P1128 and p1130 codes
 

Hi, everyone new to the forum. I bought my wife a 2001 Boxster S. The issue I'm having is the car is giving me these codes. It runs great, I've cleaned the MAF. Still get the code. When the weather gets a bit better I'll get out there and do more checking. I guess what throws me off on these codes is that all the post I've seen with them they have bad running cars. This one runs great except with the check engine light. Any thoughts would be helpful. Thanks.

Check your Air Oil Separator, it might be bad.

Had the same codes a few years ago...car ran rough when first started
 

and engine was cold (overnight). I eventually took it to a indie euro mechanic that deduced that it could be the AOS (had recently been replaced), Air leak, MAF, or that the engine was defective. The last response about the defective engine is what let me know they had no clue what they were doing and did not have the necessary equipment to do diagnostics on the car. I bought a new MAF a few weeks later and the codes never came back and the car ran smooth again. The car will run without the MAF hooked up so it does give some trouble shooting insight as to whether the MAF is good or bad.

9/10 times it is a failed MAF or intake air leak. Start there.

I have had those codes intermittently for quite some time. Can't really notice performance issues. I can't find a pattern but it was after an AOS failure w oil in throttle body. Cleaned MAF and throttle body. Haven't noticed performance issues. Got tired of booting up the Durametric so I got one of the Bluetooth ELM units and just read and reset it w android phone. I suspect vacuum leak bug have been unable to track it down

Agreed. I had the same issue with the check engine light coming on. Same codes, but the car ran just fine. Would reset the codes and would be ok for about a month and then come back on. Instead of just cleaning the MAF I bought a new one off of Amazon. Got the Bosch MAF. Spent an hour installing it and that fixed the problem.

Same codes after Throttle body clean. For me it was improper re-seating of AOS to Throttle body hose.
It has an odd seating system on each end so make sure they seated correctly

Using your Durametric, what does the voltages look like on the O2 sensors ahead of your catalytic converters with the motor running?

Jaeger sorry did not reply sooner but was not on line. Have not checked voltage but will try to check this weekend. Would be happy if it was as simple as MAF replacement but I suspect vacuum leak.