Christopher Lockett Posted December 22, 2020 Report Share Posted December 22, 2020 (edited) Just want to make sure that I'm cleaning my 94 Seville SLS 4.6 liter Northstar correctly. Throttle body that is sorry bout that. Good amount of hesitation at lower speeds make me feel like I need to step on it harder. Higher speeds also just not nearly as bad Edited December 22, 2020 by Christopher Lockett Forgot info Quote Link to comment Share on other sites More sharing options...
rockfangd Posted December 23, 2020 Report Share Posted December 23, 2020 Better to remove it. Not too difficult. Not sure if the 94 had the coolant lines to it. I know my 94 Olds did. Use TB cleaner only. Clean the throat behind the butterfly really good. I like to clean the IAC passages good as well. Do not install the TB gasket backward. Trust me it can be done. It will block one of the important ports. Someone else will likely chime in as I thought there was something more about the pre 95 TBs that was common to failure. All my Northstars have been 96+ Quote GM FAN FOREVER Nice, clean, luxury= fine automobile Link to comment Share on other sites More sharing options...
Christopher Lockett Posted December 25, 2020 Author Report Share Posted December 25, 2020 On 12/23/2020 at 1:50 PM, rockfangd said: Better to remove it. Not too difficult. Not sure if the 94 had the coolant lines to it. I know my 94 Olds did. Use TB cleaner only. Clean the throat behind the butterfly really good. I like to clean the IAC passages good as well. Do not install the TB gasket backward. Trust me it can be done. It will block one of the important ports. Someone else will likely chime in as I thought there was something more about the pre 95 TBs that was common to failure. All my Northstars have been 96+ Hey man thank you I appreciate that I just didn't know if I need to do some kind of an idle relearn or something like that once I get everything reinstalled back together Quote Link to comment Share on other sites More sharing options...
Christopher Lockett Posted December 25, 2020 Author Report Share Posted December 25, 2020 Just now, Christopher Lockett said: Hey man thank you I appreciate that I just didn't know if I need to do some kind of an idle relearn or something like that once I get everything reinstalled back together I was testing the bombs in the power going from the idle position sensor to the computer but now whenever I plug you everything back in my idle is revving about a thousand end when I rev the gas it will not hold a steady RPMs instead it goes up and down from Mega thousand back up to 1500 back down to like 1500 up to 2,000 it will not hold steady Quote Link to comment Share on other sites More sharing options...
rockfangd Posted December 26, 2020 Report Share Posted December 26, 2020 Ok. I was going to add to your last response. IIRC Disconnect battery for about a minute. Reconnect battery. Start engine and put in gear with your foot on the brake for about a minute. Shut down. Restart and do the same with all loads on, (AC, Defrost, All lights, etc...) See if it goes down. If the TB was very dirty the IAC will need to be relearned. Hopefully above will help that. Let me see if I can find the exact procedure but that usually works for me Check this page out if above does not work. http://www.caddyinfo.com/idlelearn.htm I see it is for the 4.9l . Not 100% sure it will work with the Northstar. Quote GM FAN FOREVER Nice, clean, luxury= fine automobile Link to comment Share on other sites More sharing options...
Christopher Lockett Posted December 28, 2020 Author Report Share Posted December 28, 2020 On 12/25/2020 at 5:55 PM, rockfangd said: Ok. I was going to add to your last response. IIRC Disconnect battery for about a minute. Reconnect battery. Start engine and put in gear with your foot on the brake for about a minute. Shut down. Restart and do the same with all loads on, (AC, Defrost, All lights, etc...) See if it goes down. If the TB was very dirty the IAC will need to be relearned. Hopefully above will help that. Let me see if I can find the exact procedure but that usually works for me Check this page out if above does not work. http://www.caddyinfo.com/idlelearn.htm I see it is for the 4.9l . Not 100% sure it will work with the Northstar. Thank you very much I really appreciate that it actually worked everything is back to normal as far as the idle and everything but my 94 sls 4.6 has a hesitation that I've been trying to figure out for quite some time even before the idle issue do you have any leads as far as things I could do to figure it out. I have done Plug and wire replacement I don't know how old the coil packs are but if there's anything else you can think of that I can do. I replaced the fuel pressure regulator I'm about to replace the map sensor. Thanks again for your assistance Quote Link to comment Share on other sites More sharing options...
Christopher Lockett Posted December 28, 2020 Author Report Share Posted December 28, 2020 Just now, Christopher Lockett said: Thank you very much I really appreciate that it actually worked everything is back to normal as far as the idle and everything but my 94 sls 4.6 has a hesitation that I've been trying to figure out for quite some time even before the idle issue do you have any leads as far as things I could do to figure it out. I have done Plug and wire replacement I don't know how old the coil packs are but if there's anything else you can think of that I can do. I replaced the fuel pressure regulator I'm about to replace the map sensor. Thanks again for your assistance I should probably add that the hesitation comes in whenever I am accelerating from a dead stop and persist all the way up through highway speeds and then my service light will come on sometimes and usually stays on until I shut the vehicle off Quote Link to comment Share on other sites More sharing options...
rockfangd Posted December 28, 2020 Report Share Posted December 28, 2020 Have you pulled the code when the light has come on? I wonder what your fuel pressure is. MAybe fuel pressure is low causing a starve under load. Last change of fuel filter? Quote GM FAN FOREVER Nice, clean, luxury= fine automobile Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.