What do you think is going on with my Box? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

CJ_Boxster · 09-25-2006, 02:05 PM

This morning before work i made it just barely to the gas station, i think 1 more minute i would have stalled with no gas. After refueling, i noticed alittle delay in responce when leaving in 1st gear...almost like a missfire prior to the engine rpms going past 1000.

When in the garage at work was test reving the engine to 3000 rpms and noticed the little thud or missfire as soon as i press the accelerator, Like this: Pressed accelerator, thud then rpms go up. This isnt TOOOO noticable but i can tell since im anal about my cars performance. I also noticed alittle more difficulty shifting smoothly since the engine rpms didnt want to match up so easily after the issue started to happen while leaving the gas station.

1997 boxster 2.5 5 speed manual

09-25-2006, 02:25 PM

I don't know for sure.

But, running low on fuel is not good. You may have sucked some sediment into your fuel system or clogged your fuel filter. Also, I think our cars have the fuel pump in the tank, which helps to keep the pump cooled. When you run the fuel level very-very low, there is no fuel available to cool the pump, which can shorten the life of the pump.

CJ_Boxster · 09-25-2006, 04:30 PM

Thanks, im thinking its something like that, Where is the fuel filter located?

09-25-2006, 06:00 PM

CJ, I am not sure, but I have seen pictures of the fuel filter location either here or on RennTech. Do a search, and I am sure you'll find it. Sorry I can't help any more than this.

CJ_Boxster · 09-26-2006, 11:35 AM

Oh did a search, its right behind and between the seats. I also noticed yesterday, Say for example if i pu the car in 4th gear, about 1500 RPM's and press the accelerator, the car will sorta sputter once or twice until it reaches 2k rpm's. I think Im experiencing alittle fuel starvation, I will be first replacing my fuel filter since its the cheapest thing in the list of fuel related item that could be bad. I really dont think my fuel pump is gone bad.

I think as a result of me driving with nearly no gas and on the vurge of stalling in less than 10 seconds...I may have sucked up alot of sedement from the bottom of the tank and since im sure my filter has never been changed ever, Im sure it already had some junk in it, and yesterdays low fuel debockle just put the icing on the cake and now i can actually feel the starvation.

But thats all wishful thinking....cross my fingers im right.

Gary Gaukler · 09-26-2006, 08:18 PM

Quote:

Originally Posted by CJ_Boxster

Oh did a search, its right behind and between the seats. I also noticed yesterday, Say for example if i pu the car in 4th gear, about 1500 RPM's and press the accelerator, the car will sorta sputter once or twice until it reaches 2k rpm's.

You're lugging the engine if you accelerate from 1500rpm in 4th gear; don't do that.

CJ_Boxster · 09-26-2006, 08:38 PM

Oh i know under normal circumstances i wouldnt do that but i needed to do that so i can better understand the issue im having.

CJ_Boxster · 09-30-2006, 01:28 PM

Ok all this week, that fuel i bought has lasted me til today, i Put some more gas from a cheveron in Palos Verdes and after a quick drive on the freeway to Downtown Los Angeles Porsche to get the new fuel filter the car no longer shows symtoms and the power is back!!! The service tech says theres a good chance i got some bad gas and that it happens sometimes.

Something could have happened at the station, my pump i used has another pump on the other side of it for other customers and it was ripped off and a tech was there replacing it and told me that this happens all the time at this station so maybe this may have something to do with my car acting up.

Ill replace my filter anyway since it has 99k miles on it.

MNBoxster · 09-30-2006, 02:25 PM

Quote:

Originally Posted by bmussatti

I don't know for sure.

But, running low on fuel is not good. You may have sucked some sediment into your fuel system or clogged your fuel filter. Also, I think our cars have the fuel pump in the tank, which helps to keep the pump cooled. When you run the fuel level very-very low, there is no fuel available to cool the pump, which can shorten the life of the pump.

Hi,

Sucking up any sediment isn't likely to cause the problem because the fuel filter will catch it. The Fuel Pump also has a screen on it, so that's not likely the issue (it's take practically a handful of sand to clog both of these to the point of fuel starvation).

More likely Bad Gas. It's wisest to buy your fuel from the busiest name-brand station in your neighborhood. Because they're busy, they are constantly emptying the tank and refilling it which allows much less sediment and moisture to accumulate.

Also, the no-name, discount, stations have been known for some unscrupulous practices. The last time Fuel prices peaked, I actually saw an attendant at a no-name station putting a garden hose down the tank spout. 50 gal. of water would allow him to steal $150 (@$3/gal.) from the station unoticed. In a 20k gal. underground tank, the dilution would be so slight that most cars' ECU would compensate for it and no one would notice. Hope this helps...

Happy Motoring!... Jim'99

Brucelee · 09-30-2006, 03:26 PM

I use Chevron exclusively and have had great success with it.

The gas here in CA is generally crap so it is necessary to find a good gas and stick with it.

CJ_Boxster · 10-02-2006, 10:19 AM

My symtoms are still present, i believe 100% that my fuel pump is the culprit. I guess i didnt feel the symtoms right away cause i was driving differently so that i wouldnt feel the miss in low RPMs, but not that i leave a stop at 1500 rpms i can feel the miss. I think when i ran dry i damaged the fuel pump...oh well the fuel filter needed to be replaced, it was pretty touch to blow air through it and the idle and start up idle is alot better than it was before the filter change.

CJ_Boxster · 10-02-2006, 10:47 AM

Any body know of a salvage yard that might have a fuel pump on hand?

I cant afford at this time to pay for a new one from the dealer or suncoast.

insite · 10-02-2006, 11:32 AM

german auto dismantlers

http://www.germanautodismantlers.com/

CJ_Boxster · 10-02-2006, 12:40 PM

Insite, thanks! i just ordered one from them for 85 bucks, 90 day warranty!

I cant wait to feel the missing performance again that my boxster is lacking at this moment.

insite · 10-02-2006, 02:20 PM

no sweat! those guys are awesome. take care.

silversharkgt · 10-04-2006, 04:13 PM

You better check the spark plugs, man. Sounds like it's about time for new ones anyway if you have 100k miles. Do you perform regular check ups and maintenance?

MNBoxster · 10-04-2006, 07:47 PM

Quote:

Originally Posted by silversharkgt

You better check the spark plugs, man. Sounds like it's about time for new ones anyway if you have 100k miles. Do you perform regular check ups and maintenance?

Hi,

I agree. Seems a somewhat as needed, haphazard approach. I'm not sold that a fuel pump is the lister's problem, though it seems he does...

Happy Motoring!... Jim'99

CJ_Boxster · 10-10-2006, 01:16 PM

replaced the plugs about amonth ago before this issue arose...I think it would be too much of a coincedence to be something non-fuel system related given the circumstances.

xclusivecar · 10-10-2006, 02:48 PM

I had the stumbling acceleration/misfire problem and it was the MAF. I know your the guy who is in love with your K & N, but maybe the MAF has crapped out on you.