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  • #46
    Glad to hear you got another MAF sir. Did the MAF code return?

    Perhaps it is running smoother, but only you can really tell. However the only way to reduce the fuel pressure at idle is to apply maximum vacuum to the FPR. You need to find those leaks and apply that vacuum. Nothing else in the entire injection system can compensate for that missing vacuum. So yes, until you can get 18 inHg to the FPR, you will be running rich.

    While you are waiting, you may want to test the old CTS in hot water, it is simply a good practice to always prove your components when you can. Same with the new one, rather than just buy, install and wonder if the new one will function correctly, when you can prove both of them and know they should work. If the old one is fine, you can keep the new one new; as a spare. Because as others have mentioned above, both the wiring and connector itself (just like it says in the list of possible faults in the fault codes) for these components can also be at fault besides the component itself.

    Trouble-shooting is a bit like solving a crime, in that one has to do all the dull leg-work to gather evidence, explore leads, eliminate false trails and finally prove your case. That is the "prove" in making an improvement.

    Comment


    • #47
      Originally posted by Lago Blue View Post
      Glad to hear you got another MAF sir. Did the MAF code return?

      Perhaps it is running smoother, but only you can really tell. However the only way to reduce the fuel pressure at idle is to apply maximum vacuum to the FPR. You need to find those leaks and apply that vacuum. Nothing else in the entire injection system can compensate for that missing vacuum. So yes, until you can get 18 inHg to the FPR, you will be running rich.

      While you are waiting, you may want to test the old CTS in hot water, it is simply a good practice to always prove your components when you can. Same with the new one, rather than just buy, install and wonder if the new one will function correctly, when you can prove both of them and know they should work. If the old one is fine, you can keep the new one new; as a spare. Because as others have mentioned above, both the wiring and connector itself (just like it says in the list of possible faults in the fault codes) for these components can also be at fault besides the component itself.

      Trouble-shooting is a bit like solving a crime, in that one has to do all the dull leg-work to gather evidence, explore leads, eliminate false trails and finally prove your case. That is the "prove" in making an improvement.

      the code is gone now, i tested the car with only the vacuum tester on the tube 3 on the picture and than i got about the 18 inHG with cold engine. i had connected the system like i draw in the picture. but i think its not good. 1 is the thin tube from the carter breather, number 2 is closed. number 3 connection on the inlet manifold. number 4 on the cylinderhead, fpr: Fuel Pressure regulator. if this is good there is another problem. if this is not good can you draw or say how i can connect it. i only use the Fuel Pressure regulator with the vacuum system. when it is connected to the cylinder head and carterbreather there is a open connection to the air filter and leaking my vacuum right? or do i need to make the carter breather to the cylinder head and put the FPR to the intake manifold?

      greetings Mike

      Comment


      • #48
        Two systems - one connection

        Very good sir! About 18 inHg cold is at least something you can start to work with!

        Please explain why you are not allowing the engine to warm up? Waiting for new CTS, correct? BTW, did you hot-water test your coolant thermostat before its' install?

        I think your suspicion about your hose's hook-up as per your drwg., is correct. I also think your very last sentence (beginning "or do I need to...") above is the correct course to follow, as follows:

        a) Look again at the Crank-case Vent (CCV) or a.k.a.: the Breather System diagram below (I have added the intended flow directions with blue arrows), note there is -no- connection to the FPR, and:

        - see how it only connects to the Vacuum System at one point, right at the I/M (in your drwg., via I/M vacuum port #3) and note it does that via the short line with the 1mm ID restrictor; to the large CCV hose. You need to do the same. That necessary restrictor ensures (given a well-sealed crankcase - which you may not yet have!) and only allows a very small limited "draw" on the engine vacuum, small enough that you should still have 18 inHG in the I/M at warm idle to supply the FPR with, and with the CCV hooked up as per the diagram below.

        - It sounds (re: "1 is the thin tube from the carter breather") as though your car may indeed have had (exactly as per the diagram below) the early car's "siamesed" two-hose version of the CCV hose arrangement (one larger O.D. figure "3"-shaped hose; plus one small O.D. "?"-shaped hose, and both join up down near the engine block's main CCV connection down below on its' lower LH side). You may need to copy that CCV arrangement exactly as per the below diagram if not already present. In either case your small #1 hose should only connect to your port #4 alone and nothing else (save for the larger CCV hose at it's other end).

