Jump to content

Have it running smoother but........


scooterh72
 Share

Recommended Posts

Found a pretty good vacuum leak that I fixed and the car doesnt cough and sputter any more but I have noticed one thing.

 

When Im driving say at 30mph it feels like the car is surging forward. Not very smooth at all. I also noticed that when I was setting timing,

the timing mark actually moves, jumping backwards (retards I think) a little while idling. Could this be caused by a worn out distributor? Vacuum advance

is good.

 

Your guys thoughts?

Link to comment
Share on other sites

remove all the vacuum hoses on the throttlebody except one for the vac. adv. and cap all the rest and drive again.

 

Leaking BOV will do this too. Higher rpms and steady throttle there is enough engine vacuum to suck open slighty most BOVs especially those DSM ones and you are leaking out a large volume of air that has been metered. Check it, hold the rpms around 2500-3000 steady and place your hand over the BOV and if you feel any air leaking you need to correct that. Every time you just slightly lift the throttle that will suck open even more, a BOV has no reason to be doing this and most are because their springs are way too weak.

Link to comment
Share on other sites

remove all the vacuum hoses on the throttlebody except one for the vac. adv. and cap all the rest and drive again.

 

Leaking BOV will do this too. Higher rpms and steady throttle there is enough engine vacuum to suck open slighty most BOVs especially those DSM ones and you are leaking out a large volume of air that has been metered. Check it, hold the rpms around 2500-3000 steady and place your hand over the BOV and if you feel any air leaking you need to correct that. Every time you just slightly lift the throttle that will suck open even more, a BOV has no reason to be doing this and most are because their springs are way too weak.

I am not running a bov

Link to comment
Share on other sites

So I probably still have some vacuum leaks.......

 

The car wants to cough and sputter until it warms up a bit. Is this normal. I do have a new cts. Car will idle up around 1500 rpms when first starting.

Thanks again for the help.

Edited by scooterh72
Link to comment
Share on other sites

 Share

×
×
  • Create New...