VT SS 6.2L idle problem!

[brooksie81]

hey guys,

i just bought a VT SS with a gen lll 5.7L which has been rebuilt to a 6.2L

Drives great, however when i decellerate for a set of lights etc the engine finds it hard to idle. It will drop down to about 100-200 rpm then jump up at 1100-1200 rpm. It will do this everal times back and forward until it finds its balance at 600-700 rpm. Sometimes it will even stall during this process.

Any ideas what may be causing this and how it can be fixed ?? Even a rough idea on $$

Cheers !

[H1GHROLLR]

did you manage to get those cam specs and a pic/video mate

[brooksie81]

hey mate,

it was pissing down rain all day on the "Sunshine Coast" so no chnace of pics/vid. Had some fun though haha. Anyway i dont know where i would start with getting them cam specs. Would it be specific to the engine or would all Genlll that are rebuilt to a 6.2L be the same? In which case where do you suggest searching because i dont think the previous owner has them.

cheers

[H1GHROLLR]

i would think that if you built a ls1 to 6.2 it would be cammed up but maybe it was just built to ls3 specs im not sure mate its your car i thought maybe you knew a bit about it

[brooksie81]

nah mate, i only picked it up 3 days ago and i didnt do a great deal of research into the car before purchasing.... it was through a mate down south n ive been strapped for time. Ill get in contact with him during the week and see if he can dig up some specs n ill post them.

Just check out ur ride man looks sweet !! do you have an album of pics n vid? i couldnt find it in ur profile

cheers

[H1GHROLLR]

nah i dont only the pics in my thread mate of min and my missus clubby

[brooksie81]

sweet, n thanks for ur help, much appreciated cheers !!

[VYBR8R]

hey mate, what throttle body are you running? standard or aftermarket?
ive had this problem before, the idle adjustment screw on the throttle body comes loose and it loses its setting, all you need is an allen key to adjust it up so the throttle blade position is correct for idle. you'll find then it'll run alot better, it wont need much of an adjustment you'll be surprised just how a little turn will change. best time to do it is when the car is warm and idling you'll be able to hear the difference as you adjust- if you need help finding the screw look where the accelerator cable attaches to the throttle body, under it will be a screw. any problems pm me

[brooksie81]

thanks champ, i got no idea about the throttle body but i finally had the chance to look under the hood at it today (i only bought it a few days ago) im gonna have a play around with that grub screw tomorrow but it seems to simple, i think there is more to it. When it does idle its on about 700-800 which is what it shiuld be yet the problem still occurs. i think if i raise the idle to 1000 it would help a fair bit. BUt putting that aside it shouldnt have to be up that hugh anyway. i spoke to a mechanic today he said it needs a tune but thats gonna be like $900 plus, im sure there is a cheaper way !!

[VYBR8R]

hey mate, let me know how it goes, but what you described to me is exactly what mine was doing. i felt like an idiot when i took it to my tuner and he pulled out the allen key and fixed in 2 twists lol
in regards to tuning, you can adjust the idle without having to dyno tune the whole car. my tuner mitch at WA performance did it in 10 minutes at the drag strip one night with a laptop so if you could find someone with LS1 edit or VCM suite they should do it for you if you need it for bugger all. do you know who tuned the car when the stroker was done? i had a 383 in my last car a VX SS but had heaps of problems with it. goodluck mate

[enhancedss]

As mentioned in an earlier post, you can give the throttle stop a small adjustment, if that doesnt work take it and spend the dollars and get it tuned.

Cheers Brad

ps. where abouts are you located?

[VYBR8R]

Howd you go sorting your VT out mate??

[v8commy]

oi mgiht sound wierd but my mums car does the same thing her abs control module is dodgy so when you slow the car revs all over the place and at the light the revs pulse for like 10-15 secs then it finds its place

[VYBR8R]

how do you know the abs control module is dodgy? sounds very weird lol

[brooksie81]

hey guys,

I've been flat out, im gonna have a play around under the hood tomorrow. Took it into my mechanics and he recommended the tune too but im convinced there is a cheaper option. Ill post tmorrow night once ive had a good look at the problem. In addition i just had the exhaust changed to a quieter system because it failed roadworthy and it slightly changed the idle problem, it doesnt fall as low as often. Its still annoying but not as bad... but i dont understand how that would have changed much. Anyway thanks for all ur advice ill get back to u all tomorrow

Cheers

[v8commy]

had it checked out coz idle control motor was fine so thought wtf electrician reckens abs module weird hard to find the same one to suit as well coz there not all the same

[Solid8]

In reference to the original post, you dont have a SS Inductions throttle body do you mate?

