Bad MAF Sensor Symptoms: 10 Common Signs

[@ajayb2478]

I got a P0171 code on my 2005 Vauxhall Astra H. My car idle drop and cuts out intermittently when coming stop or pressing the clutch

[@HonestMechanicChannel]

Your Vauxhall Astra H showing a P0171 code indicates a "System Too Lean (Bank 1)" issue. This error suggests that the engine is receiving too much air or not enough fuel, leading to an imbalance in the air-fuel mixture. This can cause the car to idle poorly and even stall, especially when coming to a stop or engaging the clutch, as you've experienced. To address this issue, consider the following steps: Check for Vacuum Leaks: One of the most common causes of a lean mixture is a vacuum leak. Inspect all vacuum lines and intake hoses for cracks, wear, or disconnections that could be allowing extra air into the system. Inspect the Mass Air Flow (MAF) Sensor: The MAF sensor measures the amount of air entering the engine. If it's dirty or faulty, it could report incorrect air flow data, causing the engine to run lean. Cleaning or replacing the MAF sensor may resolve the issue. Examine the Fuel System: Low fuel pressure or a failing fuel pump can also lead to a lean condition. Check the fuel pressure to ensure it's within the manufacturer's specifications. The fuel filter and injectors should also be checked for clogs or malfunctions. Oxygen Sensors and Air-Fuel Ratio Sensors: Faulty sensors can send incorrect data to the car's computer, affecting the air-fuel mixture. Use a diagnostic scanner to check for any sensor-related fault codes. Check for Exhaust Leaks: Leaks in the exhaust system before the oxygen sensor can cause the sensor to read a lean mixture incorrectly. Inspect the exhaust manifold and gaskets for any signs of leaks. PCV Valve and System: A malfunctioning Positive Crankcase Ventilation (PCV) valve or system can cause a lean mixture by introducing incorrect amounts of air into the engine. Check the PCV valve and its associated hoses for blockages or leaks.

[@gvanys]

Can you use Autozone sensor for nissan rouge?

[@davemarwood1614]

My vivaro 2,0 had a few issues then stalled on me and wouldn’t start. Symptoms leading up to this were hard start, puffed out white smoke and rich smell. Pulling off in 1st on incline under load van would shake. I’ve changed the fuel filter and put a new battery and starter motor on, van starts now and very little smoke but still getting the shaking, code coming up for maf , should I replace this or try to clean with a spray? Or would it be better to replace the air filter first. I’ve not had the van long and according to the receipts a service was done 4000 miles ago, I would presume a new air filter was fitted.

[@HonestMechanicChannel]

Hi Dave, Given the symptoms and the code for the MAF (Mass Air Flow) sensor, you should: 1. Check and replace the air filter: It's an easy and inexpensive step. Just to be certain. 2. Clean the MAF sensor: Use a MAF sensor cleaner spray. This can resolve issues without needing a replacement. 3. Replace the MAF sensor: If cleaning doesn't help, then consider replacing it. Shaking under load can be due to a faulty MAF sensor causing incorrect air-fuel mixture. Start with the air filter and cleaning the MAF sensor, then replace the MAF sensor if needed. Please let me know how it goes!

[@davemarwood1614]

I changed the maff and it sorted my issues straight away, all the lights disappeared and the violent shaking has disappeared,! Thanks for your help

[@maxmax-lu1hm]

hello, can you tell me if my car has map,maf or both. my car is FORD C-Max (DM2) 1.8 Benzin 125 PS / 92 kW 2009 QQDB

[@mackpowerev1092]

2016 Toyota Corolla consistant check engine light...plus, i occasionaly see slightly shaky engin.. Do you think i should attempt cleaning the mass air (if yes, how do i need to clean it?) or just replace it with a new one

[@HonestMechanicChannel]

Hi, First, read the check engine light code to identify the issue. If related to the mass air flow sensor, try cleaning it with a specialized MAF sensor cleaner before replacing. If cleaning doesn't resolve the problem, then consider replacement.

[@marcusmaximus451]

Good idea or you can also try using WD40 electrical contact cleaner 👍👍

[@butterflysmile348]

Do not use wd cleaner!! You are giving wrong advice.

