StatmanDesigns

My 2000 Boxster S needs a new MAF sensor. Apparently my car has the "old style" MAF. Looking on P. Parts website there are quite a few different ones to consider. First question is what is the "old style" part number? Is the "newer style" compatible as well? And is there significant difference in brands, as there is significant difference in prices. Thanks for the insights...

mikefocke

More than you want to know about the MAF including part numbers and tools needed are here. But also know that many problems that seem MAF related are not and are caused by something else. What codes are you getting that cause someone to suspect the MAF?

StatmanDesigns

Thanks for that. Took my car to the local Porsche dealer to have the CEL read. They did not report the codes to me, but diagnosed the car as getting inconsistent readings from the MAF sensor. They said it needs to be replaced. I will try the cleaning method first. Thanks for the link...

StatmanDesigns

Mike, I finally had some time and weather to drive the car after the CEL was cleared. After about 40 miles it threw another CEL, I read the codes with a generic reader as P1128 and P1130...any insight is always appreciated

Brian in Tucson

Double post

Brian in Tucson

A note on Amazon "Used" parts, they save you about $100 and have the easy money back Amazon guarantee. For mine, the cost of "New" was $161, "used" was $62. The only difference I can see is that the "used" MAF sensor box is a little scuffed. Easy money!

Brian in Tucson

Mike Focke's write up is excellent!

Macster

P1128 Oxygen Sensing Adaptation, Idle Range, Bank 1 – Above Limit
P1130 Oxygen Sensing Adaptation, Idle Range, Bank 2 – Above Limit

Possible fault causes:
– Incorrect signal from MAF sensor
– Intake air system leaking
– Fuel pressure too low
– Volume supply of fuel pump too low
– Fuel injectors fouled
– Exhaust system leaking

My experience over the years is the MAF is not the cause of these errors. That doesn't mean it can't be as the list of possible causes clearly indicates.

Most often, in fact every time, the MAF was not at fault.

One time the problem was an AOS. When this fails, early on, it is just an air leak.

Another time I replaced the MAF only to discover a few days later -- and after the P1128 error code returned -- the problem was a leaking oil filler tube cap. With the engine idling see if you can move the cap and if the engine reacts or you hear a vacuum leak.

Another time I managed to leave some leaves in the air box when I changed the air filter. The leaves fluttering at the plastic mesh that resides just ahead of the MAF caused the MAF to produce inconsistent data.

While the leaves were a problem and dealt with the P1128 error persisted. After several attempts to get to the bottom of this with no luck and facing not only a probably big repair bill to finance an expedition by a Porsche tech to get to the bottom of this error and then a new clutch/flywheel on top of that I decided that after 16 years and 317K miles to dispose of the car.

StatmanDesigns

Hoping it does not come to this...rofl

Thanks Macster, always a pleasure. Side note, I just had the Dinan-elite engine module installed on my 2017 MINI JCW, picking it up today

Macster

Didn't mean to imply you're facing a real car killer of a CEL problem.

I think you'll get your car sorted out though it may take some good diagnostics. (Shortly after I got rid of my Boxster I gathered up all the reference books and gave those to someone who owned a Boxster so I have no Boxster specific OBD2 references any more. Well, except for the thick 3-ring binder of OBD2 stuff that came with the factory manual I bought. Tell you what: Private email me with your mailing address -- be sure to reference what this is in regards to -- and I'll send you the 60lbs of Boxster factory manuals for free. I'll even pay the shipping to make it easy/peasy. I have no use for them anymore and they are just taking up space in my already cramped apartment.)

In 317K miles I only had to replace a MAF once, and it was a replacement MAF I bought when I misdiagnosed the oil tube filler cap leak for a bad MAF. This replacement MAF eventually -- after around 100K miles did go bad -- I forget the symptoms/error codes now unfortunately -- and I replaced it with the old MAF, which I had saved. The old MAF worked just fine and I continued to use it until very recently (this last year) when the engine was triggering a CEL with I don't recall the error code off hand but it was once in a while a too rich a mixture. Suspecting the MAF I replaced it.

The new MAF made a difference in how the engine ran, it ran better, but it proved to not be the solution. Despite the fact the new MAF wasn't the answer that the engine ran better with a new MAF installed indicated to me there might be some benefit to replacing a MAF *before* it gets to the point it does generate a CEL. But when? Another can of worms.

(Hah! Just occurred to me that maybe you don't want to listen to me about MAF's. I'm 1 for 3 properly diagnosing MAF problems.)

What proved to be at least part of the problem is the leaves I mentioned previously.

But unfortunately not all the problems were due to the leaves, as I also previously mentioned.

Dinan Elite? I've heard of Dinan in regard to BMWs but not Mini's. I'll have to do a search and see what that module does.

Got over 4K miles on my JCW. It is a great car, a pretty sporty car what with 228hp and 236 lb ft of torque compared to my Boxster with 215hp and 192 lb ft of torque and both cars weigh in at close to the same weight with I recall the JCW coming in at 2845lbs and while I don't recall the Boxster's weight it is close to that number as to be essentially the same. Anyhow a great car, except those run flat tires kind of suck but not enough to cause me to dispose of them before their time, and I'd drive the JCW more but 2 months after I bought the new Dodge Challenger R/T Scat Pack, the white car with the black wheels ( I posted pic at various sites ), I traded the R/T Scat Pack in for a new 2018 Dodge Challenger Hellcat in Octane Red. I love driving that crazy insane Hellcat. (Over 2700 miles on it since Feb. 17.) While I refer to the JCW as the little (rebel) green beast that Hellcat is the real beast.

Just occurred to me I can post a pic here.. Not a Boxster but what the heck...

Brian in Tucson

Confused about the thread, I deleted this entry.

Macster

Started out about a possible Boxster MAF issue, but I took it off track a bit. My bad.

Feel free to chip in if you want.

StatmanDesigns

Brian, Macster and I both coincidentally have Mini John Cooper Works models, so the thread may have lost its way a bit. I have cleaned the old MAF and changed the air filter. Filter was dirty and there was one leaf under the filter, so maybe that was partly to blame. I have only driven about 30 miles today and no CEL and the car runs as well as it ever has, we will see after a week or so if the CEL reappears...Macster, your insights on MAFs is more than welcome, hall of fame baseball players have about a 1 for 3 record as well, so it can't be too bad...the Hellcat must be awesome!

Macster

Because you have found at least something in the air box that doesn't belong, be sure there is not any more leaf or leaf fragments in the air box.A good shop vacuum is a good way to remove any trash/dirt from the air box.

Also, be sure to check nothing is caught at or laying just in front of the mesh screen that is inside the air intake tube that runs from the air box to the TB and thence to the intake manifold.

Last but not least you probably should (carefully) remove the TB and clean it. In the case of my Boxster the tech found a small leaf fragment stuck to the butterfly valve.

"the Hellcat must be awesome!" Oh yeah.

StatmanDesigns

MAF update: The dealership wanted $1100 to fix my check engine light, CEL, issue claiming that my MAF sensor was bad and they wanted to replace it. I took the car home after buying a new air filter at the dealership. Stopped at auto zone for a $7 can of MAF sensor cleaner. Got home, took the access panels off for the top of the engine and pulled out a dirty air filter, cleaned up the inside of the airbox (one leaf in there). Took the MAF sensor out, sprayed it off and let it air dry for a couple minutes, and then reinstalled. Put the new air filter in and closed it all up. Total time investment about 45 min. Have been driving the car in this awesome Spring weather and after about 300 miles there has still been no CEL. I might be in the clear, and the car is running the best I can remember. Love the helpfulness of this forum...Thanks everyone.