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Discussion Starter #1
(2000 V6 ATQ)

Alright, so to pass inspection I had to dish out $$ to replace an O2 Sensor, Purge Valve, Breather Hose, and a Transmission Mount.

About a week ago I was driving behind my cousin who was making a U-Turn to get into a car wash. I also made the U-Turn and pulled up behind him. I admit, that I gave it a little too much gas, but nothing to make the tires screech.

As soon as I completed the turn, I felt my RMPs drop at idle below normal. To keep itself from stalling, the engine would rev itself up to ~1.5K RPMs, and then drop again to ~500 RPMs every 1.5 seconds. Between the RMPs dropping and the engine revving itself, you can hear the engine taking a breath (kinda sounds like a turbo). Rolling smoothly from a stop is nearly impossible, as I have to clutch in order to rev the engine, to keep it from jerking back and forth as the RMPs drop.

I had the car at this 'All German' shop (the same people that did my inspection and installed the above parts).

Upon scanning the yellow CEL for Emissions Workshop, 16 codes appear, which the shop probably doesn't have anymore. I'm going back wednesday morning, as the guy I wanted working on my car was on Vacation. My thought, is that a wire somewhere got lose coming out of the U-Turn, but they couldn't find it AFTER A WEEK w/ my car.

When I turn the car on now (which I haven't driven since that day), I can visibly see white smoke coming from under the air intake. I got under the car to try to find the culprit, but no luck.

I'm going to take the box apart and clean it, but what else should I be looking at? I suggested that they check the hoses, O2 Sensor, and all electronics, but they told me everything was good. They suggested changing the computer, but I simply don't see how this will change anything except for the balance in my bank account.

With all the problems I've had, I think the time is long overdue to start looking for a different car . . . .
 

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Discussion Starter #2
Any suggestions?
 

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If you had a bad motor or snub mount, the engine can hit the firewall. That may damage the intake snorkel or pull a vacuum line loose. I would also clean the throttle body as they get oiled up bad from the pcv system.
 

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Discussion Starter #4
I had a bad tranny mount. Thanks, I'll suggest that to the mechanic tomorrow morning.
 

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Discussion Starter #5
16 Codes:

P1425
P1472
P1435
P1530
P1421
P1121
P1117
P0102
P1115
P1119
P0134
P0154
P1114
P1140
P0140
P0160

Yay me.
 

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Discussion Starter #6
Okay, I looked everything up:

17833 P1425 Tank Vent.Valve Short to Ground
17880 P1472 EVAP Emission Contr.LDP Circ Short to Ground
17843 P1435 Sec.Air Inj.Sys.Pump Relay Circ. Short to ground
17938 P1530 Camshaft Control Circuit Short to ground
17829 P1421 Sec.Air Inj.Valve Circ Short to Ground
17529 P1121 O2 Sensor Heater Circ.,Bank2-Sensor2 Short to Ground
17525 P1117 O2 Sensor Heater Circ.,Bank1-Sensor2 Short to Ground
16486 P0102 Mass or Volume Air Flow Circ Low Input
17523 P1115 O2 Sensor Heater Circ.,Bank1-Sensor1 Short to Ground
17527 P1119 O2 Sensor Heater Circ.,Bank2-Sensor1 Short to Ground
16518 P0134 O2 Sensor Circ.,Bank1-Sensor1 No Activity Detected
16538 P0154 O2 Sensor Circ.,Bank2-Sensor1 No Activity Detected
17522 P1114 Bank1-Sensor2 Internal Resistant too High
17548 P1140 Bank2-Sensor2 Internal Resistance too High
16524 P0140 O2 Sensor Circ.,Bank1-Sensor2 No Activity Detected
16544 P0160 O2 Sensor Circ.,Bank2-Sensor2 No Activity Detected

I'm going to take a wild guess that they left a wire loose somewhere.
 

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Discussion Starter #7
STiLL NoTHiNg . . .
 

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Discussion Starter #8
Can someone find me where these wires would be located?
 

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The row of plugs behind the engine on the secondary firewall on each side of the engine. The harness runs across the back of the engine and under the coolant tank to the ecu.
 

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Does that look like the fuel pump relay issue they get on the jettas?
All those short to ground faults, I seem to recall something about just swapping out the fuel pump relay to clear them.
 