[@marcusmaximus451]

@@butterflysmile348 no check it out it is perfectly safe for electrical components I have done my research first 👍👍

[@chartmann43]

My 2010 ford transit Connect seems like it’s idiling too fast? Would that be the MAF?

[@daleduberry1635]

My truck hesitates and shakes when picking up speed between 40 and 60 would that be the same thing

[@HonestMechanicChannel]

Hi, yes that's a possibility too, when last you checked your spark plugs and coils?

[@daleduberry1635]

@HonestMechanicChannel I changed coils last summer an coils along with it I was told that I had knock off coils..I was gonna tryto clean maf before buying alot of stuff not needed...or should I just replace the maf sensor it's an 08

[@HonestMechanicChannel]

I recommend that you try to clean the sensor first before replacing and see how it goes. let me know

[@daleduberry1635]

@@HonestMechanicChannel ok thanks I'll do that Thursday and see how it goes

[@brianpedersen6282]

I brought my Volvo V60 D4 2.0 from '15 to a couple of mechanics after it started losing power at low RPMs suddenly while driving in hot weather, in hills/mountains for a few hundred km. I've checked Boost Charge Valves, cleaned MAP sensor, Boost sensor, visually checked hoses for leaks (I hear no difference). The readings I get seem alright/normal. Regardless of the gear, at low RPM I just see bad performance, like no horses are home. Above ~2.500 RPM I get all 181 horses released in one go. I got error codes, P2262, while a few more were present, I didn't see them. First mechanic immediately said "New low pressure turbo, aka new turbo, money plz" within 10 minutes with the computer on it - didn't even drive it. This guy said the other codes happened because of P2262. Second mechanic took it for a test drive, put the computer on it and said it could be the MAP sensor - after I explained it had been replaced, they said "MAF sensor then". These guys said P2262 could be triggered by the bad MAF. Is it normal that a bad MAF sensor will _only_ and _always_ affect the low RPMs? I think it's quite pricy and I would like to make sure before buying.

[@HonestMechanicChannel]

Hi there, It's normal for a bad MAF sensor to affect low RPM performance, but it's unusual for it to "always and only" affect low RPMs. The error code P2262 indicates a turbocharger boost pressure issue, often pointing to problems with the turbocharger system rather than the MAF. Before buying an expensive part, ensure the MAF is indeed the culprit by cleaning it or using a known good sensor for testing. Consider also checking the turbo control solenoid, EGR valve, and the intercooler for issues that could affect boost pressure. Please let me know how it goes!

[@brianpedersen6282]

@@HonestMechanicChannel That's how I felt. Thank you for confirming it as well. I actually got lucky, finding one at a scrapyard not far away. Drove there and tried out the MAF sensor, but unfortunately it didn't do anything. I guess I'm heading off to a Volvo workshop and have them diagnose it proper :)

[@klinton1339]

Helloo, i have a vw passat 1.9 tdi 2006 and i think that maf sensor is the problem, the question is do i need to buy a maf sensor only for passat or any regular 1.9 sensor????

[@williamwarrenconkright3973]

look at the part number on the maf…. hint put cruise control on while climbing a hill. if maf no good cruise control will not boost power to go up the hill. it will fall out of power. if maf is good cruise going up a hill ssy 50 mph will hold 50 mph all the way up the hill. at least this has been my experience 2001 vw jetta tdi. 5=speed manual 1.9

[@cabotom13]

I dIsconnected the MAF and the car kept running. But when we re-connected the MAF the car shut off on my 2005 Jaguar S Type 3.0 6cyl So what's the possible prognosis? Thanks!

[@soundsolutions]

My 2002 V8 Ford Fairlane has a rough idle, and it seems to lack power and backfires on acceleration. No codes tripped. I've cleaned the MAF with sensor cleaner spray.... also the throttle body, new spark plugs and coils. Any suggestions?

[@Hugalay]

Get a new maf sensor at autozone and install it, if it does not fix the problem return it. Sometimes you just need to replace the part

[@elcomandante9299]

Fairlane? Thought those went extinct in the 60s..

