can anyone please help

can anyone please help me? i need all the help i can get

I have a 1997 jetta 5 speed. the other day my boy friend put in my head unit everything was working fine till that,its been stalling at every red light or stop sign. could this have anything to do with the radio or the battery? and another qustion where is the reset button some people are saying push that. could that spark plugs have anything to do with it.

With what you have included, it doesn't seem that the head unit would have any effect that drastic. Does it stall when you pull up to the light, or when you pull away? It's probably either the timing is off, or the idle is set too low. But it's very hard to say. What engine do you have? How many miles? Any parts you recently changed? If you start the car and let it run in the driveway without moving it, does it still stall? Does the engine come up to normal temp? Did you put bigger speakers in as well as the head unit, maybe some subs?

The list of things that could be wrong is very long... from an alternator that's going bad, idle too low, timing way off, bad plugs/wires, coil, air intake plugged, dirty fuel filter, bad o2 sensors, bad cat... Describe what the car does when it stalls, when it happens, and things that you can do to keep it from stalling (give it gas...). Does the car start right up again after it stalls? Check engine light on?

it stalls as soon as you pull up to a light.how do you know if your idle is set to low.its a 2.0 159,000.there is no new stuff on it.usually he can turn it on and it stays on but as soon as he pulls away it stalls.there is subs in it.we put this stuff in the gas tank yesterday to clean it.sometimes when were about to stop he gives it alittle bit a gas and it doesnt stall. but it starts right up after.there is no check engine light on.

The idle for that car should be set near 800 rpm's at a standing idle at normal temp. It sounds like a filter problem to me, but I'm not confident enough to suggest you go change them yet. Be patient, and someone will comment who knows a little more about your model jetta.

could it possibly be the cadilac converter

It's possible, but unless it's really awful it shouldn't stall the car every single time. As well as the car would idle very funny even just sitting in the driveway warming up. Why, did the cat take a smack from a speed bump or something?

Have you replaced the fuel filter?

ALso try cleaning the throttle body with some throttle body cleaner.