S Engine (Sometimes) Dies During Hard Acceleration Around 5000 Rpm

[cr8on]

I have been having an intermittent issue with my '02 Boxster S, where it will cut off the engine during hard acceleration, typically above 4000 rpms. It kind of feels like I have hit the rev limiter due to the abrupt loss of drive, but hitting the clutch and grabbing another gear does no good. The engine has died, and so far, the only solution I've found is to turn the ignition off and restart the car (while you are coasting in traffic). Not cool! It does not appear to be the electrical system cutting off, just the engine, as near as I can tell. I'm usually in a bit of a panic to get it restarted and moving, again. Anybody else seen this, or have any ideas?

[Loren]

Check for fault codes and pending faults. I suspect you have an MAF problem.

[cr8on]

Check for fault codes and pending faults. I suspect you have an MAF problem.

Had a CEL due to MAF, a few months back, which conveniently came right as I was ready to add a CAI. Took care of that then (I think).

I experienced the problem again today, at a place where I could just pull off the raod and investigate. Turns out the engine had not died, at all, but I virtually lost throttle response. The engine was running idle, and all electronics still running, but when I hit the throttle the engine only revs up 100-200 rpms. Restarting the car clears it.

[Loren]

Check your fault codes - there is a fault code for throttle position sensor.

[cr8on]

Check your fault codes - there is a fault code for throttle position sensor.

Had the dealer checked it out, today, and they reported a fault code P1508 Torque Monitoring Comparison. Their solution was to replace the DME "per Porsche a TSB"... I didn't.

[golinu]

Hi,

I have exactly the same problem than you with my Boxster S from 2002. Sometimes,in high acceleration, the power move down dramatically :-(

I need to stop and start the engine to clear the problem.

It's now the 3rd time I have this. I have the same error code P1501 (and P1505 / P1508).

Did you finally found the problem ???

Does your Boxster fully original ? I mean did you change something like the exhaust ?

Did you had issues with the Lambda ?

Thanks in advance to share with me your experience !

Cheers.

Christophe from Toulouse (France)

[Loren]

Hi,

I have exactly the same problem than you with my Boxster S from 2002. Sometimes,in high acceleration, the power move down dramatically :-(

I need to stop and start the engine to clear the problem.

It's now the 3rd time I have this. I have the same error code P1501 (and P1505 / P1508).

Did you finally found the problem ???

Does your Boxster fully original ? I mean did you change something like the exhaust ?

Did you had issues with the Lambda ?

Thanks in advance to share with me your experience !

Cheers.

Christophe from Toulouse (France)

I don' see how these could be related unless your DME and/or throttle jacking sensor harnesses are damaged..

P1501 Throttle Jacking Unit, Output Stage – Signal Implausible

P1505 Throttle Jacking Unit, Control Range – Open Circuit

P1505 Throttle Jacking Unit, Control Range – Below Limit

P1505 Throttle Jacking Unit, Control Range – Above Limit

P1508 Torque Comparison Function Monitor – Signal Implausible

[golinu]

I don' see how these could be related unless your DME and/or throttle jacking sensor harnesses are damaged..

P1501 Throttle Jacking Unit, Output Stage – Signal Implausible

P1505 Throttle Jacking Unit, Control Range – Open Circuit

P1505 Throttle Jacking Unit, Control Range – Below Limit

P1505 Throttle Jacking Unit, Control Range – Above Limit

P1508 Torque Comparison Function Monitor – Signal Implausible

Would it be possible that my DME and/or throttle jacking sensor harnesses are damaged unless it happears randomly ?? I have made arround 5.000 kms between the first time I had the problem and the last time.

[Loren]

If it is random then it could be a bad connection or bad throttle jacking sensor.

[golinu]

Thank you Loren for your fast help.

I will check my connections and will clear them ;)

This is an easy first step B)

Chears

[cr8on]

Sorry to hear that you are experiencing the same problem! I don't have any further info, than I previoulsy reported. The local dealer told me they found fault code P1508 (Torque Monitoring Comparison) and their only solution was to replace the DME.

I have slowed down... how ofter I drive it, and how fast I accelerate in first gear. I've never had it happen in any other gear.

Creighton

SkankTees