I am getting sick of replacing the MAF
#1
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uuuugghhhh .... I have been getting the double ABS and PSM and then today the check engine light with codes P1126 and P1133. I just replaced the last MAF about 2 1/2 years ago. How long is the life of these MAF?
#5
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Roughly 80K miles later engine started acting up a bit and traced problem to "new" MAF. On a hunch swapped out suspect MAF and installed original MAF.
Original MAF still worked (and is working) just fine. "New" MAF had gone bad in 80K miles.
Sincerely,
Macster.
#6
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I've been getting CEL about once a week for some time; either P1126 or P1128. What these codes are communicating is that the DME can’t make the fuel mixture rich enough. Because the codes are occurring on both the left and right sides its likely not a fuel injector issue. After some research I'm in a process of doing the following:
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
Then if all this fails replace the MAF.
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
Then if all this fails replace the MAF.
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#8
Drifting
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I've been getting CEL about once a week for some time; either P1126 or P1128. What these codes are communicating is that the DME can’t make the fuel mixture rich enough. Because the codes are occurring on both the left and right sides its likely not a fuel injector issue. After some research I'm in a process of doing the following:
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
5. Install a new OEM engine intake air filter
6. Remove the MAF/IAT module and clean it. Use a Q-tip and solvent to clean (CAREFULLY) any oil or dirt from the two little glass beads you will see in the airway. One of these is a HOT WIRE air flow rate sensor,MAF, and the other is a diode used to sense intake airflow temperature, IAT.
Then if all this fails replace the MAF.
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
5. Install a new OEM engine intake air filter
6. Remove the MAF/IAT module and clean it. Use a Q-tip and solvent to clean (CAREFULLY) any oil or dirt from the two little glass beads you will see in the airway. One of these is a HOT WIRE air flow rate sensor,MAF, and the other is a diode used to sense intake airflow temperature, IAT.
Then if all this fails replace the MAF.
#9
Race Car
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I've been getting CEL about once a week for some time; either P1126 or P1128. What these codes are communicating is that the DME can’t make the fuel mixture rich enough. Because the codes are occurring on both the left and right sides its likely not a fuel injector issue. After some research I'm in a process of doing the following:
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
Then if all this fails replace the MAF.
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
Then if all this fails replace the MAF.
#10
Race Director
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I've been getting CEL about once a week for some time; either P1126 or P1128. What these codes are communicating is that the DME can’t make the fuel mixture rich enough. Because the codes are occurring on both the left and right sides its likely not a fuel injector issue. After some research I'm in a process of doing the following:
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
Then if all this fails replace the MAF.
1. Check oil cap. This I have done, I think I will replace it or see if I can find a replacement o-ring.
2. Try and put a vacuum on the intake system and see if it holds. Researching how to do that right now.
3. Replace fuel filter, will likely just do it.
4. Replace air/oil separator, expensive item will make sure 1 to 3 are done first.
Then if all this fails replace the MAF.
Cap cost $13. Do not think the problem was the o-ring. I appeared to me the problem was the cap's fingers that worked to pull the cap down and snug on the oil filler tube were just worn.
BTW, the air leaking past the cap is a lot at idle. But at engine speeds above idle represents very little of the air entering the engine so if the error codes represent failure to supply enough fuel at engine speeds higher than idle this suggests the problem is not a cap leak. It could still be a failing AOS though.
While you're there at oil filler tube cap check for excessive vacuum. One symptom when my car's AOS was failing -- before I knew what it was -- was excessive vacuum at oil filler tube. Was unable to pull the cap off against the pressure difference.
A bad AOS may not exhibit this symptom so if it is absent it is not proof AOS is ok, though.
Do not waste time trying to put a vacuum on the intake system. With the valves you won't be able to do this. Used to on engines where the intake more accessible with the engine warmed up and idling spray carb cleaner around where the intake bolts to the heads and intake ports. This was when an intake leak at one of these interfaces suspected. If a leak is present it will cause the carb cleaner to be pulled into the engine and the engine will react by speeding up or slowing down. Varies.
Others use a small bottle of propane or butane. If there is a leak the engine when it gets a whiff of the propane will react and you'll know.
If fuel filter not flowing enough fuel to engine at idle enough to trip engine controller at enrichening threshold error codes the engine should cut out at high rpms cause it can't get enough fuel to keep it running.
If cap found ok or replaced and symptom still present be sure oil filler tube not cracked. If this ok then suspect AOS.
A test for the MAF is to clear error codes -- which also resets fuel trims to 0 -- and disconnect the MAF from the wiring harness and drive the car and see if error codes return. Also, if the MAF bad enough to cause any other engine misbehavior disconnecting it can make these go away. If they go away...
IIRC there are voltage checks to use to help ID bad MAF but my tech resources are not with me and I can't recall the numbers.
Sincerely,
Macster.
#11
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#12
Racer
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What is 33? Something to do with bank 2 I am guessing. I will get the the ABS/PSM lights after lifting the gas pedal under hard acceleration.
