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DSC _might_ be the link between the brake pedal making the gas pedal go cold. If this is true, then turning the DSC off should solve the problem temporarily. It's a valid test, that's for sure.

The problem with left foot braking in a stick shift, beyond resting the foot on the brake pedal enough that the brakes drag, is that if one is actively braking and the need to change gears arises, then the feet have to dance. If there is a rapidly approaching tree, then the foot dance can be the difference in hitting or missing the tree.
If there is a tree approaching that quickly BOTH feet should be on the brake :lmao:
 

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My Toyota truck has a recall (that I never had installed) to update the software to make the brake override the throttle. This was done because of too many incidents of the throttle by wire basically going hay wire and causing unintended acceleration.
 

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Hello, here is an update: I believe to be a solution.
After re-reading all of the responses, I went back to make sure there was no SES light on or other clues.
I used an Advance Auto ODBII scanner with the key on, engine off and got no active codes, pass. HOWEVER, I tried reading the codes with engine running and got a single fault code, P0101 MAF fault circuit range /perf. code "pending".
This raises more questions...
Is keeping the engine from being revving up the "limp" mode behavior for my 330?
For anyone who experienced an MAF sensor going bad, does it happen quickly? One day it works and the next it does not?

Before I plug a $400+ part in, is there any checks I can do to the car/harness. Dont want to plug in and burn a new sensor.
Is there anything I could have done to damage the old MAF sensor? unplugging it with battery connected?
I will try and clean the old sensor and test it. I saw lots of posts on MAF testing...
Any further suggestions?
Thanks for everyones help.
Cant think how the MAF could be damaged by unplugging it, might be worth 'tightening' the electrical contacts in the MAF plug. This thread discusses the pigtail connectors used on the MAF plug etc, OP claims that 'adjusting' the pins inside them can do wonders:

http://forum.e46fanatics.com/showthread.php?t=856781
 

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Discussion Starter · #24 ·
I had that problem once and thought it was a security override then I changed my control arm bushing and e-brake shoe and it started to work on its own along with cruise control
Hello Eniaro, Do you have more information about changing the e-brake that has fixed the issue with no gas pedal on this thread?
 

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Discussion Starter · #25 ·
Hello.
I have a 2002 330CI convertible. M54 engine series. Manual.
This car does not have a cable for the throttle. Drive by wire.
Symptoms:
Start car, no SEL lights or diagnostics.
With car in neutral or in gear, clutch pressed or not, I can rev the engine, good response. idle is also good.
The moment I press the brake pedal, the accelerator no longer revs the engine.

Short background. Car ran well before this. I replaced the air filter. Changed the oil. I did disconnect the MAF while replacing the air filter. But was very sure to reconnect it. However I did not disconnect the battery.
When this happened the first time I did get the DSC light to come on. Was backing up on a slight incline.
To make this go away I restart the car, the gas pedal revs the engine well.
the moment I hit the brake pedal it disable the gas pedal.
I need some help. Thank You Lucas330CI

Also wanted to add that once the brake pedal is pressed the engines stays in perfect idle. around 750 rpm ( approx)
I have tried disconnected the battery for several minutes and reconnected.
2nd update: Brake pedal disables gas pedal.
Disconnected battery. 20 min. Reconnected.
Started car, accelerator works. Manually Shut off DSC ( light on), accelerator works, touched brake pedal, accelerator disabled.
Re-started the car. accelerator works.
I am still getting the MAF P0102 fault. After second or third start the SES light came on, and MAF code is active.

Followed instructions from various posts on testing MAF.
The cable to the MAF checked well, not shorted to ground, 14 vdc with car on, yellow wire back to computer has 4.7K ohms to ground. Wires not shorted to each other or to ground. Confident MAF cable is good. Also checked pins and connections.
With MAF connected and car tunning, I put sewing needles through the wires just before the connector and measured 14 vdc on the red, and 0.07 vdc on the yellow.
Per some other posts, this is very low, and this voltage does not change when engine is revved up.
With this, I will declare the MAF bad.
I have ordered a new OEM Siemmens. Should be here next week.
I have searched the bentley manual and there seems to be many reading comparisons from MAF to throttle control. The only place on the manual that talks about loss of throttle control due to a fault has to do with DSC. At this moment I do not believe the DSC is the cause.
Looking back at the events that led to this situations, If I had lost the MAF reading during the last time the car ran, and by resetting the computer by disconnecting the battery, could that have lost and throttle to MAF data?
Does anyone else experienced an MAF fault cause this loss of throttle control?
I may not be getting all the codes with my advance auto ODBII scanner.
Can anyone recommend a pc based tool that is capable of reading codes in more details, and have more powerfull diagnostic tools etc...
Thanks in advance for your time and information.
 

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If there is a tree approaching that quickly BOTH feet should be on the brake :lmao:
Not true. The clutch foot should not be on the brake, that's the only true condition.

If you have 3 pedals, then use the left foot on the left most pedal and no others. If you have 2 pedals, leave the left foot firmly planted on the floor.

One may encounter a special circumstance from time to time that causes you to break the rule, but it's impossible to address the corner cases. The main rule is that the left foot should never ever be on the brake pedal.
 

