Thread: Car runs rich and surges at an idle?

Results 1 to 12 of 12
  1. #1 Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Ever since my turbo, cam, 65# inj install my car has ran extremely rich and surges at an idle. Could the surging and running rich be a related issue? I am hoping that maybe I have a bad maff or a bad O2 sensor. Does anyone have any ideas? I don't think I have a vac leak because my trims are negative.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

  2. #2 Re: Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    I swapped out the maff with a different one that is known to be good and it didn't change anything. The car seems to surge really bad when the a/c compressor tries to engage. If I turn the HVAC off it doesn't seem to surge much at all.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

  3. #3 Re: Car runs rich and surges at an idle? 
    GTX Level Member MTXGTP's Avatar
    Join Date
    Dec 2007
    Location
    wamego,KS
    Posts
    479
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    check the IAC motor just a thought
    Justin Young, Kansas
    1999 silver GTP DHP pcm,3" Cattless hogan DP,Front PLOG,3.4 pulley, ported TB, ported LIM, ported supercharger housing.porting done by GBP
    coming soon: LS6 springs ,1.9rr
    Reply With Quote  
     

  4. #4 Re: Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Ok here is the update. I swapped out the IAC motor, the Maff and installed a Maff screen and now the car seems to not surge near as much as it didn't before. It now bounces between 800-1000 rpms compared to 500-2500 rpms like it was doing. Does anyone think that maybe the maff screen could have caused this. The car seems to idle rough still but I am not sure if it just seems that way because of the polly dogbone mounts I am running. I guess I will know if it has leaned out or not tomorrow when I get a chance to hook PT up to it.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

  5. #5 Re: Car runs rich and surges at an idle? 
    DUI BABY Bio248's Avatar
    Join Date
    Jan 2008
    Location
    MILWAUKEE
    Posts
    31,340
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    why are you running rich at idle? there is no reason to. its almost better for you to run lean at idle.
    Reply With Quote  
     

  6. #6 Re: Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    After I installed the mods in my sig I my car was running so rich that I couldn't get any KR (this was running a stock tune other than the IFR table being adjusted for the 65# inj). My trims were -10 or more at times. I really had no idea why either. I ever tried pulling fuel via the maff table and the IFR table but I should have been adding fuel not taking it away. I don't want my car running rich but it is.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

  7. #7 Re: Car runs rich and surges at an idle? 
    DUI BABY Bio248's Avatar
    Join Date
    Jan 2008
    Location
    MILWAUKEE
    Posts
    31,340
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    sit down with a tuner and take some time to make it right. otherwise your car will run like **** because the tune is ****.
    Reply With Quote  
     

  8. #8 Re: Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    I am really hoping it is the tune and I plan on playing with the tune some tomorrow.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

  9. #9 Re: Car runs rich and surges at an idle? 
    GXP Level Member Zef_66's Avatar
    Join Date
    Dec 2007
    Location
    PA
    Posts
    2,084
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Quote Originally Posted by Andrew_99GTP View Post
    After I installed the mods in my sig I my car was running so rich that I couldn't get any KR (this was running a stock tune other than the IFR table being adjusted for the 65# inj). My trims were -10 or more at times. I really had no idea why either. I ever tried pulling fuel via the maff table and the IFR table but I should have been adding fuel not taking it away. I don't want my car running rich but it is.

    Running rich, and running a -10 fuel trim are two different things. Running rich means that your AFR is too low and you are running more fuel than you should. A -10 fuel trim means that your tables are commanding more fuel than necessary to keep the car running at the desired AFR. You need to adjust your VE table and you MAF table to account for this accordingly. If you are running rich, you need to change the desired AFR.
    2001 GSE
    Reply With Quote  
     

  10. #10 Re: Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    I guess I just assumed that I would end up adding fuel from a stock tune instead of taking it away.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

  11. #11 Re: Car runs rich and surges at an idle? 
    DUI BABY Bio248's Avatar
    Join Date
    Jan 2008
    Location
    MILWAUKEE
    Posts
    31,340
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    realistically it depends on how well your setup flows. its not really dependent on mods with how much fuel you need. there are a ton of heavily modded guys that run way leaner than my car ever will.

    wideband homie.
    Reply With Quote  
     

  12. #12 Re: Car runs rich and surges at an idle? 
    GTX Level Member Andrew_99GTP's Avatar
    Join Date
    Dec 2007
    Location
    New Salem, ND
    Posts
    763
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    I do have a wideband, I just assumed there was something wrong with my car because I was needing to pull fuel.
    Red 2dr 99 GTP"Old" Z7 t66, A/A IC'd, Custom Heads, 65# Inj, ST2 Cam, Meziere Elec Pump, JP Double Roller(with machined crank gear), Plogs, PLX W/B, Powrtuner SOLD

    "New" 2007 Duramax ccsb with a few mods
    Reply With Quote  
     

Similar Threads

  1. Need some help folks, car starts, runs, then dies
    By SyntheticShield in forum 3.8L V6 Supercharged (L67)(L32)
    Replies: 86
    Last Post: 01-14-2010, 05:48 AM
  2. Rich Condition HELP!
    By Incomudrox in forum 3.8L V6 Supercharged (L67)(L32)
    Replies: 5
    Last Post: 12-29-2009, 04:51 PM
  3. Rough Idle
    By Red_GTP in forum 3.8L V6 Supercharged (L67)(L32)
    Replies: 12
    Last Post: 02-27-2008, 02:29 PM
Tags for this Thread

View Tag Cloud

Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •