The following has happened twice. The first time I blew off the problem as failing to begin stopping early enough, and having the brake nanny kick in. The second time happened yesterday, and I was definitely not coming in hot to a stop.

I have a 2003, all stock, G35 Sedan with 60K miles.

As I was coming up to a stoplight at appx 35 mph I let off the gas and began coasting. I depressed the brake pedal, and the brakes began "screaming" loudly. My car began lurching and slowly grinding to a stop. There was a 350Z convertible in front of me, and I ended up maybe 1 inch off the bumper. I had zero control in determining when the car would stop. As I sat there stopped with the brake fully depressed and the brakes still "screaming" the only thing I could think of doing was to put the car in neutral. When I did that the car bucked, the brakes stopped screaming, and the engine revved past redline (my foot was nowhere near the gas pedal). I immediately turned the car off.

At this point the 350Z moved forward a couple of feet. When I restarted the car, all was back to normal. I tried a few hard stops on the way home (away from traffic), but was unable to duplicate the problem.

Any ideas what this might be? I view this an extremely serious problem, and will need to go to the dealer or mechanic ASAP. Any info would be most helpful.

 

CHeck your floormats. I can't imagine the brake pedal increasing fuel to the car. Either way, have it checked - better safe than sorry. And No, I have never heard of this before except in the 80's. But that drivers were pressing the wrong pedal and blamed the manufacturer.

 

+1. Especially with all-weather floormats. I had situation where my all-weather floormats would make their way over the accelerator pedal. I just ended up getting rid of the driver floormat and kept just the carpeted one there....

 

The floormats are the original carpet, with the "hook" that keeps them them from sliding. I double-checked this and the floormat is secure and multiple inches away from both the brake and the gas pedals.

I'll be taking the car to the dealer on Tuesday. I spoke with the service rep tonight and he'd never heard of this kind of problem. Before Tuesday I'll stop by my local auto parts store and borrow the OBD to see if any error codes were recorded.

I guess the only good news is that I'm a whole lot more conservative when approaching an intersection

 

Good luck. Best bet would be if you could somehow duplicate the problem before you bring it to them. If they can't duplicate it, then they might not do anything to fix....

 

Definitely sounds like a sticking throttle to me, maybe a worn out cable, that would be consistent with the redline revving in neutral, and it would be hell on your brakes to both have the gas and the brake pedal down at once, hence the squealing.
Time to take 'er to the dealer.

 

+1 for lancer. I run an idependent shop and soiunds like the throttle is sticking. Car didnt stop because it was accelerating. Have the throttle checked ASAP. You wont find any OBD codes for this kind of problem. to check, check the throttle response at the engine bay. Take out the air intake hose and take a look inside the throttle and see it's dirty. Open up the throttle and spray some gum cutter and clean the blades too. Then take a clean rag, wrap it around a screw driver and clean the inside of the throttle body. very simple DIY throttle body service, shouldn't take you more then an hour. After the service when starting the car, you'll notice white smoke coming out of the exhaust or hard time starting. It's normal, it burning off the gum cutter. To avoid this problem, replace the air filter every 15k-20k mile, and check if there is a leak in the air intake system.

 

I checked for error codes this morning, and as BroDaJin suspected, there was none found via the AutoZone's OBD.

First thing I gotta admit is I'm not the most mechanically inclined person in the world. While I do much of my own basic routine maintenance on my G35 and my wife's VW Jetta TDI (diesel fuel filters are easy to drain or replace...), taking apart things which are unfamiliar often leads from DIY to BIY (break it yourself). I searched the forums for a DIY with pictures, but did not see one on how to access the TB. Tracing the air intake system from the air filter into the engine, which specific section do I need to remove to see the throttle body, or do I remove the whole air intake system?

Note that the air filter has been replaced regularly, at about 15k intervals. A visual inspection of the air intake system did not show anything obvious where an air leak may be occurring. Is there a way to determine if there is a leak?

 

there have been other reports, either on this site or my350z.

i'm going by memory here, but it was the throttle body that ended up being replaced in that other thread...

i would find the threads, take them in to the dealer, and get that taken care of under warranty if possible.

 

I thought our cars have electronic TB? There's no throttle cable.

 

that's correct.

 

There is no cable on our drive by wire setup...

 

Couldnt be a cable because infiniti uses an electric throttle body...if that is what you are talking about. I would do a ECU reset (unplug the battery for 24 hours) it might be something electrical. If that doesn't work get it to infinit asap.

-Sean

 

pretty much new here, but isn't this something that happens with a lot of drive-by wire cars? i used to own a crown vic and hung around crownvic.net, and this happened to a few d.b.w. cars there, and i've heard of it happening with other newer cars too. i think the best thing to do when it happens is to kill the car (ignition off). i would check for any shorts, or water in the throttle pedal wiring, the position sensor and such. this might seem silly, but actuating the throttle might "reset" the signal to the throttle body.

as for how to fix it, it might never happen again, but like i said, check for electrical issues first.

 

Careful with drive by wire manually forcing throttle plate or just using the wrong spray cleaner can damage system or at minimum get the plate vs pedal out of syncronization.

Study your FSM as to how to correctly approach the situation.