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Yes, you need to cut the flow between the intake and PCV.
 

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Discussion Starter · #43 · (Edited)
So, I took the test. Same symptoms.

However, new data.
I left for my test with "hot engine" at 90 °.
First launch in the RPMs, I was able to reach 5000 rpms and it started to have the usual vibrations / power losses.

On the return, it no longer exceeded 2800 laps, as on previous tests.

Next Step, find this "second vaccum tank (?)" Described in the subject I put just before.

To test my MAF or the throttle, do you have any ideas?

EDIT : When I unplug the MAF, I have an error code. After erase, no more code.
But does that mean it's just not being detected, not that it's sending bad data I guess

EDIT 2 : No second vaccum tank found. The hose go inside the car, driver side.
 

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Discussion Starter · #44 ·
I found this diagram.
Is it possible that a malfunction of G62 or G72 is causing my problems?

G 72 -
103148
103149
 

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I do not have a VR5 and haven't even seen one.
That small hose with a screw blocking it, should be connected somewhere. Check where the other end connects, that might give a clue.

To do the test suggested by PZ, you need to block all flow into the intake from that valve that you are pointing to in your 2nd pic.
I suggest you disconnect the hose from the LHS of that valve, and block the hose that connects to the intake.
 

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Maybe the air filter is restricting air flow.
Remove the air filter element and do a short test run.
 

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Your coolant sensor appeared to be working in the tests you posted. The intake air temps seemed to be as well as it was consistent with low speed (warmer) and high speed (cooler) driving.
 

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Discussion Starter · #48 · (Edited)
When stationary, when I accelerate up to 5000 rpm. I hear explosions in the exhaust. I think the air / fuel mixture is not good.
Still nothing when reading the calculator. For it "everything" is fine. Guess I can rule out malfunctioning elements from the previous image?

Diag Data :
RPM : 5221 / Load : 18,0 / Temp 90 / Air Temp 57 / air mass : 31.72g/s // Absolute Position of throttle : 23,5%
When I autocheck with my software these data, I have a message telling me that the absolute position of the throttle body was 0.8% inconsistent, could this have all of these consequences?

I forgot to specify that the car did not pass the anti-pollution tests that we have in France.

The car has an EGR.

EDIT : I may have found a clue with the crankshaft sensor - Apparently it can cause this type of error
 

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Does it get worse when you drive it longer? To the point of no power and lower rpm before stalling?
 

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Discussion Starter · #50 · (Edited)
Not at all, after the "failure" at 4500/5000 rpms the car no longer exceeds 2800 rpms, but if I drive below that limit, no problem driving "for a long time".
But I no longer have any power.

I found a used throttle body, I would try the change when I receive it. Yesterday I reconnected my solenoid valves, maybe a bad connection, I changed a hose which also seemed dead.
I will try during my lunch break.

EDIT : test fail - Next Step I ll change my Throttle body. :(
 

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Discussion Starter · #51 · (Edited)
Latest news, but unfortunately still not good.

I changed my Throttle body, all the same symptoms but no ECU errors.
The flowmeter values (heat and flow) appear to be correct, I have an ECU error when I unplug it.

I admit that I don't really know anymore.

While driving, I managed to hold the 2800 RPMs, when it is hot, it seems that we on / off its power every second.
Is the calculator that no longer works? Is there a trick to reset it?


I just reread my data records.

We agree that: Load value / Maf air flow are supposed to increase together?

On the table I put, there is an inconsistent reading. Column 3

Maybe if the MAF sends data going up and down, it causes these ON / OFF sensations that I have.

I will change it to remove this assumption.
 

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I would say it's the MAF only if the throttle always shows open (90% or so) when the problem occurs. Since it showed closed on that one test column, it throws off the possible MAF issue as an inconclusive test. Hopefully, you can figure it out as I don't know if it's the MAF or an ECU command for some odd reason.
 

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Discussion Starter · #53 · (Edited)
Do you think changing the MAF is useless? I can still cancel my order: p
When I unplug the MAF I still have the same symptoms and I have an error at the ECU...
Looks like the ECU is triggering a safe mode. But should I have error codes?


I still have solutions with the crankshaft and engine speed sensors...

But it's really strange that she manages to run it cold, but not once the normal temperature of the engine has been reached.
Could the heat from the engine cause another sensor to malfunction?
 

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I would at least try it, they are not real expensive. It's just very odd that the engine rpm will not climb, the air mass is low and the throttle opening is also low. Have you tried looking in the throttle with the engine off, but key on after the engine is hot and see if it opens properly?
The ECU can cut throttle for wheelspin, overheating, and maybe knocking.
 

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Discussion Starter · #55 · (Edited)
Hi PZ,

I found a sensor for the heat of the intake. It was full of oil, I cleaned it but still the same.

I just tried your idea, the throttle opens correctly and wide. I am going to buy sensors for RPM, crankshaft, MAF, heat and I think I will change the EGR.

I still have this hose, now disconnected, which goes into the driver side (but where ?). But the problems were the same before it was disconnected.
 

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Discussion Starter · #56 ·
Before buy lot of thing (maybe useless)
I used the VCDS test function on the engine ECU.

It turns out that all tests are conclusive except 2.

Gas recirculation: ok
Heating Lambda probe: ok
Lambda probe: ok
Air conditioning: ok
Secondary Air Injection: FAILURE
Evaporative Emissions: ok
Heating Catalyst: ok
Catalyst: FAILURE

What to think of these 2 failed tests?
My first question: does my car have sensors to test the catalyst and secondary air injection?

Still no error codes on the ECU
 

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The 1st O2 sensor checks the SAIP and the 2nd checks the CAT. When the SAIP runs, it pumps extra air into the exhaust and the ECU pumps extra fuel into the engine. This heats up the primary cat faster.

Is it possible you have the wiring for the 2 sensors swapped? That would screw up the air/fuel mixture. They are usally color coded from the factory, but replacements may not match.
 

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Discussion Starter · #58 · (Edited)
I think there is a serious clue here.

Indeed, the secondary air pump does not start at cold start (I found a completely broken hose).
However, during the VCDS "actuator" test, the pump runs fine.

This would mean that the ECU does not tell it to start for a cold starting.

I can't identify these sensors you're talking about.
The one that checks the CAT is the Lambda? If so, it is correctly detected and connected (and new).
Where should she be the SAIP sensor ?

When I test my EGR valve with a vacuum pump, I have resistance to pressure and suction. So is she OK?
I also hear a little "TAC" noise, the valve must be activated.

EDIT : SAIP is working again since I repaired the hoses. I will do a test today.
For my science, what produces vacuum on VR6 / V6 engines (VR5 is just a VR6 with one cylinder less)
 

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It has to be cold enough for the SAIP to activate. I don't know the exact temp range. I rarely heard mine run as it was often too warm here, even overnight.

The pistons moving down with the intake valve open is what creates vacuum. Later models added an electrical vacuum pump, usually near the ABS pump.
 

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Discussion Starter · #60 · (Edited)
Thank you PZ

And where should the SAIP probe be?
Here it is rather cold, and for reasons of fight against pollution, it should normally activate for all cold starts.

I guess my vacuum circuit is not good... but I find nothing about :(
 
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