Not based on my experience...

My 2002s (88K miles) would not start on Monday morning so I had it towed to my indie and they report that the plugs were fouled; once replaced the car started and ran fine.

I suspected that this might be the cause, here is what happened:

I am in NJ so it was cold and snowing last Friday. I drove it home after work and left it in the driveway overnight. On Saturday I started it up and put it in the garage, total running time 15 seconds.

Monday I tried to start it and it almost caught but did not start; further attempts were futile.

Is this a common occurrence?

I have found, not just with the Boxster, but other cars too, that a short startup like yours, specially in cold weather will result in the car being harder to start than usual on the next startup. Eventually, they've always started though.

Do you know if those were the original spark plugs? If so, they were overdue.

Do you do a lot of short drives (just a few miles}. That will foul the plugs - even more so in cold weather because you're always running on a rich mixture.

quick starts and stops int he cold cause the car to flood. When it floods, it needs to be cranked like crazy. More than you would ever imagine, foot to the floor, to start. Not only this, but lots of short trips int he cold means the motor is always running rich - bad in many ways; fouled plugs, contaminated (gas dilution) oil, wash down of oil on the rings/walls.

In general, get it started and 20 minutes at temp, running sotchiometric, cleans things right up.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Foot to the floor to open the throttle and lean the mixture? (Without pumping, right?) Would this work at all with an e-throttle?

foot to the floor to get air through the cylinders and rid the flooded fuel.

e-throttle. Hmm, probably. If power is fl;owing, and circuits are active, the pedal signal should be passed to the stepper motor, yes.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

If the engine cranked just fine and didn't fire it could be the first signs of a failing fuel pump.

Another explanation is the battery was down and being in the shop for the plug change warmed up the battery and resurrected it.

And of course there are other less common explanations.

If the fuel pump or battery is the explanation, things will be ok.

For a while.

I do agree with Guenter if the plugs had 82K miles on them they were due to be changed.

As an aside, I've never experienced any plug fouling in any of my cars ever. The only time I have experienced fouled plugs is with a motorcycle engine when upon removal the plug was very wet with fuel or there was some material bridging the distance where the spark would otherwise jump across. In this latter case the plug fouled not from being doused with fuel but from lousy combustion putting deposits on the plug tip.

But what I have encountered a couple of times is after the engine being started in cool weather and the car moved just a hundred feet that upon the next engine start while the engine fired up it misfired from the cold/dampness. The cold/dampness was not the worst the car has seen either. Sort of weird in that way.

Anyhow, this misfire has only occurred 2 times in all the years/miles I have owned/driven the car. (In spite of the misfires I have not yet had the coils replaced. The techs report when they do a plug change the coils look ok, still.)

If it is the fuel pump. or the battery (or something else), you'll know it soon enough. The no start symptom will return.

Wouldn't a failing pump cause the plugs to show a lean condition, if anything?

and unless the pump (or pressure regulator) fails in such a way to deliver less fuel that the engine runs lean.... but then you have the DME which will adjust the fueling -- extend the injector active times -- to compensate.

You would also likely see the CEL on (flashing on too) from "rich" misfires which put the converters are risk of damage from overheating from the raw gas being fed them.

In modern cars about the only time you'll see a 'fouled' plug is if an injector is leaking, or if the engine is being too richly fueled due to a temp sensor failure that reports the temp less than it really is.

Otherwise these modern fuel injected engines are very precisely fueled.

That is the function of the DME and is done so in order to protect and satisfy the very stringent exhaust gas composition required by the converters so they can do their jobs right and the emissions are kept at acceptable levels.

Prior to modern engine control systems 'fouling' generally arose from the lousy state of tune car engines had or a fault with the carb float. Even then the plugs didn't foul. For instance my early Datsun 510 was running rich traced to a fuel line coming apart and pieces jamming the float so excess fuel was in the float bowl. The engine did not misfire, or act like it had fouled plugs. It emitted visible dark exhaust smog and had lousy fuel mileage. This was back during the 1st gas crisis and it was my paying attention to the fuel mileage that really clued me in something was amiss. Another insidious failure mode was the float would develop a crack in its outer layer which would allow fuel to soak into the float and of course it would get heavier and allow the fuel level in the float bowl to rise with the result the engine would be running rich.

More often, many an owner fouled plugs by pumping the gas pedal too much and causing the accelerator pump to flood the engine and foul the plugs. This is where holding down the gas pedal to open the throttle wide and cranking the engine to let the plugs dry out came from.

People do not realize how serious this precise fueling is. There is the initial emissions compliance the car must have, not to mention being able to come somewhere near the EPA says the fuel economy should be for a particular vehicle. There is the new car warranty time during which the engine must run right. Then for some emissions related components there is the federal emissions hardware warranty laws which require the factory to replace any failing components at its expense. The big ones are the converters.

Then the EPA constantly -- through contractors -- brings in every day passenger vehicles for emissions compliance testing. If the EPA started to notice a too large a number of a particular make/model of car failing to remain there would likely be serious repercussions to the automaker responsible.

Speaking of floats, when a friend and I tag-teamed cross country in a couple of Volvos, his B18 developed a flooding problem high in the Appalachians. We determined that the fuel bowls were flooding, and "fixed" the problem by taking off the covers and bending the float hinges one way or the other.

The next issue was the generator light coming on in Phoenix (113º) and not seeing or hearing anything obviously wrong. One morning the car wouldn't crank and we asked a guy with a Jag to give us a jump, but he wouldn't as he was afraid his car would explode. We were understanding: Lucas electrics. Someone else gave us a jump. We had done most all our driving in daylight, but one night we were driving on the California coast when the car rapidly died. Apparently the headlights being on drained the system past what it could generate. Some chick in a beat up truck with no gas gauge picked us up and drove us to her boyfriend's beach house where we called a friend of ours in Goleta. The next day we fixed the problem by unsticking a relay/solenoid(?) inside the voltage regulator.

The car had no other issues for thousands of miles, but it was such a weakling, and its automatic transmission left in Drive would hunt back and forth when we drove up Mount Evans: Gain speed; upshift; lose speed; downshift; gain speed...

Thanks for the responses.

My typical oneway commute is 14 miles, 5 times per week. 9 miles of this is at highway speeds.

I have also experienced the hardstarting/misfire that Marc mentions when restarting an engine that was not run for long

I was on the verge of the 90K service so the plugs were due and the indie is preforming the rest of the 90K.

I wonder if you had a/some bad leaking O rings on the spark plug plastic
shields? I had one that was leaking badly onto one of my O2 sensors and
gave me a CEL.

Did your mech give you back the old spark plugs so you could inspect
them? Did he replace the plastic spark plug shields and O rings? Just a
guess.

Back in business, the codes were checked and none were found. Only downside was that I missed the one 60 degree day all winter.