engine really rough
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Joined: Apr 2001
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From: NW FL
engine really rough
I cannot get my engine smooth. I have just installed a new 350 in my car and when i turn it over it can idle but it is very rough and shakes a lot. I adjusted my timing and got it about as good as it could get by turning the distributor i also unconnected the EST when i did it. I am very sure that all my spark plugs are one tight but i have been wrong before so i will check that in the morning but what else could do that because i don’t know what to do.
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Joined: Dec 2000
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From: Raleigh, NC, USA
Vacuum leaks will cause a rough idle, so check all your lines. It's probably the cheapest fix, so, why not?
Check your idle air passageways, when they get clogged it can cause poor idle as well.
While you're at it, set/adjust the IAC and TPS. That can cause poor idles too.
A bad EGR valve can cause a rough idle, although unfortunately it's about 80 bucks.
A radical cam can also produce a rough idle, but I"m guessing you would've known about that if you swapped cams. heh
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89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else
Check your idle air passageways, when they get clogged it can cause poor idle as well.
While you're at it, set/adjust the IAC and TPS. That can cause poor idles too.
A bad EGR valve can cause a rough idle, although unfortunately it's about 80 bucks.
A radical cam can also produce a rough idle, but I"m guessing you would've known about that if you swapped cams. heh
------------------
89 iroc-z 305 tbi
k&n filtercharger, open element air filter. nuffin' else
Thread Starter
Senior Member
Joined: Apr 2001
Posts: 935
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From: NW FL
That is all very true. I checked to see if i have any vacuum leaks all around and don’t think i do. This is a new engine with mostly new parts on it. And it does not have an EGR, i just plugged the vacuum port, is that how you do it? And i really wish i had a rough idle because of a big cam 
. Oh yea how do you set/adjust the IAC and TPS i really don’t know and if someone could tell me how i would appreciate it.
Thank,
Danny
. Oh yea how do you set/adjust the IAC and TPS i really don’t know and if someone could tell me how i would appreciate it.Thank,
Danny
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Joined: Dec 2000
Posts: 886
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From: Raleigh, NC, USA
https://www.thirdgen.org/newdesign/tech/tpimod2.shtml
There ya go. hehe. If you have any further questions just ask.
There ya go. hehe. If you have any further questions just ask.
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Joined: Apr 2001
Posts: 935
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From: NW FL
: eek: 
i was looking thought the tpi set up that i have in my garage and found out it has the same clip as my new tbi and i noticed something else... i had the wires back words i had the wires black blue white when there soposto be reversed. i had to make my one clip because i couldnot find another and asked someone what was the order and they told me backwards or he just took it off and having it faced towards him read the colors i did the colors when it was plugged in looking from the back where the wires come out!! Oh well i have to check it again to see if it will idle worth anything but i think that should help a lot
i was looking thought the tpi set up that i have in my garage and found out it has the same clip as my new tbi and i noticed something else... i had the wires back words i had the wires black blue white when there soposto be reversed. i had to make my one clip because i couldnot find another and asked someone what was the order and they told me backwards or he just took it off and having it faced towards him read the colors i did the colors when it was plugged in looking from the back where the wires come out!! Oh well i have to check it again to see if it will idle worth anything but i think that should help a lot 
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