob
A penny for your thoughts, I'm gonna need a bunch of them (pennies) to pay my inde!

AIR code can be tricky..the check is to make sure the pump runs and that the sov is allowing vac supply to the valve so the air can get pumped into the exhaust ports . If that is working,then you want to check the 02 sensor to see if it is still capable of a lean reading. That is how the ecu determines if the AIR system is working..it does a self test and looks at the 02 sens value to go real lean. A weak sensor that is not capable of a very low [lean] voltage will pop an AIR code even though the AIR system is working correctly.
The ecu electrical sig for the AIR sov is in parallel with the pump clutch, so if the pump is working, you know you have a sig to the sov.

Hi Arthur,

AIR code can be tricky..the check is to make sure the pump runs
___ Sounds & hums likes it ought to be working.
_____Clutch check - only moving when cold? Disengages when engine hot?

and that the sov is allowing vac supply to the valve so the air can get pumped into the exhaust ports .
___ That's one of the vacuum lines I didn't replace.

If that is working,then you want to check the 02 sensor to see if it is still capable of a lean reading.
___I have you instructions on how to do that.

That is how the ecu determines if the AIR system is working..it does a self test and looks at the 02 sens value to go real lean. A weak sensor that is not capable of a very low [lean] voltage will pop an AIR code even though the AIR system is working correctly.
___I've put about 40k on car, God only knows how old o2 sensor is.

The ecu electrical sig for the AIR sov is in parallel with the pump clutch, so if the pump is working, you know you have a sig to the sov.

Thanks
Bob

<>


Correct.
The vac hose going to the sov on 104s is plastic and they always dry up and break..it's under that front cover.......it's white

Did white one to sov from intake side.
Too cold to go outside with flashlight. So from memory something makes me think there's one from sov to air pump? If so I seem to remember it "disappearing" behind the pump. Or am I having vacuum confusion of the brain?
Bob

The one you replaced is engine common feed vac to the SOVs [egr and air ].
There are 2 coming out of the SOVs...one goes to egr and the other goes to the flow valve between the air pump and the engine. That is a vac actuated valve to allow the pumps air to reach the engine. If the pump runs , then you want to check that valve and see if vac is going to it .That would be the other vac line you are referring to and a disconnect here would be the cause of your AIR code. [ air not flowing to engine even though the pump does run] and thus, the 02 sens does not see lean and fails test, triggering air code/ce lamp.
There is also a final check valve at the engine to allow one-way checking of exhaust so it can't get back to pump. That is the whole system.
I have seen some AIR codes that where caused by guys putting the wrong connectors or vac lines on the sovs when re-installing after repair work, as they are a piggy-backed unit. If this is done , the egr is getting the air sig and the air is getting the egr sig. Might want to check that if all other things check out..
There is an article about it in the archieves by me or SB....

I thought testing the o2 "black" wire would be easy. Unfortunately, I have TWO. Which one do I test?

Or am I looking at the wrong wire harness in passenger foot well?
Thanks Bob
See attached pik.

Attached Thumbnails

 

The grn wire is 02 sig feed to ECU, so the other side of that plug is 02 sensor output.
The two whites are heater [12v.] and the other is ground.
You want to use the ground wire for neg. lead when testing 02 sens output
b/c they do not use chassis ground on 4 wire sensor with HFM/SFI systems...
best place to catch that neg is at terminal # 3 of the 3 prong connector..that will be the blk coming out of that connector...

Vac hoses are connected correctly at SVO with tight fit.

Hoses to Air Pump and to EGR are soft, pliable and orange (not OEM). Never could "see" where vac hose to Air Pump is connected. It's routed between the pump and block. Is "special mirror tool" used to see the connection? Pump is very quiet, but never have noticed a clutch engaging or disengaging.


Meter at 200mV, Engine hot and at idle.

Yesterday meter consistently fluctuated between 47 and 53 with both vac hoses connected and with one at a time disconnected.

Today meter consistently fluctuated between 18.2 and 21.5 with both vac hoses connected,
with hose to fuel regulator disconnected between 21.5 and 23.6 and with hose to SOV disconnected between 21.7 and 24.4

Are these vastly different (47-53 vs 18-24) readings correct or am I doing something incorrectly?

Considering my reading (if correct) is not near the .9 for Rich, can I assume the o2 sensor needs to be replaced?

Bob

<>

Pump clutch circuit needs testing.
Criteria for pump:
10C-40C coolant temp
less than 3600rpm
02 sens-open loop
Max run time from start -110 secs.

First check would be fuse/power feed
Second would be ohms test at clutch magnet coil.
The top sov is AIR and the AIR sov gets the same electrical signal as the pump, so if you take the vac line off the sov [after sov, betwen sov and control valve] and you have vac, you know that you have electric sig from ECU to both sov and pump , as they are wired in parallel. Meaning the pump should run at the same time the sov is open. Or you coud just 12v test lamp either the pump or sov..


I do not undestand your meter readings at all.

