21 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHP1128 + P1130 error code opinion
Leading reported evidence
Clean maf about a year ago
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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Discussions that performed work without a confirmed outcome
1
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Leading evidence: 'Clean maf about a year ago' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check air oil separator' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
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Performed · outcome unconfirmed
I put in the old cleaned MAF and confirmed the ho loss...
Clean maf, throttle body and filter and all is excellent
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
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Performed · outcome unconfirmed
Recieved a P1130 about a month ago, cleaned the MAF, Throttle body and filter and all is excellent.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Performed · outcome unconfirmed
I had the same codes - first replaced the 02 sensors and then it came back - MAF needed replacing.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
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Suggestion
Sometimes even though you clean the old MAF and it feels good it's running leaner so a dyno session with AF reading was in order to ensure I was running within spec...
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
21 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
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Generation: 20261027T000231Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
I have been having P1128 + P1130 (always at the same time) error code go off on a regular basis. Only goes off when the car is sitting at a light, or stuck in slwo moving traffic. Never at higher RPM highway driving.
I don't have any leaks, haven't had a chance to ck the oil separator bellow yet. Cleaned the MAF about a year ago.
Time to clean MAF again? Or is this a symptom of the bellow going bad? Or maybe even cracked exhaust...
TIA
Robin - here is some info. Cleaning the MAF only takes a few minutes so it may be a good place to start. Also, a search on "1128" will provide a bunch of info.
GL
make sure you oil cap is on the right way and its tight.... I had these exact 2 codes after I played around with my oil cap... turned out it was loose and was letting air in....
pretty sure that if you get 2 codes at the same time its either your oil cap loose or some type of a leak in the funnel that the oil cap sits on... check it out.
Thank you guys for the input. I know I am not really running too lean as the exhaust tips are carbon up pretty good.
Oil cap is on nice and tight, the oil filler tube looks good too. Engine bottom bone dry, I do need to get it on the lift to see if I can see the bellow.
Th frequency varies, if I don't get stuck in traffic or sit in idle too much the light doesn't really go off for a long time. But if stuck in traffic too much light goes off once every couple of days. I have the scan Tool II hooked up all the time, so I just reset it on the fly, the engine doesn't feel any different, there is no hic up, or rough idle prior to throwing the CEL.
I had the same CEL codes twice now on my 99 996 over a period of several months. The first time I came off the highway and was sitting at a long light. I deleted the codes and they reappeared about 3 weeks later. I once again erased the codes and they have not come back.
Recieved a P1130 about a month ago, cleaned the MAF, Throttle body and filter and all is excellent.
Also added some Techron to the fuel tank to clean up the injectors.
Does anyone know how to troubleshoots the MAF and the O2 sensors? I've already gone through cleaning of air filter and MAF, and codes keeps coming back. I don't want to just throw money at sensors, I'd like to verify first...
Thanks!
Robin: Do you have the ability to read sensor data, fuel trim or o2 sensor signals?
Granger : What years your car, what kind of car. What faults are you getting, how are you reading them. You really should start your own thread
In addition to checking for intake leaks, including oil filler tube and cap, check your electric changeover valve connections. Valve closes and opens at startup and stays closed from 3100 - 5200 rpm. During those engine speeds, if the hose returning to the resonance flap is disconnected or otherwise leaking, it will generate these 2 codes.
I had this same problem when my shop,accidentally over oiled my k&n filter...
I replaced with stock filter to trouble shoot and then realized there was filter oil on the MAF... I cleaned and cleaned and even after the cleaning it felt like I got 40ho back the codes came back
I bought a new Bosch MAF sensor from autopartsway.com to troubleshoot and what I found was interesting indeed.
Because the MAF was contaminated with oil the car was running leaner and losing tons of ho.... I headed to the dyno with new MAF and stock paper filter and I made 12 more hp with the new MAF.... Sometimes even though you clean the old MAF and it feels good it's running leaner so a dyno session with AF reading was in order to ensure I was running within spec... I put in the old cleaned MAF and confirmed the ho loss... I then switched back to the new MAF and wanted to test the k&n filter....NO HP difference..... My car is a 99 3.4 running a GIAC flash so maybe it doesn't like the extra air because it did t show up on the dyno!!!
I'm now running with stock paper filter and new MAF and problems solved.
How old is your MAF? Do you have a stock or k&n filter?
Here
https://rennlist.com/forums/996-foru...omponents.html
Valve #1 is the valve for the intake resonance flap. The valve gets vacuum from the vacuum reservoir and supplies it to the flap actuator to change the intake resonance.
How do I access the vacuum lines. Do I remove the alternator and even then my hands go nowhere near the lines and Y junctions. Is there a way from behind the rear seats or from under the rear end? Hopm eyou can help me out here Ashia. Thanks.
This is a source reference. Confirm exact model applicability in the original material.
