Another hard starting question
 

Before you all jump on me and tell me to search the forum, I did!
For the past several weeks it is hit and miss if the car will fire right up. If it doesn't, I have to crank it for about 10 seconds before it starts, then need to push the gas pedal a few times before it settles in. The hard start randomly occurs whether it is a cold or hot start. Last night after a few hard starts, I was at a stop light, idling when the car suddenly had a slight increase in RPM, then died. Fired right up after each occurrence.
I do get frequent P410, P1410 , P1420 CEL codes and yesterday I got my first P420 code.
Previous posts regarding the CEL codes, I was told the P410 was no big deal and I would just see a decrease in fuel efficiency. Not sure if these codes are related to the hard start issue. Please advise. BTW, I do have a new fuel filter standing by to install.

Definitely change the filter. I'd also check to see if you're getting consistent fuel pressure on the rail on the engine.

Does the tach dance while cranking? If so, CPS is fine. I'd look fuel related first.

https://www.porscheclubgb.com/PCGB/media/R31%20assets/Docs/tec_dtc_pcodes.pdf?ext=.pdf

P0410 and P1411 are SAI issues. Those don't typically affect start up.

P1420 isn't listed in the Bentley Boxster repair manual.

P0420 means the catalytic converter isn't working properly. This can be the cat itself, the O2 sensor, or the wiring.

To my thinking, I don't think that any of these would cause a hard start problem. The SAI only affects emissions at cold start and the cat/O2 sensors aren't part of the system until the ECU goes into closed loop operation after startup.

With that being said, the obvious place to begin troubleshooting is to correct all of the obvious faults/codes and then go from there...

I chased a hard hot start for a bit and it ended up being the MAF. Has it been changed or serviced recently? Might be time for a new one.

OEM MAF installed about a year ago. Took it out last week and ran some MAF cleaner on it. What concerns me is the slight increase in RPM while idling, then stalling. Fortunately, it fires right up after stall.

Remove & clean throttle body?

The increase in rpm sounds a lot like a vacuum leak. Maybe start checking hoses or do a smoke test.

Not sure about the source, but for P1420 Porsche P1420 Secondary Air Valve Control Circuit Electrical.

As for chasing a vacuum leak you can use this article for some assistance: Porsche Boxster Vacuum Leak Troubleshooting - 986 / 987 (1997-08) - Pelican Parts Technical Article. Good luck and let us know what you find out.

Been there, done that. No change.

You might be on to something. Last time I had the lid off, I thought I could hear some sucking air from the drivers side. Will poke around to see what I can find. Is there a "homemade" tool to do a smoke test?

Yup!!

I made one for an old child's nebulizer and a 1 gallon oil jug.

Jug for smoke machine, I love me some BrakeKleen!!

http://i70.photobucket.com/albums/i1...psesbdalm8.jpg

Drill hole in top and insert some 5/16" fuel hose to accept the smoke maker

http://i70.photobucket.com/albums/i1...ps2aipjmuy.jpg

Drill hole in bottom to accept the input from the nebulizer or other air supply. Low pressure medium flow.

http://i70.photobucket.com/albums/i1...psimi3fwvu.jpg

Head over to the local corner store and buy a few of the cheapest plastic tipped cigars they have. I got mine at 0.15 cents each. Push unlit cigar into inside of cap hose so that it will smoke when air is applied.

http://i70.photobucket.com/albums/i1...pslchqkcce.jpg

Airline in

http://i70.photobucket.com/albums/i1...psy6psheza.jpg

light cigar

http://i70.photobucket.com/albums/i1...ps9orb6y38.jpg

Insert into jug with air on to keep it going.

http://i70.photobucket.com/albums/i1...psboh7a4yj.jpg

Get lots of smoke!

http://i70.photobucket.com/albums/i1...ps0f8syte7.jpg

Attach to intake, plug up exhaust and intake system to keep the smoke in. Now look for where the smoke is getting out.

Thanks, looks like I have a DIY project when I get home.

Changed out fuel filter this weekend hoping that would end the stalling issue. It didn't. After a 30 minute drive, I shut down the car, went into a store for 15 minutes. Took several tries to get it started, then once it started, it stalled a number of times, once while driving. The rest of the time it stalled while at a stop light. RPMs were at 1000. Stopped again when I got to my next destination and it fired right up and RPMs were at about 800 and no stalling issues. Regarding the hard start issue part, my tack barely "quivered" while cranking. What should it look like while cranking?

HELP!!! I am afraid to drive it out of fear of getting stranded.

Do you have access to a Durmertic setup???

Unfortunately, no.

I use this Smoke Machine from KustomSmoke at home. Works well with a few upgrades.
https://www.youtube.com/watch?v=q9C0bJZYgMc
See Post #6 here:http://rennlist.com/forums/boxster-and-boxster-s-986-forum/531407-looking-for-the-last-word-on-p1124-and-p1126-fault-codes.html