[96SEN8R]

Mate, if you want brad to solve your problem, send him your ecu and a few pineapples and your donk will come back mckey mouse, otherwise, imsorry to say, brad hasnt got time to give few addvice. Im sure your car is sweet. but brad has 1 of the best shops in sa and he is running it by himself. so send your ecu and your laughing, otherwise your as et as sending it to your local profix

[96SEN8R]

Mate, if you want brad to solve your problem, send him your ecu and a few pineapples and your donk will come back mckey mouse, otherwise, imsorry to say, brad hasnt got time to give few addvice. Im sure your car is sweet. but brad has 1 of the best shops in sa and he is running it by himself. so send your ecu and your laughing, otherwise your as et as sending it to your local profix

haha dont know what i was on about last night.. had a few to many drinks:P sorry fellers

[383VXSS]

O2 sensors?

[crumpet hunter]

is it auto if so maybe the convertor is to big for the cam send your cam specs to some on that bilds convertors and thay can help you

[minux]

Moved to VT section, please look when post a thread, this has nothing to do with site sponsors...

[Cobez]

hey guys,

I've been flat out, im gonna have a play around under the hood tomorrow. Took it into my mechanics and he recommended the tune too but im convinced there is a cheaper option. Ill post tmorrow night once ive had a good look at the problem. In addition i just had the exhaust changed to a quieter system because it failed roadworthy and it slightly changed the idle problem, it doesnt fall as low as often. Its still annoying but not as bad... but i dont understand how that would have changed much. Anyway thanks for all ur advice ill get back to u all tomorrow

Cheers

Wait, correct me if i am wrong, but you buy a VT SS that's been stroked out to 6.2, yet you want a "cheaper" way to fix this problem?

Providing it IS the tune that needs to be fixed up, just save the cash and have it dyno tuned. You will get the most out of your engine stroke and mods, whilst correcting your problem. The power and torque increase will be quite significant.

I had my internally stock VS Senator dyno tuned on a Dyno Dynamics dyno using Kalmaker gear for the software upgrade. Midrange picked up heaps, so did the torque and it runs as smooth as silk.

You could also have a vacuum leak. Mine was idling up and down and almost stalling a week or so ago, turns out my fuel pressure reg vacuum line on the manifold was split and causing the shit idle, replaced the hose, runs beautiful now.

[H1GHROLLR]

Wait, correct me if i am wrong, but you buy a VT SS that's been stroked out to 6.2, yet you want a "cheaper" way to fix this problem?

Providing it IS the tune that needs to be fixed up, just save the cash and have it dyno tuned. You will get the most out of your engine stroke and mods, whilst correcting your problem. The power and torque increase will be quite significant.

I had my internally stock VS Senator dyno tuned on a Dyno Dynamics dyno using Kalmaker gear for the software upgrade. Midrange picked up heaps, so did the torque and it runs as smooth as silk.

You could also have a vacuum leak. Mine was idling up and down and almost stalling a week or so ago, turns out my fuel pressure reg vacuum line on the manifold was split and causing the shit idle, replaced the hose, runs beautiful now.

complete agree with you there mate once you start playing with cam/heads and storkers it is never going to cheap as a stocker proberly the worst thing you can start doing is trying to do things cheap in the end it will cost you big time

[Cobez]

That's what i thought! The last thing i'd be worrying about on a 6.2 litre stroker is "cheap".

Don't drive it until you have the the $900 for the tune. Dyno tuning it will probably be one of the best things you will do. Mine is an internally stock 304 and i thought it picked up really nicely after a dyno tune, in fact i love it, i can only imagine how yours will go after a tune.

Will be like a new car.