Acceleration hesitation

[Eliot_Ness_Ls]

Can someone explain more of this PCM flash? I had asked a few dealerships about this and they all tell me it cant be done.

My dealership suggested the Chevron and it sucks, it did nothing and a few other Mechanics told me its not good for the ls.

 

[glanga]

they just plug your car in and reflash the car's computer right? like erasing the hard drive on a comp and reloading it all up again? any ford dealer should be able to do this. I've had to do it numerous times on my V since the previous owner did a bad power program.

I'd just get the SCT and that'll get rid almost all the tranny lag. Try that first before you go replacing parts or fixing stuff that isn't broken. Plus you'll get some extra kick out of it.

 

[macboy]

There is NEVER a weird pause as you slow from say..30-18, then need to instantly floor it.

That's isn't a problem on the LS either, at least not on mine (an 06 like the OP). I find that if I floor it (from a roll), or just press the gas far enough to accelerate aggressively, then the trans instantly downshifts to a gear that puts the engine up to around 4500 to 5000 rpm, right in the power range. The car takes off like nobody's business. But if I accelerate (from a roll again) less aggressively, the trans stays in 5th and the engine bogs down at around 1900 to 2000 rpm for around a second, then goes to 4th for about 1/2 second, then goes to 3rd finally, reaching about 3500 rpm which is about right for the amount of acceleration I am asking for with my foot. The car gets it right eventually but it takes way too long to get there. My 02 Sport did not do this. It was much much less reluctant to shift gears when accelerating. The problem is entirely with the computer that controls the shift points.

 

[Ch1ll1ng]

I somewhat get this problem also. It's a 2001 V8 non sport.

I have to push the gas pedal in about maybe an inch and a half to get the car to acclerate from a dead stop. It just feels like the gas pedal is a bit soft.

I'm also having a problem starting the car where it takes a few seconds for the engine to start. I'm thinking it is probably a bad battery but combined with the soft pedal I'm thinking maybe I need my injectors cleaned. I havent had a chance to test the battery, I just got the car last night and am work right now. Any advice?

 

[lseguy]

Not the coils. When a coil misfires, the RPM will DROP hard and fast. Stumble even.

You are experiencing a fully functioning LS Automatic transmission. Poor design. My 1999 automatic GM built transmission in my BMW M3 is MUCH more precise. Shifts quickly, perfectly, EVERYtime. You can even slightly feel it automatically downshift to the lower gear when you slow down..so it's already in the proper gear in case you want/need to nail the accelerator. Even more so when you have it in "sport" mode vs the normal "economy" mode.

FYI: Someone on this forum is working on some sort of software that he SWEARS will fix all of these issues. My instinct tells me otherwise, as the PCM engineers told my long ago that the lag is due to hydraulic issues at work

 

[BlazeWW420]

When I go full throttle at 30 to 50 mph. The engine revs as if im barely pushing the gas and the car pick up speed and then the engine goes full throttle and puts the power down. There's no check engine light and no pending fault codes or verified ones. Could ot be the intake itself. I heard that in some lincolns there are two paths in the intake. One for slower driving or cruising and the other for acceleration. If my 2003 LS V8 has that could it be the cause and if not then what could cause it without a trouble code?

 

[joegr]

...I heard that in some lincolns there are two paths in the intake. One for slower driving or cruising and the other for acceleration. If my 2003 LS V8 has that could it be the cause and if not then what could cause it without a trouble code?

The V8 does not have this.