LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Wtf...idle /start up issues help

Thread Tools
 
Search this Thread
 
Old 04-21-2009, 08:57 PM
  #1  
TECH Veteran
Thread Starter
iTrader: (246)
 
robsquikz28's Avatar
 
Join Date: Mar 2008
Location: Chicago/Crown point
Posts: 4,987
Received 0 Likes on 0 Posts

Question Wtf...idle /start up issues help

ok its a 96 lt1 and ive had this issue ever since i have gotten a bbk 52 throttle body and a tune....they were both done the same time so i cant break down whether its the tune or the t.b.

either way i have adjusted the t.b blades to be slightly open and the tps volts is at .67 then 4.57v at wot.

i reset my iac several times thinking it could be it and i used my bros known good iac and checked the length of the iac (rod) motor and its the same on both and the counts do go down but havent got that far yet...to see how low they actually go

its starts up like **** and idles like at 600rpm and the only way i can get it to go up to atleast 1000rpm is to give it gas for a bit then it will idle just fine but it will take a bit...then i can turn it off and restart the same **** runs like ***....and it may take a very long time to start as well as if its flooded and i have to almost clear flood it to start....any suggestion would be greatly appreciated...

i think its the t.b but idk im just upset...

thanks

Last edited by robsquikz28; 04-22-2009 at 11:30 AM.
Old 04-21-2009, 09:16 PM
  #2  
TECH Veteran
 
BALLSS's Avatar
 
Join Date: Apr 2008
Posts: 4,904
Received 87 Likes on 78 Posts

Default

put the 48 mm back on...if problem goes away...your choice as what to do next.

what you describe is VERY common with aftermarket TB's. Been there and done that which is why I had the stock TB bored to 52

you can get the 52 to work...well work better...but you will need a scan tool to measure IAC counts and then do the drill mod. You may get lucky by just opening up the blades 1/4 turn but typically that throws of TPS (you can do the dance of sloting out the holes but..)

if it were me I would sell the BBK and get the stock one bored to 52, just my $02
Old 04-21-2009, 11:24 PM
  #3  
TECH Veteran
Thread Starter
iTrader: (246)
 
robsquikz28's Avatar
 
Join Date: Mar 2008
Location: Chicago/Crown point
Posts: 4,987
Received 0 Likes on 0 Posts

Default

i have already drilled it and i have the scanner and watched iac counts for a bit and the throttle blades are open slightly
Old 04-22-2009, 11:03 AM
  #4  
TECH Veteran
Thread Starter
iTrader: (246)
 
robsquikz28's Avatar
 
Join Date: Mar 2008
Location: Chicago/Crown point
Posts: 4,987
Received 0 Likes on 0 Posts

Default

wow nobody has any ideas or what
Old 04-22-2009, 03:00 PM
  #5  
TECH Veteran
 
BALLSS's Avatar
 
Join Date: Apr 2008
Posts: 4,904
Received 87 Likes on 78 Posts

Default

Originally Posted by robsquikz28
i have already drilled it and i have the scanner and watched iac counts for a bit and the throttle blades are open slightly
...well than how big a hole?

what are the IAC counts?
Old 04-23-2009, 11:55 AM
  #6  
TECH Veteran
Thread Starter
iTrader: (246)
 
robsquikz28's Avatar
 
Join Date: Mar 2008
Location: Chicago/Crown point
Posts: 4,987
Received 0 Likes on 0 Posts

Default

ok well right now the iac counts are 60-68
ect is 180*
afr 14.7
idle at 900
this is with a cam too.

on cold starts its shitty but as it warms up it goes away and starts better and quicker...mainly just the cold starts its crappy



Quick Reply: Wtf...idle /start up issues help



All times are GMT -5. The time now is 04:24 PM.