'99 Boxster Decelerates, Loses Power

[keithl]

1999 with 63,000 miles. Car started to decelerate, acted like it was having trouble getting gas, would intermittently surge forward then decelerate. I pulled over shut the car off, restarted
and the car drove fine. No check engine lights.

I replaced the fuel filter. Today, same problem. Car starts to decelerate, I give it gas
but the engine is having trouble revving. I stop and restart, the car runs better and I am able to return home, but doesn't run 100% smoothly. Again, no check engine lights.

Does a fuel pump go bad intermittently? I don't think it's bad gas. Ideas?

Oil cap is not hard to remove when car is running. Engine runs rough with oil cap off and smooths out when replaced.

Thanks.

Anyone, Anyone, Bueller....?

[keithl]

Wow, No one.

[Burg Boxster]

certainly sounds like fuel starvation could be a cause. Were you having the same issue before replacing fuel filter? If not, might you have missed something upon reassembly or wrong filter or bad one at that? The fuel sending unit/pump is located inside the gas tank but I think you need to confirm fuel filter is OK and do more diagnosis before digging in there.

So, confirm filter good and get the codes read... there might be some pending even though no warning lights. Doing so will get you pointed in a solid direction so you don't have to spend money replacing parts experimentally.

Good luck

[Lil bastard]

Oil fouled plugs due to bad O-rings on plug tubes shorting out the sparkplugs?

This is another possibility.

Pull the plugs and see if the insulators are wet from oil.

Cheers!

PS FWIW, it's helpful to state the mileage on your car when seeking advice.

[keithl]

Originally Posted by Lil bastard

Oil fouled plugs due to bad O-rings on plug tubes shorting out the sparkplugs?

This is another possibility.

Pull the plugs and see if the insulators are wet from oil.

Cheers!

PS FWIW, it's helpful to state the mileage on your car when seeking advice.

63000 Miles. Just changed the plugs at 62,000 and there wasn't any oil in there. Fuel filter was changed after the first episode. Thanks.

[ppbon]

Originally Posted by keithl

63000 Miles. Just changed the plugs at 62,000 and there wasn't any oil in there. Fuel filter was changed after the first episode. Thanks.

... in coincidences.
If you replaced the sparkplugs at 62K and now at 63K you have these issues, there has to be a connection.
One of your coils could be not connected properly (but the CEL would have indicated that).
Is your CEL working?
Did you remove/clean the MAF at that time?
Sure sounds like a MAF issue.
Happy Boxstering,
Pedro

[Mark_T]

Intermittent problems are the worst. They always disappear the moment the mechanic gets behind the wheel.

[986_inquiry]

Originally Posted by Mark_T

Intermittent problems are the worst. They always disappear the moment the mechanic gets behind the wheel.

Completely agree.

Most people curse that check engine light coming on but they have no idea how much worse it is when something happens and a light does not come on.