        Early 7A CCV System Drwg 1 with intended flow direction indicated.png

        Audi 7A early CCV System description.png

        b) There should not be as you say "...there is a open connection to the air filter and leaking my vacuum right?". No, not quite, there may be an open connection, but not to the air filter. There is no use for vacuum at the air-filter box area (unless your car had an EGR like the California versions), so no hose need go there. Look again at the vac. diagram below:

        Audi 7A engine compartment vacuum system lay-out drwg.png

        What may be happening when hooked-up as per your drwg., is that something is still open/leaking in the CCV system. Both systems should best be closed.
        Last edited by Lago Blue; 26th July 2020, 02:06.

        Comment


        • #49
          Originally posted by Lago Blue View Post
          Two systems - one connection

          Very good sir! About 18 inHg cold is at least something you can start to work with!

          Please explain why you are not allowing the engine to warm up? Waiting for new CTS, correct? BTW, did you hot-water test your coolant thermostat before its' install?

          I think your suspicion about your hose's hook-up as per your drwg., is correct. I also think your very last sentence (beginning "or do I need to...") above is the correct course to follow, as follows:

          a) Look again at the Crank-case Vent (CCV) or a.k.a.: the Breather System diagram below (I have added the intended flow directions with blue arrows), note there is -no- connection to the FPR, and:

          - see how it only connects to the Vacuum System at one point, right at the I/M (in your drwg., via I/M vacuum port #3) and note it does that via the short line with the 1mm ID restrictor; to the large CCV hose. You need to do the same. That necessary restrictor ensures (given a well-sealed crankcase - which you may not yet have!) and only allows a very small limited "draw" on the engine vacuum, small enough that you should still have 18 inHG in the I/M at warm idle to supply the FPR with, and with the CCV hooked up as per the diagram below.

          - It sounds (re: "1 is the thin tube from the carter breather") as though your car may indeed have had (exactly as per the diagram below) the early car's "siamesed" two-hose version of the CCV hose arrangement (one larger O.D. figure "3"-shaped hose; plus one small O.D. "?"-shaped hose, and both join up down near the engine block's main CCV connection down below on its' lower LH side). You may need to copy that CCV arrangement exactly as per the below diagram if not already present. In either case your small #1 hose should only connect to your port #4 alone and nothing else (save for the larger CCV hose at it's other end).

          Early 7A CCV System Drwg 1 with intended flow direction indicated.png

          Audi 7A early CCV System description.png

          b) There should not be as you say "...there is a open connection to the air filter and leaking my vacuum right?". No, not quite, there may be an open connection, but not to the air filter. There is no use for vacuum at the air-filter box area (unless your car had an EGR like the California versions), so no hose need go there. Look again at the vac. diagram below:

          Audi 7A engine compartment vacuum system lay-out drwg.png

          What may be happening when hooked-up as per your drwg., is that something is still open/leaking in the CCV system. Both systems should best be closed.

          i looked at your schematics, only here is a resistence on the tube that goes from the crankcase breather to the rubber tube for the throttle body. only there is no connection for this on the pipe. is this tube a newer model?

          why I do not let the car get warm is because there is no coolant in the car and it otherwise the engine damage. the sensor is not there yet.

          the thermostat has been tested and works properly and opens at the correct temp.

          this car had no egr system.

          1 connection: nr3 going to the FPR and 1 connection: Nr2 going to the big connection on the Carter breather right? At my previous message i sayed something about the leaking to the filters but i mean if the connection nr 3 connect to the Carter breather and going into the rubber tube before the throttlebody the vacuüm is leaking ? There is no vacuüm at that 90degrees hose while throttlebody is close?


          Tube number from Carterbreather: 054103211c

          Comment


          • #50
            Mike,

            Here again is a link to view the various P/N's for the 7A CCV system (note the illustration is for a 10V motor, but the numbers for the different 7A versions appear to be there, it even lists the diameters and lengths of some of the hoses!):

            https://audi.7zap.com/en/rdw/audi+co.../1/103-103085/

            Question: I don't see your P/N: "054103211c" listed there. Is this for a 7A? However, I have seen it listed for some newer vehicles.

