Hi Guys,

I have a 00 Si with an intake. I am having a problem with the engine stumbling. It feels like some sort of fuel problem possibly. What happens is when im driving, no matter whether cruising, accelerating, or even engine braking, the engine suddenly hesitates like its just run out of gas for like a quarter second, and then resumes. It happens with any amount of fuel in the tank, including a full tank. It is basically very similar to the way the car feels when gas is running out - its like the gas supply cuts in and out. I have recently replaced plugs twice, and it had no effect on the problem. I was going to do the distributor rotor and cap, since they are the original parts and the car has 75k miles, but it definitely doesnt feel like an electrical problem. Also, the problem is very intermittent - sometimes it wont happen at all, other times it does. Also, last week i started the car in the morning and it was absolutely terrible - its never happened this badly before, but what happened was i started the engine and felt a lot of vibration, like the fuel thing was cutting in and out constantly - and it felt kinda like the car was going to stall. I gave it some gas and held the revs at 3000-4000rpm and the car was vibrating cause it was cutting out so quickly. I would let go of the gas and the revs would drop well below 500rpm at idle - i even saw the needle drop to 0 and the ecu didnt cut in to 'save' the engine and kinda do that electronic rev-catch deal. It picked itself up off of the 0 mark though, but it was all over the place. Once the engine warmed up it stopped and started working properly. Since then it has not done this startup thing again. Do you guys have any idea what my problems could be? Im thinking an obvious course of action is to replace the fuel filter, but do you have any other suggestions?

Thanks alot

 

Try the electrical system before the fuel system. I would recommend replacing the cap and rotor. It "should" be done every 35k. New spark plug wire wouldn't hurt either. Otherwise, it is a fuel problem. Check for clogged fuel filter, etc, etc.

 

check the igniter in the distributor because them things seem to give this sort of problem.

 

Amen! 90% of fuel system problems are actually ignition system problems -- they just feel like fuel system problems.

I'm with Shmoo -- betcha a new cap and rotor will fix things.