Today my 986 died on the Bay Bridge - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Lucky · 05-27-2010, 06:34 PM

Quote:

Originally Posted by Oaktown 986

when the MAF was disconnected; it ran rich (it smelled of gas and couldn't easily maintain idle). Does that help?

When you say it won't rev beyond 3k, is this while driving or just sitting in your driveway in neutral?

Oaktown 986 · 05-27-2010, 06:40 PM

Quote:

Originally Posted by Lucky

When you say it won't rev beyond 3k, is this while driving or just sitting in your driveway in neutral?

driveway in neutral; i drove it a couple days ago, and it wasn't pleasant. now in neutral it's barely getting beyond 1500. ugh.

Lucky · 05-27-2010, 07:08 PM

Quote:

Originally Posted by Oaktown 986

driveway in neutral; i drove it a couple days ago, and it wasn't pleasant. now in neutral it's barely getting beyond 1500. ugh.

Since you've tried the obvious fixes, I really think you need to look at fuel delivery. You should be able to easily test pressure off one of the fuel rails. Most auto parts stores sell the proper pressure gauge. Just be careful since you are dealing with gasoline... don't want you starting a fire! Be prepared for some spillage when you remove the cap from the test port.

Oaktown 986 · 05-28-2010, 07:30 AM

Quote:

Originally Posted by Lucky

Since you've tried the obvious fixes, I really think you need to look at fuel delivery. You should be able to easily test pressure off one of the fuel rails. Most auto parts stores sell the proper pressure gauge. Just be careful since you are dealing with gasoline... don't want you starting a fire! Be prepared for some spillage when you remove the cap from the test port.

Do you think it's worthwhile to pop for a new MAF while I'm picking up a fuel pressure gauge? I've got 93k give or take, and it's a wear item. Also, where is the fuel rail? I've plugged fuel pressure gauges into Schrader valves before on SB Chevy motors, but not on a Porsche....

Jon

Topless · 05-28-2010, 07:50 AM

OK, signal implausible codes mean you have an open circuit in all the sensors listed. Could be a damaged wire harness, failed sensors or failed DME. These codes definitely indicate a car that runs like poo.

Advice: Stop driving/running the car and isolate and test every listed sensor. Maybe a rodent got in there and chewed things up or a harness got too close to a shiny new set of headers and melted. If you don't know how to do this process, find a good local indy who does. Continuing to run the car might just kill it.

Oaktown 986 · 05-28-2010, 07:57 AM

Quote:

Originally Posted by Topless

OK, signal implausible codes mean you have an open circuit in all the sensors listed. Could be a damaged wire harness, failed sensors or failed DME. These codes definitely indicate a car that runs like poo.

Advice: Stop driving/running the car and isolate and test every listed sensor. Maybe a rodent got in there and chewed things up or a harness got too close to a shiny new set of headers and melted. If you don't know how to do this process, find a good local indy who does. Continuing to run the car might just kill it.

Ok, sounds like the time is right to take it in. I haven't been driving it, just starting it for a minute in the driveway after replacing the O2 sensors, and after swapping in/cleaning the MAF. I'll keep everyone posted. I'll save the MAF replacement for another date. It's easy enough to replace, and I'm sure it'll come due soon.

Edit: I spoke with the local Porsche indy nearby (http://abauer.com/), and he agreed it's probably damaged wiring, MAF, or added the possibility that it's a fuel pump. I get off work at 3 PM daily (east coast hours, baby) so he agreed to take me into the shop and diagnose it while I'm present. I told him what i've done thus far (fuel filter, precat O2's, cleaned the MAF, disco'd the MAF, new spark plugs, tubes, o rings, new air filter) and he tried to, over the phone, narrow it down, but we agreed it's just time to bring it in.

I'll update y'all tonight with his findings, then we'll see what's going to be the solution.

J

Tranlm · 05-28-2010, 09:54 AM

Before you do! I've become really interested in your problem and did a google search online for possible issues (looked up "car won't go above 3000 rpm"). Here are some possible problems: Bad coil pack, bad gas, killed cylinder, bent valves, miswired ecu, error with MAF sensor.

For some reason, I really think the MAF is the culprit. One guy was able to fix it just by deleting the error code for the MAF (http://my.is/forums/f88/car-wont-go-over-3-000-rpms-fixed-185321/). The code wouldn't reset on its own via disconnecting the battery.

With that in mind, please try and ask the mechanic to use his diagonstic testing reader. Maybe the code will pop up. If it does, then he can delete it and hopefully it'll solve the problem.

tran

Quote:

Originally Posted by Oaktown 986

Ok, sounds like the time is right to take it in. I haven't been driving it, just starting it for a minute in the driveway after replacing the O2 sensors, and after swapping in/cleaning the MAF. I'll keep everyone posted. I'll save the MAF replacement for another date. It's easy enough to replace, and I'm sure it'll come due soon.

Edit: I spoke with the local Porsche indy nearby (http://abauer.com/), and he agreed it's probably damaged wiring, MAF, or added the possibility that it's a fuel pump. I get off work at 3 PM daily (east coast hours, baby) so he agreed to take me into the shop and diagnose it while I'm present. I told him what i've done thus far (fuel filter, precat O2's, cleaned the MAF, disco'd the MAF, new spark plugs, tubes, o rings, new air filter) and he tried to, over the phone, narrow it down, but we agreed it's just time to bring it in.

I'll update y'all tonight with his findings, then we'll see what's going to be the solution.

J