            To your questions in your last paragraph:

            a) Yes, one connection from your #3 to the FPR would be correct (your diff lock and fuel tank vent systems are not operable, correct?).

            b) No, if you connect your #2 directly to the CCV system, that is not correct. That would apply full vacuum to the CCV, which you should not want. As we only want a very limited vacuum supply to the CCV, so we must use the required restrictor or "choke" in that connection.

            The CCV system will have two "resistances" in it when properly complete, the above mentioned #17 choke (or #17a? See in the 7Zap link above) which is the same 1mm restrictor I've mentioned previously, and the #23 the flame deflector plate in the long larger I.D. tube / hose assembly #11 which PeterS mentioned back at post #12 and you may already have and be describing in your sentence "only here is a resistance on the tube that goes from the crankcase breather to the rubber tube for the throttle body.", correct?

            - The #17 restrictor / choke goes between your tube / hose assembly #11 and your #2 vacuum port at the I/M;
            - The #23 flame deflector plate is in that same #11 assembly above, but down closer to the block vent; and
            - Your #11 assembly (via fittings 8A and 8E, see at 7Zap) should also connect to your #4 head port with a small I.D. hose.

            c) Yes, the vacuum is leaking, and that is our specific intent here. However, because we will include the required 1mm restrictor (or "choke") in the CCV connection to your #2 vacuum port on the I/M, we will have restored the original Audi-designed small vacuum "leak" to our properly "closed" CCV system, and yes that will pull air from "the rubber tube before the throttle-body", but because that air volume will be minor due to the small opening in the restrictor, and it will have been metered by the MAF and compensated for by the ICS, we don't care! Clever those Germans.

            The above necessary vacuum bleed or "leak" is one of the reasons all our other vacuum connections must be leak-free, to ensure we still have the maximum vacuum available to apply to the FPR. Another would be to allow the ICS to operate well within its' range.

            d) No, "There is no vacuüm at that 90 degrees hose while throttle-body is closed", correct sir. The purpose of this connection is, as PeterS stated back at post #12 "...it is designed to allow crankcase fumes to be re-entered into the engine for combustion." when not at idle. At larger throttle openings can be when the most crankcase pressure is made, so we need to best re-introduce it back into the engine. To the last sentence in the blue text box in my last post above, I will add the bracketed phrase: "When the throttle is opened (hence there is no longer any vacuum), crankcase fumes will also be drawn in through the intake air boot". That is why we must also have that larger hose #11 as a second reasonably sealed fume disposal connection ahead of the throttle-body (perhaps still currently plugged shut in your 90 degree rubber boot, correct?).
            Last edited by Lago Blue; 2nd August 2020, 22:14.

            Comment


            • #51
              Originally posted by Lago Blue View Post
              Mike,

              Here again is a link to view the various P/N's for the 7A CCV system (note the illustration is for a 10V motor, but the numbers for the different 7A versions appear to be there, it even lists the diameters and lengths of some of the hoses!):

              https://audi.7zap.com/en/rdw/audi+co.../1/103-103085/

              Question: I don't see your P/N: "054103211c" listed there. Is this for a 7A? However, I have seen it listed for some newer vehicles.

              To your questions in your last paragraph:

              a) Yes, one connection from your #3 to the FPR would be correct (your diff lock and fuel tank vent systems are not operable, correct?).

              b) No, if you connect your #2 directly to the CCV system, that is not correct. That would apply full vacuum to the CCV, which you should not want. As we only want a very limited vacuum supply to the CCV, so we must use a required restrictor or "choke" in that connection.

              The CCV system will have two "resistances" in it when properly complete, the above mentioned #17 choke (or #17a? See in the 7Zap link above) which is the same 1mm restrictor I've mentioned previously, and the #23 the flame deflector plate in the long larger I.D. tube / hose assembly #11 which PeterS mentioned back at post #12 and you may already have and be describing in your sentence "only here is a resistance on the tube that goes from the crankcase breather to the rubber tube for the throttle body.", correct?