[@a_reptiledysfunction5267]

It’s the wallet that says ‘Bad MAF sensor’

[@tealmountaintrekking6141]

Say MAF again! Say. MAF. again!

[@tommitoh]

My 2015 S400L is vibrating randomly when stop. When step on accelerator lightly, it vibrates hard. If step harder, car sudden surge and goes smooth until coming to almost complete stop, car start vibarting again. Change, plugs, ignition coils, o2 sensor. Same problem persist. Vibrate, extremely bad FC (25L/100km), lack of power. However ECL doesnt shows MAF, its always something else

[@sandyteffeteller8551]

Could be crank shaft /throttle/or cam Shafter censor

[@HonestMechanicChannel]

I agree with @sandyteffeteller8551 but also I think its best to check the following as well. Engine Mounts: Worn or damaged engine mounts can cause vibrations as they fail to properly isolate engine movements from the chassis. Fuel System Issues: Given the extremely bad fuel consumption (25L/100km) and lack of power, there could be a fuel delivery problem, such as clogged injectors or a malfunctioning fuel pressure regulator. Air Intake System: Check for leaks or obstructions in the air intake system, including the MAF sensor, which, despite not showing up as a direct fault, could be affected by related issues causing performance degradation. Exhaust System: Restrictions or damages in the exhaust system, including the catalytic converter, can lead to performance issues and increased fuel consumption. Did you manage to solve it?

[@marioprofka8568]

Same issue here, it was one of the engine mounts

[@zaibi999]

I have same issue did u find any solution?

[@tommitoh]

@zaibi999 yes. One champion workshop installed my crank pulley wrongly. Did not follow the marker. Hence all the misfiring

[@hoodrichesstimeeatne]

would this cause a random cylinder misfire? I have all these symptoms

[@HonestMechanicChannel]

Hi, Yes, a bad Mass Air Flow (MAF) sensor can indeed cause random misfires. The MAF sensor measures the volume and density of air entering the engine, which is crucial for the engine control unit (ECU) to calculate the optimal fuel mixture. If the MAF sensor is faulty, it might send incorrect data to the ECU, leading to an improper air-fuel mixture. This can cause the engine to run lean (too much air in the mixture) or rich (too much fuel in the mixture), either of which can result in misfires along with other symptoms like rough idling, a decrease in fuel efficiency, and a lack of power.

[@bradwhite7351]

Great video and thank you for the info. I just replaced my MAF on my 98 toyota tacoma sr5. She runs rough now. Sputters, stalls, running very rich. I could damn near watch my fuel gage go down. I did what i researched. Disconnected battery for 30 min. Put new one in. Didn't touch the film. The break in phase is unreal. If i turn on AC at low speed 5 mph, the truck will die. I'd appreciate some guidance. Thank you

[@HonestMechanicChannel]

Hi Brad, Thanks for the comment! It's hard to tell for sure, do you have an OBD? here is what I recommend: 1. Check for Proper Installation: Double-check that the MAF sensor is properly seated and that all electrical connections are secure and clean. Make sure there are no air leaks around the sensor or in the intake system. 2. Inspect the MAF Sensor: Although the sensor is new, it’s worth inspecting it to ensure there's no accidental contamination or damage to the sensor film. Sometimes even new parts can be faulty or get damaged during shipping. 3. Reset the ECU: Since you've already disconnected the battery, consider doing an ECU reset by disconnecting the battery again and pressing the brake pedal or horn to drain any remaining electricity in the system. This can help the ECU recalibrate to the new MAF sensor. 4. Check for Codes: Use an OBD-II scanner to check for any diagnostic trouble codes (DTCs) that might indicate other issues affecting performance. 5. Inspect Other Components: If the problem persists, consider checking other related components such as the throttle position sensor, oxygen sensors, spark plugs and fuel injectors, which can also affect the air/fuel mixture and engine performance. Please let me know how it goes, Goodluck!

[@bradwhite7351]

@@HonestMechanicChannel I'll definitely let you know. I appreciate your thorough response so much! Thank you

[@elcomandante9299]

The problem is not the sensor. The problem is its a Toyota.

