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Intermittent failure to turnover - '97 Boxster

I just replaced the MAS on my '97 Boxster @ 55,000 miles. The
car runs fine, idles and accelerates properly. No "check engine" light
appears. No other adjustments were made. Battery was disconnected.

I live in Greenville, SC where the July temp is 88-90. Now,
intermittently, the Boxster will fail to turnover after a short drive.

So far (6 outings), it will start within 10' of the first try after initial trip
and and run fine. Battery is new; starter is, likely, original, but shows
no signs of failing.
I have had trouble in the past pumping a FULL tank of gas into the car.
Today, I made sure the tank was completely full ... took 5 tries after
initial auto shut-off.
> Any relationship to new MAS?
> Any other sensors failing?
>?
THX! Doug Stowell

Quote:

Originally Posted by DWSTOWELL (Post 638336)

So just so we are on the same page.
Are you saying the engine fails to crank (turn over) after it is warm.
as in nothing happens .
Or are you saying it cranks but does not start???

No the issue is not related to the "MAF" sensor.

The only way to know if you have other sensor issues is to scan the DME/ECU for pending codes.
And look at all the sensor signals.

Sounds like the Crankshaft Position Sensor (CPS) is failing. They tend to fail intermittently when warm before completely failing. It can be accessed from the passenger side rear wheel well, I think the sensor from Bosch is like $65.

Also, the fuel tank triggering the auto shutoff on gas pumps is known issue. I don't recall the fix, mine was repaired by the dealer, something to do with the fuel line slipping out of place.

If I understand you correctly, Your car starts/runs fine when cold. Then fails to start (cranks/no start) later once the engine is warm. Is this correct?

I know some have had similar experiences with fuel pump relay failing.

As far as the crank position sensor mentioned above, see if your tach moves when you are cranking during the no start condition. Tach moves, CPS most likely good. Tach stays at 0, CPS bad.

"Failure to turn over" as in no response from the starter? How about the clutch interlock switch? Not related to having just run, but often an intermittent failure.
https://www.pelicanparts.com/techarticles/Boxster_Tech/93-ELEC-Pedal_Switches/93-ELEC-Pedal_Switches.htm