93 Jetta Starting Problems, Not a car person

[zechirian]

Heya all,

Just came into a 93 Jetta, and I don't really know much at all about the inner workings of the car. Its an automatic, 4 banger. Has about 140k miles on it.

Problem:
After letting the car sit for about 6 hours or so it has a hard time starting up. I can turn the key and it will sound like its trying to start (doesn't sound like its turning over, just like its trying to turn over), after about 10 seconds it sounds like it truns over once or twice then sputters out. Usually on the second try about 8 seconds into holding the key on START it fires up with a little puttering and then its just fine as can be, sounds normal, revs just fine, doesn't die while driving. It's only have leaving it sit for 6 hours or so that it decides it wants to be stubborn.

I don't know how to test gauges and all that stuff so its gunna have to be in the most lamen of terms if you please .

To me it sounds like something with the gas line but I don't under stand that its just fine after you've got it started... maybe vacuum or something?

Please help If you want to know something specific please ask as this is the best i can do right now

[Doug Tatham]

Have someone check your fuel pressure. It sounds to me like you have a fuel pump that is getting ready to die.

[zechirian]

Does the gas pump make a noise of some kind when you turn the car on? Also could it possibly be a filter??

[Doug Tatham]

When you first turn the key the gas pump goes for a couple seconds. It could be the gas filter. Check to see if an autoparts store nearby will check your fuel pressure.

[whiteso]

When replacing the fuel filter instructions say to release fuel system pressure before starting. Any Idea on how to do that?

[Doug Tatham]

There is a check valve on the suction side of the fuel pump. See if it's either faulty or dirty. It sounds like the fuel is slowly draining back into your tank when the engine is shut off for awhile. Also check to see if you have any fuel line leaks. As stated earlier, fuel pressure would be a place to start. You may also disconnect the fuel line from the fuel rail and hook a clear tube to it and run it into a gas can (grounded!), disconnect the ignition from the starter and have someone turn the key to make the pump operate. Watch to see if you are getting some air prior to gas flow.

Releasing fuel pressure: Remove the fuse for the fuel pump. Start engine and let it run until it stalls out. Remove the keys and replace fuse. You'll need to turn the key for a few minutes before it starts the next time. Don't turn on the ignition until finished replacing the filter.

[zechirian]

Ok well i got a chance to drive it for a while yesterday and while in normal gear D it sputters unless your accelerating then its fine. Starting off the line and cruising it real putters and bucks but as soon as you hit the gas its fine. Also i notice if i put it in 3rd gear its just fine.. no bucking, no sputtering, cruises just fine. Starting off the line it hesitates a little bit but nothing like D does.

Can autozone test the fuel pressure?

[Doug Tatham]

I don't know if Autozone will or not. It's easy to do and jsut takes a couple seconds, so I wouldn't be surprised if they do. They may not though because of liability, it's possible (though extremely unlikely) that they may spray gas all over the place and start a fire. A lot of people don't like to touch anything involved with flamable liquids.
Regardless, it sounds like you have a problem with fuel pressure and you could end up stranded if your fuel pump goes out completely. Make sure your air flow is ok. The air flow provides the signal for the computer to inject gas and you may have nothing but a dirty air filter. I still think it's the fuel pump, but until you get the pressure checked it's hard to narrow it down further.

[zechirian]

Yeah when i got the car (2months ago) they had just put it through a $1500 tune up, wheel jobber.. not sure what else for $1500 but i did check the air filter and its brand new.. its brighter than my socks hah. K I will probably have to take it in to our mechanic for this fuel pump thing. Scary thing is the fuel pump is $400+ unless i can find it elsewhere like Ebay.

[Doug Tatham]

If it is the fuel pump, I don't recommend ebay. I have bought a fuel pump there before and it was ok, but you're taking a chance. I checked sasponline.com and they had one for $171 without the sending unit. I'm not recommending them in particular, just giving you an idea.