Fight fit

This Saturday morning I started my car when it was cold, the car started misfiring really bad and bogging out really bad. I scan my car just see what was wrong even when the check engine light was not on. I got a code P0101 Air mass volume air flow range performance. I took to a friend that’s mechanic he hooked it up to his machine and its says that Cylinder 7 is not working its always at 157 even driving or idling. So he said it was the Spark plugs and wires, so changed that and it didt fix the issue. He cleaned the Maf sensor that was not the issue he said its working. So checked the coils all coils work and and then he thought it could be injector so he switched the injector and that was not a issue, he checked fuel pressure and that was fine. The only thing they didn’t check was the compression test to see of cylinder so I need to take it to another shop. Has this ever happen to any of you guys and what was the fix. One guy said if can be valve spring but the car has about 70K miles on the car. Any experts that can help me with this. The only code is the P0101 Air mass
04 GTO Headers straight pipe, Throttle body, KN air filter.

dw456post

Well, P0101 is a MAF sensor code. Maybe the serpentine belt got into the MAF wiring harness?

Fight fit

Will this cause cylinder 7 not to work. I know im leaking power sterring fluid so the belt squeaks really bad very highh pitch buut the belt looks good still. The mechanic checked the maf sensor and he said its working fine. If it wasnt working all the cylinders will not be working right he said.

psiconversion

iTrader: (5)

Did you check the air filter for an obstruction ? Here are the symptoms for that code.

- Engine Light ON (or Service Engine Soon Warning Light)
- Engine stall
- Engine running rough
- Excessive fuel consumption
- Excessive smoke

Fight fit

yes all of those symptoms is what i have but he checked to see if the MAF was working and it is. However the K&N air filter one of the sensor that plugs in looks really lose its still pluged in the filter. I dont think that would cause #7 to stop working. Engine does all and misfires, stall super rough sounds like a it has cam which it doesnt.

psiconversion

iTrader: (5)

If you have a noid light, you can check to see if your PCM is sending an injector pulse. Pink wire on injector plug should have 12 volts key on the other wire is a pulsed ground from the PCM. You mentioned a loose plug, is that on the MAF ?

Fight fit

no the lose plug goes into the k&N air filter not the MAF thats on the other side. I told the guys that was working on my car that when i spray the MAF and i start the car it seems to improve but the readings state diffrent that #7 is not working.

psiconversion

iTrader: (5)

Here is some checks you can do for P0101.

Inspect the harness of the mass air flow (MAF) sensor to verify that it is not routed too close to the following components:
The secondary ignition wires or coils
Any solenoids
Any relays
Any motors
A low minimum air rate through the sensor bore at idle or during deceleration may cause this DTC to set. Inspect for the following conditions:
Any deposits on the throttle plate or in the throttle bore
Any vacuum leak downstream of the MAF sensor
Inspect for any contamination or debris on the sensing elements of the MAF sensor.
Inspect the air induction system for any water intrusion. Any water that reaches the MAF sensor will skew the sensor and may cause this DTC to set.
A wide open throttle acceleration from a stop should cause the MAF sensor parameter on the scan tool to increase rapidly. This increase should be from 5-12 g/s at idle to 200 g/s or more at the time of the 1-2 shift. If the increase is not observed, inspect for a restriction in the induction system or the exhaust system.
Inspect for a skewed or stuck ECT sensor.
A high resistance of 15 ohms or more on the ignition 1 voltage circuit may cause the DTC to set. A high resistance may cause a driveability concern before this DTC sets.
The barometric pressure that is used to calculate the predicted mass air flow value is initially based on the manifold absolute pressure (MAP) sensor at key ON. When the engine is running the BARO value is continually updated near wide open throttle. A skewed MAP sensor will cause the calculated mass air flow value to be inaccurate and may result in a no start condition. The value shown for the MAP sensor parameter varies with the altitude. With the ignition ON and the engine OFF, 101 kPa is the approximate value near sea level. This value will decrease by approximately 3 kPa for every 305 meters (1,000 feet) of altitude.
A high resistance on the low reference circuit of the MAP sensor may cause this DTC to set.
A short to voltage on the 5-volt reference circuit of the MAP sensor may cause this DTC to set.

Fight fit

thank you i will tell the tech this. He thought it can be valve spring or cylnder ring issue

Buzzmanb12

iTrader: (11)

All the symptoms you describe sound like an air leak after the MAF... Check all your intake tubes for correct connections and no holes/splits or cracks, vacuum lines, injector O-rings and intake gaskets. One small hole can do exactly what you are experiencing.

blackbyrd

iTrader: (14)

not a ls1 car but had a similar issue once, it ended up being a squirrel packing the air intake box full of acorns for the winter......just a thought

dw456post

I was talking about the belt cutting into the maf wires. What loose sensor do you have in the K&N? Quit spraying the maf. If you have a P0101, why do you think it is #7 problem? Crank the car, pull the #7 plug off and see if it runs worse. ---Well, crank it, see how it runs, kill it---pull the plug wire and recrank and see how it runs. If you grab the wire while it is running. it will knock your dick in the dirt.

Fight fit

Ok Ill stop praying the MAf and ill check the wires like you said I do know the wire that goes in the MAF plastic peice is off the plug and im sure that since my powersterring pump is going out and leaking got some of the fluid on the maf wire. The car at the shop they been looking over the car its been 3 hours and they still can't find the issue. Depressing ! I told themwhat you guys said they are doing that but still having issues.

Fight fit

why i said #7 is becuase they hooked i up to a snapon machine and it says that #7 is not working at all. thats the only one thats not working right.

blackbyrd

iTrader: (14)

^ correct me if I'm wrong but the only thing the ECM can determine that with is a misfire. To get to that point there is a lot of other codes that would corroborate though usually starting with a o2 code. Unless they did a compression test

Fight fit

My Guess is I had a tune last year and the tune people turn off the 02 codes in the back since i did straight pipe with flowmaster mufflers. So i had codes but the tune guy took care of them. Will this affect that. No compression test yet I hope they do that in the morining. Code that I saw on mine diablo was code P101 Air mass but when the guy hooked it up it sai dthe sam thing however she did advance test and watched all cylinders and he said #7 is not working. He did a fuel pressure test and check each injector and Maf everything is working normaly.

blackbyrd

iTrader: (14)

No the tune wouldn't effect that only thing they turned off would be the rear o2 since you have long tubes . The rears measure catalytic converter effeciency and that's it.

Need your front o2's to run. It takes a huge amount of drive cycles to determine a misfire and there is a logic path to narrow down a cylinder but again it takes readings from MAF Map and your o2's to get to that point. There is no sensor that specifically monitors each cylinder

Never used a snap on scan tool but the only information you could get from the ECM would be a live feed of injector pulse per bank, timing adjustments and coil.pack firing.

Unless it's using the knock sensors to detect combustion events corresponding to firing order. The code you have though corresponds to something happening before any of that comes into play. I'd say you have an airflow issue either a blockage before the maf or an issue past it keeping the engine from getting desired airflow.

04 ls1 still ran a cable driven TB check to see if you have slack in the cable.

dw456post

Scope the cylinder to see if there is piston damage

Fight fit

hey thanks guys! just got messaged that the compression test was good.

VAredgoat

I had the same problem after my intake came lose (bad hose clamp) and the belt burned a hole in the intake tube on my k&n right where the air intake temp sensor is. The small sensor next to the maf.