# 2002 passat 30V intermittent slow start



## scottp (Aug 13, 2007)

Hello, I have an 02 passat with the 30 valve V6. Sometimes it takes a long crank to start up. It doesn't metter if it is hot or cold. It is frustrating because it starts up very fast and others super slow. Has anyone came across this problem? Thanks!


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## strapagosse (Mar 25, 2006)

*Re: 2002 passat 30V intermittent slow start (scottp)*

Check your satring system : battery, starter.


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## scottp (Aug 13, 2007)

*Re: 2002 passat 30V intermittent slow start (strapagosse)*

sorry for my lack of detail. It cranks fast. It isin't fule pressure. what do you think?


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## strapagosse (Mar 25, 2006)

*Re: 2002 passat 30V intermittent slow start (scottp)*

Did you had any repair done recently? Did you scan your car for DTCs?? That would be a good starting point.


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## scottp (Aug 13, 2007)

*Re: 2002 passat 30V intermittent slow start (strapagosse)*

no work done, I do need an air pump thou. what do you think?


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## strapagosse (Mar 25, 2006)

*Re: 2002 passat 30V intermittent slow start (scottp)*

What's wrong with your air pump?
Like I said before, you need to get it scanned. I think it would be the first step in your case. I don't wanna send you on the wrong paths because of missing informations.
You could have bad fuel (contaminated with water for example, it's relatively common).
Bad residual fuel pressure.
Starter that doesn't crank fast enough (though it's more frequent on TDI engines)
Bad t-belt timing.
Faulty cam sensor.
Etc etc the list goes on....


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## scottp (Aug 13, 2007)

*Re: 2002 passat 30V intermittent slow start (strapagosse)*

I have a code reader, only secondary air pump code comes up. I don't think it is bad gas since it has been this way for about 2 months. The starter sounds like it is cranking fast like a toyota. It has a great battery. what is resedual fuel pressure?


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## strapagosse (Mar 25, 2006)

*Re: 2002 passat 30V intermittent slow start (scottp)*

When you turn off your engine, the fuel pump stops, your fuel pressure also drops since the pump is now inactive. There is a valve inside the pump that prevents the pressure in the lines to drop below a certain point. If your pressure drops to zero, it will take a longer crank to start the engine because the fuel pump will have to "rebuild" the pressure.
So, residual fuel pressure is the pressure that's maintained in your fuel lines to help engine start.
You can check it by hooking a fuel pressure gauge to your car. You start your engine and check your fuel pressure if it's within specs, then you turn the engine off and check for sudden drop. It should drop down slowly to a certain point (i don't remember what the spec is for this engine, i'll have to check). Usually you have to leave the fuel pressure connected until the next morning to see if the pressure dropped too low.


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## scottp (Aug 13, 2007)

*Re: 2002 passat 30V intermittent slow start (strapagosse)*

that would be great if that was the problem. I'll buy a pressure guage and see. I've always wanted one. Thanks!


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