              - The #17 restrictor / choke goes between your tube / hose assembly #11 and your #2 vacuum port at the I/M;
              - The #23 flame deflector plate is in that same #11 assembly above, but down closer to the block vent; and
              - Your #11 assembly (via fittings 8A and 8E, see at 7Zap) should also connect to your #4 head port with a small I.D. hose.

              c) Yes, the vacuum is leaking, and that is our specific intent here. However, because we will include the required 1mm restrictor (or "choke") in the CCV connection to your #2 vacuum port on the I/M, we will have restored the original Audi-designed small vacuum "leak" to our properly "closed" CCV system, and yes that will pull air from "the rubber tube before the throttle-body", but because that air volume will be minor due to the small opening in the restrictor, and it will have been metered by the MAF and compensated for by the ICS, we don't care! Clever those Germans.

              The above necessary vacuum bleed or "leak" is one of the reasons all our other vacuum connections must be leak-free, to ensure we still have the maximum vacuum available to apply to the FPR. Another would be to allow the ICS to operate well within its' range.

              d) No, "There is no vacuüm at that 90 degrees hose while throttle-body is closed", correct sir. The purpose of this connection is, as PeterS stated back at post #12 "...it is designed to allow crankcase fumes to be re-entered into the engine for combustion." when not at idle. At larger throttle openings can be when the most crankcase pressure is made, so we need to best re-introduce it back into the engine. To the last sentence in the blue text box in my last post above, I will add the bracketed phrase: "When the throttle is opened (hence there is no longer any vacuum), crankcase fumes will also be drawn in through the intake air boot". That is why we must also have that larger hose #11 as a second reasonably sealed fume disposal connection ahead of the throttle-body (perhaps still currently plugged shut in your 90 degree rubber boot, correct?).

              good evening,
              i have bad news when it comes to the idle problem. I connected all the snakes as on the schedule and as you told me. only the stationary vacuum at 15inhg (this may also be due to the low idle speed) I added a 1mm resistor just like in the drawing. new spark plugs mounted. Run engine warm but idle still runs poorly and still fluctuates at 50 rpm. when the engine is idling. do you hear a sucking sound through the power filter is this because the throttle does not close properly or is this the bypass that you can set with the screw? I also ran the engine to learn the new MAF and to adjust itself. but this has no effect. I don't know what to do with it.

              Comment


              • #52
                Does the 7A have a PCV system? Maybe a leak in that?
                O ring missing from dipstick?
                Oil filler cap not closing?

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                • #53
                  Evening Mike,

                  Alright, let us step back and perhaps undo what you have changed; one step at a time.

                  This would also be a good time to mention that as a general rule, when making changes, one should limit the number of changes in between testing; to one. This allows one to immediately make the connection between which effect resulted from exactly what cause.

                  Questions:

                  a) C/T sensor and coolant are back in, correct?

                  b) Since you replaced the O-ring in throttle-body, you have not changed the bypass screw, correct?

                  c) Currently, warm vacuum is now lower, and idle is perhaps approx. 500(?) and fluctuating, correct?

                  d) You hear a new sucking sound heard from the air filter, correct?

                  Perhaps next try blocking the connection of the I/M to the CCV (connects via the 1mm restrictor); and see / listen if the sucking sound stops when that engine vacuum bleed is closed.

                  Comment


                  • #54
                    Mike,

                    Newsh is exactly right I believe, (and that is where I was going to send you next) but I wanted to give you the chance for the joy of self-discovery; first!

                    Comment


                    • #55
                      Originally posted by Lago Blue View Post
                      Evening Mike,

                      Alright, let us step back and perhaps undo what you have changed; one step at a time.

                      This would also be a good time to mention that as a general rule, when making changes, one should limit the number of changes in between testing; to one. This allows one to immediately make the connection between which effect resulted from exactly what cause.

                      Questions:

                      a) C/T sensor and coolant are back in, correct?

                      b) Since you replaced the O-ring in throttle-body, you have not changed the bypass screw, correct?

                      c) Currently, warm vacuum is now lower, and idle is perhaps approx. 500(?) and fluctuating, correct?

                      d) You hear a new sucking sound heard from the air filter, correct?