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Discussion Starter #11
Anyone happen to know if my engine would have a VIN number on it? I called VW and they said "only older models have the VIN # on the engine." . . .
 

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Discussion Starter #12
Still no car. This is the second time I had to go to school w/o my Passat.

I love the reliability of my car! :thumbdown
 

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Discussion Starter #14
No, but I'll call my mechanic and tell him to take a look ASAP, 'cuz this is bullshit how an all german car shop cannot figure this out for over three weeks now.

Have you had this problem before?
 

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Also, it fuse 29 is good, have mechanic check to see if he gets positive on the fuse when the key is in the start position. If no positive, it could be the fuel pump relay since a contact in the relay supplies the positive to the fuse.
 

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i havent had the time to dig into this the past week, so my car still has a CEL. A PW member emailed me specific details on how to trouble shoot for this problem.
Start by checking fuse 29 or 34 for yours and see if it blows when you start the car.
if it does email me and ill forward a copy.
Clear your codes with a scan tool. then Restart the car the CEL should come up within a few seconds when it does check the codes again. im willing to bet that the P14** codes will come up first. if they do it will cause all the other codes to come up also. they're all on the same circuit.

in short it could be
Secondary air injection pump relay
Secinadary air injection solenoid valve 25-35 ohms
fuel pump relay
Secondary air pump motor




so yeah PM me your email address.
 

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Discussion Starter #18
Is it possible that bad spark plugs + wires would cause all of this?
 

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PRoJeKV6 said:
Is it possible that bad spark plugs + wires would cause all of this?
No.
 

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Still troubleshooting this?

I've had some time to look at the wiring diagrams on this and I think I have some useful input for you. Here's what I have found...

There is one common wire supplying power to all those sensors/units that show up in those error codes and that power is supplied by Fuse 34 (As someone already mentioned). The supply of power comes from he fuel pump relay which is wired directly to the battery (un-fused) and sends power to fuse 34 (and a few others) when the ignition key is turned on (to the Start or Run position). After the power from that wire runs through each sensor/valve/ etc, those circuits are completed at the ECU. Which means the ECU controls the grounds to the various actuator/valves and the readings from the sensors. This does not neccesarily mean the ECU is bad, but since everything runs back through the ECU, that might be why your shop wanted to try replacing it.

You never did mention if the fuse was actually blowing or not...

It could actually be a number of things...
If fuse 34 is blown (and continues to blow after being replaced), either the Grn/Yel wire from fuse 34 is shorting out on the chassis or something OR you could have a bad sensor or adjustment valve in any one of those units listed in your error codes. If even one unit is bad and is shorting out, it will effect all the others as well and will throw up all those codes since it runs off the same circuit.

If the fuse doesn't blow then the short could be before the fuse, but I doubt your car would run at all because the power to the fuel pump would short out too. (no fuel = no run!) If your fuse is good, I'd be inclined to blame the fuel pump relay or your ECU.



From your list of error codes I'll assume fuse 34 is blown.
Here's a list of all the items you shop needs to check.

O2 Sensors (all four)
Mass Airflow sensor
EVAP Emission canaster purge regulator valve
Secondary Air Injection Solenoid Valve
Secondary Air Injection Pump Relay
Intake Manifold change-over valve
Camshaft Adjustment Valve 1
Camshaft Adjustment Valve 2


OK, so you/they probably could have figured that out with the list of error codes. But you need to do two things. Disconnect the electrical connector and check the terminal on each item (not the harness) that corresponds to the GRN/YEL wire for a "short to ground". If you find one, you know what to replace. If no short is found on the items listed, you need to disconnect ALL of them and check the wiring harness for a short to ground.

The only other thing I can think of is to keep clearing codes, remove the connector to one item at a time, and start the car. If you get all the same codes you go before then the one you disconnected is fine and something else is throwing it off. When/if you disconnect a bad one, the short would be removed so only the item you disconnected will return an errof code. Not very scientific, but another option at the least. Only problem is I don't know how long it might take the codes to appear so this could be a very time consuming process.


A good mechanic should know how to check each item in that list to make sure it's working, and also how to check for a short to ground in the wiring harness.

Last option would be to try switching the ECU with a known good one. If you get the same problems (error codes) you were having before then don't waste your money buying a new one.



That's all I can come up with at the moment. I hope something works!!
I know (INTIMATELY) what a bummer it is to have a car not working right! :(
If I can help in any way, let me know.
 
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