Check Engine Light on - advice/help?

[Lil bastard]

Here are the explanations for the codes you have:

P1128 Oxygen Sensing Adaptation Range 2 (cylinder 1-3) - Enrichment limit
P1130 Oxygen Sensing Adaptation Range 2 (cylinder 4-6) - Enrichment limit

These are Range 2 faults which covers the engine operating state close to idle. And Type 4 faults meaning Short to B+ / Above upper limit / Rich mixture threshold

It's not likely you'd lose O2 sensors from both banks simultaneously.

The Factory Repair Manual lists possible issues for P1128, P1130 as:

• – Air intake leaking.
  – Fuel pressure too low.
  – Fuel injectors contaminated (carbonized).
  - Fuel supply volume too low.

But, this is not all-inclusive. A Vacuum leak past the MAF can also create a lean condition as could a faulty MAF.

Since you hear a hissing, check first for vacuum leaks, also check the 'j' tube of the AOS as these have been known to collapse and crack. This too could introduce un-measured intake air (do you have any smoke at startup?)

If the MAF indicated too much air (I say indicated because a failing MAF can send this signal even though that's not the case), then again the DME would try to compensate and the O2 sensors would see a 'too rich' sample.

Also, you fail to mention MY. It is also possible that a clogged fuel filter could also throw this code, though probably the least likely cause.

[23109VC]

the hissing noise is what makes me think it is a vacuum leak too.

i'm not really sure how I check for this. i guess i can look around for something that is hissing really loud if the engine cover is off? i don't really know what to look for.

i may just take it to the dealer and let them look at it.

i don't want to waste my time messing with the MAF if that's probably not it. i found the instructions online for removing/cleaning the MAF - but since my car is hissing - it would make sense that THAT is probably the problem. i'd look at vacuum leaks FIRST, and then if there is still a CEL later - then consider the MAF.

is there an easy way to check for a vacuum leak? i saw an online diagram of the intake system and it looks like a spider web of tubes, etc. i wouldn't know where to start.

at least I know it's nothing catastrophic, and I can have some peace of mind that a day or two at the dealer will result in a quick fix.

i could also use this opportunity to ditch the dealer (who the former owner used / my dad) and find a nice independent porsche mechanic closer to where I live. my dad lives 5 min from the dealer - but 40-50 miles from ME. there is no close by dealer. i'm sure there is an independent guy closer than that!

prices are probably more reasonable too.

[mookarma]

For future reference, any autozone and most advance/discount will read the codes for you for free, and some are kind enough to print you out a code report for your car. IMHO, Pep Boys is about as worthless an enterprise as has ever been created. I'd return the code reader and get my $80 back

[heyjae]

Don't forget to check the oil cap. It might be the vacuum leak. Seriously, it may just be loose.

But based on your description, (at least on my S) there is a thin tube that goes from the intake manifold to the area behind the air box. I believe it attaches to the fuel pressure regulator. That tube simply slips over the fitting, so it could come loose very easily. It could be that.

I believe the vacuum tube to the EVAP system comes from the driver's side manifold as well.

[23109VC]

is it pretty easy to get the engine cover off and get at the motor? i've never tried to do it.

i have all the manuals/etc.. i believe the instructions are in there. i'll have to take a look at it and see if I cano bviously see anything leaking..

[Mike_Yi]

Originally Posted by 23109VC

is it pretty easy to get the engine cover off and get at the motor? i've never tried to do it.

Yes. It's quite easy.

[Samson]

Originally Posted by 23109VC

is it pretty easy to get the engine cover off and get at the motor? i've never tried to do it.

Yes, it is very easy. The procedure outlined in the manual takes about 2 minutes, and no tools or anything special is required. The "hardest" part is popping the ball joints off of the top, and with those, just apply light pressure and they'll pop right off.

[shaman1204]

I got a check engine light on my 2001 with about 35or 36k miles. Same codes as you, checked all available resources on the web and figured I would try cleaning my MAF. You have to buy security torx if you are going to do this, I found them at Advance Auto Parts. Cleaned the MAF, disconnected my battery for 15 secs to clear the light and it didn't return. Until about 2k miles later. The car seemed to throw the light when I was in stop and go traffic in hot weather w/the AC on. I checked the codes again, P1128 and P1130 and was going to take it to the dealer, but the light went off while driving a few days later.

Took the car to the dealer for unrelated matter and they informed me I needed a new oil filler flex neck and clamp. My warranty didn't cover "hoses or rubber parts" so I declined the fix and would try to tackle it myself. I found the spring clamp on the oil filler tube that attached nearest the engine was kind of crooked and the tube was not snug. I took some channel locks, took the spring clamp off, pushed the tube all the way on and replaced the clamp with a screw-down type (or whatever they're called.) It is my opinion the dealer could have taken 5 seconds and fixed this, but told me I needed a whole new oil filler flex neck for the tune of $350.

No CEL to this day, knock on wood. I would check for vacuum leaks before doing anything, it could be something simple as what I had.