VN V6 S1 rough idle and jerky driving

[lemusa]

Hey vn's playin up since its back on road. Idle can be really erratic and when driving it can jerk around a bit. quite violently sometimes. Hot or cold doesnt seem to matter and its most jerky maintainin a steedy speed, revs don't matter either I dont think. Will rev out fine and doesnt feel down on power.

Tried to get a few vids coming home but you don't really get the idea except in this one of idle, this is pretty tame but may help, ignore the rattles, havent put all the trim back in yet



Any ideas? Cheers

[CAFA_TF]

Map sensor ????look to me like its having problems identifying inlet manifold pressure, ?
then again could just be a vacuum line cracked leaking id start there dont forget to trace the one to the charcoal canister....not sure how there all set up on the original buick 3.8

[Brett_jjj]

Try checking for any error codes.---Checking your Computer for Faults (VN - VP)---

[lemusa]

sorry forgot to say i checked error codes this morning and it came back clean. it seems to have patches where its worse than others. i dont know alot about inlet pressure etc but if it was dodgy wouldnt it have a problem with foot flat reving out?

[CAFA_TF]

Generally if there is a vacume leak, when you just touch the accelerator lightly , that is when it will go to stall, and under load it will be jerky as hell down low but generally the worst is over at high rpm, just check all the thin rubber hoses running from the back of your manifold trace them everywhere they go and inspect them for cracks and leak, , this is where i would start as they will cause this and they are the first thing to generally degrade wear over time just like Leads.

[lemusa]

Ok cheers,

hoses seem to be fine, maybe a little loose fittin on the fittings though? should i be able to move it at all without to much force?