Dead in the water, any ideas?
 

About a week ago my wife was out shopping and called saying "the car won't go". I had it towed home and have not been able to look into it yet so I wanted to pass it by the forum before I dive in this weekend.

It will start and idles rough. When you hit the gas, there is zero acceleration. It sits at the 1000rpm idle, but runs more smoothly with the pedal down. There are no codes popping up so I really don't have much to go on.

Would a bad MAF cause something like this? That was the first thing I was going to check into but I'm open to any ideas you guys may have.

TIA! :cheers:

I'd definitely be thinking either the MAF, or maybe an 02 sensor... the mixture is not getting there correctly.

You should be able to just disconnect the electrical connection to the MAF, which will put the engine in a default/safe fuel/air map. If it runs better with the MAF disconnected, it's likely a bad MAF. If it doesn't change... might want to have a shop check the computer to see if any of the 02 sensors are giving bad readings or something.

otherwise, it could be a fuel system problem... or maybe an ignition problem?

Did she fill it up with gas while she was out?

My "Wife" ;) filled the car up an topped off (before I knew ... errr I mean she knew better) and had a similar experience.

I wonder if the fuel filter could be cloged up? Fuel system is my first thought it would make sense that it didnt throw a code too I imagine.

John, sorry to hear you and your Boxster are still out of commission. You have been having a long streak of bad luck. :(

Hi,

All good suggestions so far, but the list of possibilities is much longer. Start with the basics, Fuel, Air, Spark (you have durametric right?) get a real-time data stream and see where it leads you. Good Luck... !

Happy Motoring!... Jim'99

Thanks for the suggestions guys.

I had a few minutes so I ran outside and unplugged the MAF and it runs just fine. I put in the new MAF I had purchased awhile ago when my P1502 problem first started and it went back to running the same way it did with the old MAF. The nice thing is with the MAF unplugged my P1502 code has gone away and it runs like a champ so I may be getting closer to finally fixing that problem.

I'm wondering if I need to have the computer flashed. When I ordered the new MAF, I got the exact same one that was in it from the factory rather than get the updated one and have to get the computer flashed. Maybe I should just go ahead and order the updated one and take the Box in for a reload.

I'm going to drive it to work tomorrow with my AutoTap plugged in and recording all of the sensors as I drive so I can see what's happening, but I don't expect much from that since the MAF is unplugged. I'd use the Durametric, but it doesn't give me as many real time stats as the Autotap, though I'm guessing in default mapping mode the computer won't be monitoring most of the sensors.

Any other suggestions?

Oh well, so much for that. This morning I went out to drive her into work and record everything and it's back to barely running again with the MAF disconnected so it's back to the drawing board.

Hi,

I wouldn't expect it to run well with the MAF disconnected. I never advocated running the car witout the MAF, that's just a diagnostic. The Default MAP makes the car run like crap.

Have you disconnected the Battery yet so the DME resets itself? That's where I'd start. Hope this helps...

Happy Motoring!... Jim'99