vacuum is terrible and idle is bad :(

[StarCraftLover]

hi,

anyone that can help, id apperciate anything i can get

my friend helped me replace my oil pump after i got it diagnosed at mitsu and all seemed well until we started the car...

the vacuum always sat ~ 16, but now it sits at ~ 5 and the car has a real unsettling idle. lots and lots of vibration

my friend owned an 6 bolt gst, and said that one of his friends experienced the same type of problems when his balance shafts were bad.

what should i do to diagnose this new problem?

 

[andymoraitis]

I would start by doing the simple things first like checking to make sure that all of your vacuum lines are plugged in properly and not leaking. You can test these by running the motor at idle and spraying individual lines with carb & choke cleaner. A change in idle would indicate a vacuum leak. Bad balance shafts wouldn't affect vacuum since the pumps are gear driven off of the front cover.

Also, take a moment to make sure that all of your sensors including the TPS and ISC are plugged in properly. Sometimes it's just little things that make a mess.

Let us know what you find,

Andy

 

[jott5555]

your timeing may be off.. really when you were in there you should have just eliminated the balance shaft its such a simple easy process to do... but you need to check your timeing and make sure its on.. then look for boost leaks thats another thing that will cause you to be loseing air.

if your not fimular with how to make a boost leak tester check out www.vfaq.com and look under intake,

 

[andymoraitis]

Jott has an excellent point. Having the gears off a few teeth will really screw with vacuum. Good job bro!

Andy

 

[4BangR-x]

umm wont having the cam gears off more then one tooth cause a little more of a problem then a bad idle.

 

[Talesin]

Think you can jump two teeth before you start risking a bent valve... but yeah, skipped timing was the first thing that came to my mind too.