#13
Race Car
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You can check the cap. If it is leaking it should be easy to check. With engne idling try to move the cap. Pay attention to engine. If engine reacts cap leaking. You might even be able to hear the air leaking past the cap. I did -- or I should say a co-worker heard the leaking cap on my Boxster. Moving the cap around -- just wiggling it -- one could hear the leak noise change, even go away, then return as the cap moved around.
Cap cost $13. Do not think the problem was the o-ring. I appeared to me the problem was the cap's fingers that worked to pull the cap down and snug on the oil filler tube were just worn.
BTW, the air leaking past the cap is a lot at idle. But at engine speeds above idle represents very little of the air entering the engine so if the error codes represent failure to supply enough fuel at engine speeds higher than idle this suggests the problem is not a cap leak. It could still be a failing AOS though.
While you're there at oil filler tube cap check for excessive vacuum. One symptom when my car's AOS was failing -- before I knew what it was -- was excessive vacuum at oil filler tube. Was unable to pull the cap off against the pressure difference.
A bad AOS may not exhibit this symptom so if it is absent it is not proof AOS is ok, though.
Do not waste time trying to put a vacuum on the intake system. With the valves you won't be able to do this. Used to on engines where the intake more accessible with the engine warmed up and idling spray carb cleaner around where the intake bolts to the heads and intake ports. This was when an intake leak at one of these interfaces suspected. If a leak is present it will cause the carb cleaner to be pulled into the engine and the engine will react by speeding up or slowing down. Varies.
Others use a small bottle of propane or butane. If there is a leak the engine when it gets a whiff of the propane will react and you'll know.
If fuel filter not flowing enough fuel to engine at idle enough to trip engine controller at enrichening threshold error codes the engine should cut out at high rpms cause it can't get enough fuel to keep it running.
If cap found ok or replaced and symptom still present be sure oil filler tube not cracked. If this ok then suspect AOS.
A test for the MAF is to clear error codes -- which also resets fuel trims to 0 -- and disconnect the MAF from the wiring harness and drive the car and see if error codes return. Also, if the MAF bad enough to cause any other engine misbehavior disconnecting it can make these go away. If they go away...
IIRC there are voltage checks to use to help ID bad MAF but my tech resources are not with me and I can't recall the numbers.
Sincerely,
Macster.
Cap cost $13. Do not think the problem was the o-ring. I appeared to me the problem was the cap's fingers that worked to pull the cap down and snug on the oil filler tube were just worn.
BTW, the air leaking past the cap is a lot at idle. But at engine speeds above idle represents very little of the air entering the engine so if the error codes represent failure to supply enough fuel at engine speeds higher than idle this suggests the problem is not a cap leak. It could still be a failing AOS though.
While you're there at oil filler tube cap check for excessive vacuum. One symptom when my car's AOS was failing -- before I knew what it was -- was excessive vacuum at oil filler tube. Was unable to pull the cap off against the pressure difference.
A bad AOS may not exhibit this symptom so if it is absent it is not proof AOS is ok, though.
Do not waste time trying to put a vacuum on the intake system. With the valves you won't be able to do this. Used to on engines where the intake more accessible with the engine warmed up and idling spray carb cleaner around where the intake bolts to the heads and intake ports. This was when an intake leak at one of these interfaces suspected. If a leak is present it will cause the carb cleaner to be pulled into the engine and the engine will react by speeding up or slowing down. Varies.
Others use a small bottle of propane or butane. If there is a leak the engine when it gets a whiff of the propane will react and you'll know.
If fuel filter not flowing enough fuel to engine at idle enough to trip engine controller at enrichening threshold error codes the engine should cut out at high rpms cause it can't get enough fuel to keep it running.
If cap found ok or replaced and symptom still present be sure oil filler tube not cracked. If this ok then suspect AOS.
A test for the MAF is to clear error codes -- which also resets fuel trims to 0 -- and disconnect the MAF from the wiring harness and drive the car and see if error codes return. Also, if the MAF bad enough to cause any other engine misbehavior disconnecting it can make these go away. If they go away...
IIRC there are voltage checks to use to help ID bad MAF but my tech resources are not with me and I can't recall the numbers.
Sincerely,
Macster.
Hooking up a vacuum gauge to the intake is simple and everyone who works on their own cars should know their normal vacuum reading as well as how to read the gauge.
#14
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P1126- Oxygen Sensor Low Adaptation, Lower load range, Bank 1
P1128- Oxygen sensing adaptation, Idle range bank 1
P1133 Oxygen sensing adaptation, Lower range bank 2
I had the ABS/PSM problem show up one time as well.
Perhaps these issues are better left to the pros to figure out...
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#15
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^^^
And so I did just that. From the ticket:
"hooked up tester. Checked fault codes. p1126, P1128, P1130, has both rich and lean fault codes. needs mafs. replaced mass air meter. cleared faults, tested system. all OK."
I will report back if CEL comes on again. And btw it was covered under my CPO Warranty.
And so I did just that. From the ticket:
"hooked up tester. Checked fault codes. p1126, P1128, P1130, has both rich and lean fault codes. needs mafs. replaced mass air meter. cleared faults, tested system. all OK."
I will report back if CEL comes on again. And btw it was covered under my CPO Warranty.