17 throttle lunge

Hoginedgewood · June 22, 2019

2017 5.3 when cold, easing the throttle to leave the driveway, I get a lunging,, not just once, probably about 500 rpms. I know it's not the pedal. Couple months left on warranty.

BO TIE 1 · June 22, 2019

I just started having this same issue on my 2018 5.3. I put in some fuel line cleaner, no help. Yesterday filled up with some 89 octane to see if that helps. Gonna give it some time to run thru. Hoping it's not transmission related. Seems to have some similarities to the torque converter issues I've read about. I've checked to see if there are any codes being thrown but not seeing anything. Just hate to take it in and have them tell me they couldn't replicate the issue. Post up if you get this sorted out.

1SLOW1500 · June 22, 2019

Well very interesting. You start by saying cold then you say around 500rpm. I don't know exactly what cold means but if engine and ambient air temp is low or cold the pcm should set for 900rpm idle and your in gear(each different) also has a setting.

Sound like a pain but remote start it get in and look at the ect engine coolant temp if over 180* all tables shift and normal drive settings should be there. You will also know quickly as in idle the rpms should be much lower.

Is there a catch can and how many miles. Sounds like the service bulletins.

CamGTP · June 22, 2019

My 2016 does this when it's cold enough and I don't care at all.

You notice it right away if you only took like 5-10 seconds to start and slap it in gear to start moving. There is a lot going on with the calibration on cold starts to try and achieve the emissions standards, so the computer is doing some funny things to bring up cylinder temps and exhaust temps as quickly as possible. You'd see rich fueling and negative timing to get it going and I've noticed it tends to make the throttle really touchy.