Stall during acceleration

So I've had this happen a few times over the past several months. During acceleration, it feels like my foot slipped off the gas pedal. No check engine lights, no noises, it just slows down for a couple seconds. I take my foot off the gas pedal, then press it again and off she goes like nothing ever happened.

It's a 2009 w/107k miles. Any ideas?

 

I would put it on my scanner and check throttle position while moving foot on and off and look for dead spot. Just a thought. Good luck!

 

No. I was accelerating getting on an on ramp

 

Have you checked pending codes? If not I would.

 

No. Never had a check engine light. Would it still throw a code?

 

Maybe the throttle plate is sticking, you could check and clean the throttle body.

 

Yeah, a pending code is something that the computer knows is happening but it hasn't happened enough times for it to think it is an issue. After a certain amount it would throw it and turn on the light, in so many words. A pending may be what your problem is but it hasn't happened enough for it to trigger. Just something easy to check before banging your head against the wall with other stuff. It could be a lot of things.

 

10-4. Thanks a bunch

 

It sounds like your accelerator interlock programming is kicking in, either from your foot on the brake pedal, or a faulty or misadjusted brake pedal switch.

 

Mine has done this intermittently for the last few months - it usually happens after backing out of the drive , push on the go pedal and nothing happens for a couple seconds , then it takes off hard and has left rubber a few times . Did it again several times at stop lights and still no codes or pending codes . Hard to trust when it's going to accelerate in traffic and quite aggravating . I'm pretty sure it's either the pedal , throttle plate or ecm....dealers have no clue of course .

Sarge

 

Now that I think of it my 2009 was doing that every couple months. I assumed something like the fuel pump was showing signs of trouble but never did figure out what it was. (That was the first thing that came to mind because the fuel gauge stuck and I ran out of gas once, and it only took 16.8 gallons to completely fill.)

It would do it more after the battery was unplugged so maybe it really was something in the ECU. Always seemed to happen while still in first gear so yes, those wonderful dunlop tires would want to leave rubber on the road when the motor finally kicked out torque.

 

I had this problem. Ended up being the brake light switch on the brake pedal assembly was loose. Every once and a while the switch would close and turn on the brake lights. This would also tell the truck's computer you were applying the brakes thus the computer overrides the acceleration. Check the switch, it can we adjusted by turning it a quarter turn, then sliding it forward or back against the brake pedal arm, then turn it back a quarter turn to lock it back into place. Mine wasn't snug against the pedal arm.

 

Awesome! I will check that. Thank you

 

No prob, the trick is to adjust the switch so it stays off when the pedal is not being pressed, but activates just when the brake pedal is pressed enough to start slowing the truck. Mine was just on the very "edge" between "on" and "off" when the pedal was not being pressed.

 

I'll have to look into that , sounds interesting . Were the '08 models equipped with the brake interrupt ?
Sarge

 

^^ all 2nd gens were as long as they had the "gas pedal chop" recall done.

 

Ok - my pedal is a normal length - no chopped off so I assume there is no brake interrupt ...? I know I can torque load by holding the brake and using the throttle - think drag strip launch .. Or , as I call it - spring wrap maximum thrust test .
I can only imagine what the rear driveshaft looks like when doing that . Great way to test wrap , though .

Sarge

 

It sounds as though the recall is still outstanding on your truck. However, the new programming works differently in different scenarios. If you press the brake pedal FIRST, the throttle is not limited. However, if you press the brake AFTER the throttle is pressed (IIRC, over 30%), the engine will smoothly return to idle. You would still be able to do the above "spring wrap maximum thrust test" with the new programming.

 

That's what I wondered - figured it has to be a timed potential mod to return the engine to idle when brakes are applied to a certain percentage . I was taught to drive with both feet , so it's no big deal . I just want the damn thing to respond to pedal input like it should and not have this intermittent hesitation . It's gotta launch the driveshaft or rear springs one of these days , it hits it that hard as you don't have time to register that the pedal input just had no result - before the engine reacts and launches to that throttle setting . It's almost like doing a neutral drop on an auto trans without revving the engine first and usually from reverse to drive scenario is when it shows up .
Sarge

 

All I can say is Drive-By-Wire is a POS.