[@FabioSeagal]

Sound sluggish moving barely it almost dies when you first start in the mornings with if at traffic light it's hard to pull out for a Honda early in the morning

[@HonestMechanicChannel]

Yeah that can definitely be a symptom of a bad MAF sensor for sure. I would like to hear more to be sure.

[@MoistPenguinz0Clips]

So many shared symptoms with camshaft position sensors. Trying to figure it out 😖 , got the p0341 for cam pos sensor, but looks like it could have been stored as light has been on for a while, and car has probably 1/2-3/4 its original performance, but the biggest issue is starting, will die 2-3 times on first start of the day sometimes. Or not at all

[@levibogard3902]

2005 wrx sti idles rough and usually almost dies at stop lights, plus black smoke from exhaust

[@HonestMechanicChannel]

Sounds like your 2005 WRX STI is running rich, meaning too much fuel is being burned. Check for leaky fuel injectors, a dirty or faulty mass airflow sensor, or issues with the oxygen sensors. Also, inspect the air filter and spark plugs. Addressing these could resolve the rough idle and black smoke.

[@jovo21]

​@@HonestMechanicChannelcan a bad/dirty maf cause a misfire at idle and when accelerating but not when at regular road speeds?

[@scottysblog7317]

I think my MAF is bad on my 04 Pontiac grand prix. My check engine light is on, it has sluggish acceleration, and occasionally it won't start unless I lightly mash the gas. Also check gas cap light is on. Even though the cap is on as tight as it will go. Neighbor did a code read for me, it says MAF or mass leak. MAF sounds like mass, I don't know what one he meant.

[@HonestMechanicChannel]

Hi Scotty, Given the symptoms and code read, it's likely a bad MAF (Mass Air Flow) sensor. The sluggish acceleration and difficulty starting are common signs. Try cleaning the MAF sensor first. If the problem persists, consider replacing it. Also, check for any vacuum leaks which can cause similar issues. The "check gas cap" light could be related to an EVAP system leak. Make sure the gas cap is in good condition and properly sealed.

[@talahel5250]

Mazda cx5 in drive and reverse it shakes. Park the car is running fine. Im drive low rpm it shakes and after drives smooth What can this be? I already cleaned throttle and replaced injectors but still the same

[@HonestMechanicChannel]

Hi. The shaking in your Mazda CX-5 when in drive or reverse, but not in park, and particularly at low RPMs, could be due to several potential issues: Engine Mounts: Worn or damaged engine mounts can cause the car to shake when in gear but be smooth in neutral or park. Engine mounts support the engine and transmission, and if they're failing, they can't properly dampen engine vibrations.

[@emigrant4life]

Bad maf in 80% do not give the check engine light

[@lario1030]

Yes so true replacing mines but had no check engine light

[@laquayclark1802]

Thank you. I don’t know why no one has said this.

[@emigrant4life]

@@laquayclark1802 because this sensor can work, but give incorrect data, instead of 2 grams of air, it shows 3.5 grams for the ECU - and that's it, your engine is not working well, but there is no error, because the sensor works (in general). and the ECU cannot know whether the sensor provides correct data or not. It will know only when there will be no data or they will be cosmic (1000 grams/s of air, for example).

[@2dogstwodogs458]

​@@lario1030replaced mine also, and no check engine light until the car died,...

[@Peter_RFlynn]

True but does throw a P010400 code on VAG ECUs

[@peterrudy9207]

Would have been nice to include the proper cleaning of it .

[@deliriousthat5563]

Get maf cleaner. Spray it 12-15 times and let dry

[@panicc122]

BMW shakes when idling at a complete stop

[@HonestMechanicChannel]

Hey what engine does your BMW have?

[@panicc122]

@@HonestMechanicChannel m54

[@enriqueponce9132]

My BMW starts at acceleration and is stable but when it goes down to idle it shakes a lot and dies, it shows random misfire on the scanner, do you think it is the MAF?

[@386Romeo]

@@enriqueponce9132frl samex