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Discussion Starter · #27 · (Edited)
The problem was fixed with the new MAF.

With Battery disconnected, installed new MAF, re connected the battery, Car stuttered upon start for a few seconds, then got smooth idle. Revved the engine, good response, touched, and released the brake, and gas pedal no longer disabled.

A few lessons learned on this issue for me...

1) On a manual transmission 330CI, keeping the engine at idle when an MAF fails, is a little harsh of a design. One is able to move the car to a safe location away from blocking traffic, if the road is flat and with very careful slow release of the clutch. HOWEVER, This does not work if car is on a hill. There is simply not enough power at idle speed to get the car to a safe location.
2) Learned that my generic scanner does not pickup all of the BMW codes. Ordered a Creator C110 ODB2 Fault Code Scanner. I will leave it in the car.

3) I will buy a second MAF ( not as expensive as OEM ) and keep it in the car. It will get the car running if it fails again. Especially since it failed without much reason or warning.

Thanks for everyone's help. Thanks for E46Fanatics Forum.

Now, researching a xenon headlight that is not working. Thanks.
 

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All of this suddenly makes sense (sort of). I replaced my MAF sensor 2 weeks ago and never associated that with the brake no longer disabling the gas as it used to. Why this occurs with a bad MAF I have no idea. I was amazed last week when I went out to test it and my brake did NOT disable the gas. Interesting...
 

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Well I want to add my experience because it seems to indicate that other things can cause the brake pedal to disable the gas pedal. I***8217;d been experiencing this problem for a really long time. I***8217;ve had a couple DSC wheel speed sensors become flaky. I replaced one and still had the issue. I saw my speedometer go out a couple times and in another thread I saw that was likely the other rear speed sensor. So I bought that one but hadn***8217;t put it in when I needed to get my SES light shut off so I could pass inspection. Codes showed a Mass Airflow problem and a Camshaft outlet sensor code. Based on the consensus it was the mass airflow sensor, I bought a new main sensor and a secondary. No change. Just finished changing the camshaft outlet sensor and resetting my SES and the problem is fixed. I***8217;m so relieved. Was really getting worried. Hope that helps someone!!
 

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Hello.
I have a 2002 330CI convertible. M54 engine series. Manual.
This car does not have a cable for the throttle. Drive by wire.
Symptoms:
Start car, no SEL lights or diagnostics.
With car in neutral or in gear, clutch pressed or not, I can rev the engine, good response. idle is also good.
The moment I press the brake pedal, the accelerator no longer revs the engine.

Short background. Car ran well before this. I replaced the air filter. Changed the oil. I did disconnect the MAF while replacing the air filter. But was very sure to reconnect it. However I did not disconnect the battery.
When this happened the first time I did get the DSC light to come on. Was backing up on a slight incline.
To make this go away I restart the car, the gas pedal revs the engine well.
the moment I hit the brake pedal it disable the gas pedal.
I need some help. Thank You Lucas330CI

Also wanted to add that once the brake pedal is pressed the engines stays in perfect idle. around 750 rpm ( approx)
I have tried disconnected the battery for several minutes and reconnected.
There is a DTC 78 plausibility accelerator and brake pedals that appears when you press the accelerator and brake pedal at the same time so clearly the DME program sees this as a problem as well it should. It is not logical to do both nor is it good for the car. So the computer is going to defend the car from that kind of abuse.
 

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Disconnecting the MAF is known to cause the brake pedal to disable the gas pedal. So the MAF is where I'd look

There is a DTC 78 plausibility accelerator and brake pedals that appears when you press the accelerator and brake pedal at the same time so clearly the DME program sees this as a problem as well it should. It is not logical to do both nor is it good for the car. So the computer is going to defend the car from that kind of abuse.
Ever hear of heel-toe downshifts? That error code shouldn't trigger unless it's detecting both inputs for an extended period of time.
 

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Ever hear of heel-toe downshifts? That error code shouldn't trigger unless it's detecting both inputs for an extended period of time.
Been driving manual cars and trucks for 49 years. Never found it necessary to do a heel-toe downshift and never will.
 

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Been driving manual cars and trucks for 49 years. Never found it necessary to do a heel-toe downshift and never will.
It's not necessary technique on the street, but it is a valid technique, and is something that a car billed as being performance oriented should handle (and can as it happens to be - OP has an error condition, not intended behavior).
 

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Been driving manual cars and trucks for 49 years. Never found it necessary to do a heel-toe downshift and never will.

Each to their own. But part of the joy of driving a BMW hard is to get it
to the point where using a bit of left foot brake just makes instinctive sense...
...and settles the car nicely.

t
also has driven tractors.
And 2002's with shot 2nd gear synchros.
Both teach you things.
 

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Why? They invented synchro so you wouldn't have to.
Not all truck transmissions have synchros, but for those you just shift by sound without a clutch. Around here when you take the road test for a commercial license they want you to double clutch eah gear. The truck I tested in only had 9 gears.
 

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Guys, it was solved with the MAF. No need to convince us old farts we drive wrong, and no need for us old farts to tell anybody else how to drive.
But... but.... then we wouldn't be FANATICS!!!!!

t
fan-at-ick
 
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