I do not undestand your meter readings at all.
___sorry about the decimal point (.47 - .53 vs .18 - .24) Undersand now?

Pump clutch circuit needs testing.
___ I'll do tonight after engine is cold

I gave fuse #7 a twist per your comment on another post & continunity is ok.

SOV question
Out of curosity I tested vac to SOV from intake manifold is 19, but vac to EGR and Air Pump were "0" @ idle & 80 deg engine temp. Is this correct?

Bob

< Out of curosity I tested vac to SOV from intake manifold is 19, but vac to EGR and Air Pump were "0" @ idle & 80 deg engine temp. Is this correct?
>>

You do mean 19" vac. . I assume.....and yes, there would be no vac flow to either under those temp/rpm conditions. EGR never comes on at Idle..it it did , it would stall/attemp stall the engine. And AIR will never come on at 02 closed loop or temp higher than 40C

Let me explain the SOV story. Sometimes if one knows what they are supposed to do, it is easier for the the guy working on it to see what is the problem. Vs. me saying check here for vac, then check there for sig , etc.

The vac from the manifold to the sov's [ both of them] is ALWAYS present with engine running. The SOVs SHARE this common feed from the engine
[ that is the white plastic line I mention that always breaks on 104s].
So, the sov has this constant vac supply at it's INTAKE PORT. [ notice these piggy back sovs have a 'Y' connector from the common feed hose ] Now, when the ECU wants one of these little valves to OPEN and allow this engine vac to go further down the line and do something [ like open and egr valve or an air pump valve, or a shift delay actuator, or whatever], it sends a 12 v. electrical sig to the sov solinoid. That opens that sov and allows the vac to flow OUT of the sov's OUT PORT. The valve is now in the OPEN position, ie, allowing flow.
So, you can see that an SOV is nothing more than a vac flow valve that is electrically operated.. [ in the trades , this is referred to as "elect over vac"
control. ]

So, when the engine wants the AIR system to activate, it sends an electric sig to the PUMP clutch [ energizing the pump] and at the same time , it sends the SOV the same 12v sig so that it can open , allowing vac to pass through it to the control valve that opens the AIR PUMPS output hose , [ this is the control valve between the pumps output hose and the engine..the one you are having trouble seeing b/c it is right behind the pump and hidden] which allows the pumps air to reach the exhaust ports for cyl 3 & 4 . That air combines with the rich exhaust and creates a very HOT , LEAN condition..which heats up the CAT real fast to deminish cold start-up emmissions. That is its sole design purpose. An Emmisiion Device to aide CAT in rapid warm-up.
So, If the pump does not come on [ as you suggests] , then I would be looking for the lack of an electrical sig to the pumps clutch magnet OR the ECU is sending a signal and the clutch is open/shorted and not responding to the sig.
How you test that is basic 12v test lamp, or vac output at sov, or ohm meter across clutch winding, etc.
It is very basic if you break down each component and know what each is supposed to do in the System
I think you kind know most of this anyway, but et al.............
Finally, the 02 sensor is just a test the ECU does for the Emmission Cops [CE]
If the 02 reports that it is not seeing a lean condition when it does a self test, it triggers the CE....but that simply means ANYTHING can be wrong in the AIR system..from no pump coming On to an sov not allowing flow , to a weak 02 sensor not able to see a lean condition, etc.........CE/AIR code does not specify a faulty PART, it detects a faulty SYSTEM only.
You will find the problem......

PS
Be aware that it is common practice for previous owners to unplug the pumps clutch connector and live with the CE.. take a peak there first.

<
Today meter consistently fluctuated between 18.2 and 21.5 with both vac hoses connected,
with hose to fuel regulator disconnected between 21.5 and 23.6 and with hose to SOV disconnected between 21.7 and 24.4

Are these vastly different (47-53 vs 18-24) readings correct or am I doing something incorrectly?

Considering my reading (if correct) is not near the .9 for Rich, can I assume the o2 sensor needs to be replaced?>>

These are the readings I an not sure about..the other without the decimal [47-53] I understand, but not these, as you have a decimal. [ 21.5 . 23.6, etc ??]

Anyway, a couple of pointers for you..
As you are using the engine for rich/lean generation, you MUST disconnect the green wire feed to the ECU or the ECU is going to try and correct your engine rich/lean inputs. Do you have the green wire still hooked up when testing the 02 output???
Also, you want to try these test at 2K.

Do you have the green wire still hooked up when testing the 02 output???
___Yes, I didn't know it was to be disconnected during test.

Also, you want to try these test at 2K.>
___I did it at idle.

No wonder I'm getting my forementioned voltage readings.

Thanks for "the SOV story." Now I can see the tree in the forest. I'm sure it'll help others as well.

I'll do the "fuse/power feed" test but I think I'll have my inde maniac do the other Pump clutch testing you mentioned.

Bob

OK........


...Before you go to Indie, you may want to make sure the pump clutch wire/connector is in fact, plugged in...

Good Luck