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Discussion Starter · #1 ·
On a warm day when secondary fan comes on vehicle looses power and runs like i am pulling a trailer. Is this normal or do i need colder spark plugs for more power. 2001 V6 passat 88,000 miles new plugs at 60 thousand.
 

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No CEL or code(s)? Obviously something electrical. Would not be plugs, but the fan motor/circuit could be causing a system-wide voltage drop (spark and fuel pump affected).

Electrical gurus can jump in here.
 

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Not something I would normally attribute big time power loss to, but my wife's V6 GLX had a faulty (a/c condenser) fan. It would spin up but not fast enough thus not cooling the a/c system enough for it to work properly. Would actually start to blow hot air through the vents. When this happens the a/c compressor starts slug. So much so it can kill the engine.
 

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Discussion Starter · #5 ·
Not something I would normally attribute big time power loss to, but my wife's V6 GLX had a faulty (a/c condenser) fan. It would spin up but not fast enough thus not cooling the a/c system enough for it to work properly. Would actually start to blow hot air through the vents. When this happens the a/c compressor starts slug. So much so it can kill the engine.
AC was off!
 

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Obviously something electrical. Would not be plugs, but the fan motor/circuit could be causing a system-wide voltage drop (spark and fuel pump affected).
Yes, forget the plugs. Plus, a "colder" plug doesn't increase the engine's power. If fuel or spark malfunctions due to the fan turning on, I'd suspect corroded electrical grounds.
 

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If your secondary fan is coming on without the a/c, I hope you have been watching the temp gauge. It sounds like the car is overheating and pulling timing.
 
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Discussion Starter · #9 ·
If your secondary fan is coming on without the a/c, I hope you have been watching the temp gauge. It sounds like the car is overheating and pulling timing.
If the guage works it us running in the middle as it has since day 1 180 degrees. Checked codes today again after coming home it idled rough but no codes still getting 30mpg average on 91 octane. 88,000 miles on car! Maybe spark plug wires or a coil breaking down when getting hot after driving.
 

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What scanner are you using, is it a decent VAG scanner such as VCDS ?
Did you do a full scan of all modules ?

Have you noticed any other issues, do the lights lose brightness, do any of the wheels get hot ?
 

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I used a innova and my sons Konnwei!.
Tomvw said:
1: "What scanner are you using, is it a decent VAG scanner such as VCDS ?
2: Did you do a full scan of all modules ?

3: Have you noticed any other issues, 4: do the lights lose brightness, 5: do any of the wheels get hot ?"

I went to the trouble of devising 5 questions, trying to help you; and you only bothered to answer one of them.
All I ask of you, is that you try to help yourself. If you can't be bothered why should I ?

If the plug wires or coils were breaking down, any OBDII scanner should report the miss-fires.
A scan of all modules with VCDS would be helpful.
 

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Discussion Starter · #13 ·
Tomvw said:
1: "What scanner are you using, is it a decent VAG scanner such as VCDS ?
2: Did you do a full scan of all modules ?

3: Have you noticed any other issues, 4: do the lights lose brightness, 5: do any of the wheels get hot ?"

I went to the trouble of devising 5 questions, trying to help you; and you only bothered to answer one of them.
All I ask of you, is that you try to help yourself. If you can't be bothered why should I ?

If the plug wires or coils were breaking down, any OBDII scanner should report the miss-fires.
A scan of all modules with VCDS would be helpful.
Thanks no lights dim, Wheels getting hot i will thermal next ride! Could not do full scan of modules.I really accept your input and sorry for any items i missed!
 

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Clean MAF sensor where? How
Look up passat maf replacement on YouTube. There is video on how to get to the maf sensor. It's a little work but easier than it looks. It recommends replacement if you are gonna take it out, but I just cleaned it with some maf cleaner from auto zone and put it back in and solved the problem
 

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I think you really need to get it scanned with VCDS or other good VAG specific scanner.

Did you know you can get a cable for about $10 - $20 and VCDS :Lite free.
For about $10 to $20 get a 409.1 VAG cable from Amazon or eBay, the disc that came with mine had viruses, don’t use the disc.
Download VCDS Lite (FREE) and install in Windows. Ross-Tech: Home
$99 for registration if required for easier operation, the free version will read all codes from all modules.
Download USB-Com Port driver (VCP) and install in Windows. Drivers - FTDI
 

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I think you really need to get it scanned with VCDS or other good VAG specific scanner.

Did you know you can get a cable for about $10 - $20 and VCDS :Lite free.
For about $10 to $20 get a 409.1 VAG cable from Amazon or eBay, the disc that came with mine had viruses, don’t use the disc.
Download VCDS Lite (FREE) and install in Windows. Ross-Tech: Home
$99 for registration if required for easier operation, the free version will read all codes from all modules.
Download USB-Com Port driver (VCP) and install in Windows. Drivers - FTDI
Thanks for info!
 
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