                      Perhaps next try blocking the connection of the I/M to the CCV (connects via the 1mm restrictor); and see / listen if the sucking sound stops when that engine vacuum bleed is closed.
                      hello, Yes the coolant sensor and the c/t sensor are back.

                      I removed the screw and than changed the o-ring and place the screw back in it.

                      The idle is about the 600 rpm and fluctuating with 100 to 50 rpm.

                      Yes that sucking sounds was not before.

                      I have block the pipe that comes from the intake manifold and going into the carter breather but it give no response. the sound is not stops

                      I have made a video so you can hear the sucking sound. Link: https://www.youtube.com/watch?v=OetykuldyTk


                      Also checked the fault codes again and there are now some more faults. I can comes from removing the connectors and place them back? I got the next fault codes:

                      2232: fault from MAF
                      2114: Ignition distrubitor basic
                      2212: Throttle valve position
                      4431: Idle stabilizer valve

                      All the connectors between this components are connected. but the cables that go into the MAF sensor has been hot and the cables have fused together, I'm not sure if the copper cables are touching but I don't think so. shall I solder a new piece in between the MAF and the cabletree?

                      also checked the o ring from the dipstick and its still on there. the oil filter is new and closed great. and there is no PCV system on this engine.


                      Greetings Mike

                      Comment


                      • #56
                        How are you measuring idle speed? The dash tacho is NOT accurate, and it sounds way too low.

                        The sucking noise from the air filter is entirely normal, after all, that is what the engine is doing.

                        Comment


                        • #57
                          Originally posted by Bowie69 View Post
                          How are you measuring idle speed? The dash tacho is NOT accurate, and it sounds way too low.

                          The sucking noise from the air filter is entirely normal, after all, that is what the engine is doing.
                          Hello, incheck the idle speed with a ignition light. This light have a led display that tell the engine speed. It is fluctuating Round the 600rpm(+- 100rpm) how can i get a higher rpm at idle ? The screw is almost at the end.

                          Comment


                          • #58
                            Perhaps the throttle body idle screw is gummed up then, and it not allowing you to open it up any further?

                            You could take it off and clean it all out with carb/brake cleaner, easy job and not too time consuming.

                            Comment


                            • #59
                              Originally posted by Bowie69 View Post
                              Perhaps the throttle body idle screw is gummed up then, and it not allowing you to open it up any further?

                              You could take it off and clean it all out with carb/brake cleaner, easy job and not too time consuming.
                              I have clean the throttlebody but no response the same problems, but What about the fault codes ?

                              Comment


                              • #60
                                Mike,

                                You may be correct about the cause of the fault codes, did you disconnect all of those 4 items?

                                You could next try erasing the codes; and then see which return.

                                Q: - When you say "...the oil filter is new and closed great.", you meant the oil filler cap on top of the cam-cover, correct?

                                Q: - What is the fully warm idle vacuum now?

                                I saw your video, and:

                                Q: - Did you adjust the "idle air screw" out in attempting to raise the idle speed? Did it help at all?

                                Q: - When you cleaned the T/B, did you confirm that the two(?) small drilled air passages on either side of the throttle-blade which connect to the idle air screw passage; where in fact fully clear?

                                Q: - Is the O-ring for the replacement MAF sensor itself present and in good shape?

                                Q: - When was that air-cleaner last cleaned or replaced? Is it the type that requires oil?

                                Q: - Did you try disconnecting the ISV at full warm idle and noting what happens?

                                Q: - Because your engine appears to vibrate a good deal and idle slow, is it possible that one cylinder is not firing? (600 rpm divided by 4 cyl = 150 rpm. 150 + 600 would be 750 which is right where you'd want to be as a minimum). Perhaps try disconnecting each spark-plug one at a time to ensure all cylinders are working.

                                Q: - In your post #36 on page 3 above, you say "...and the other line go to the Idle Switch.", however there should be no such vacuum line or any place for it to connect to there. What did you mean?

                                Last edited by Lago Blue; 5th August 2020, 00:13.

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