Thread: Car starts , runs rough , sometimes dies , then smooths out

Results 1 to 15 of 15
  1. #1 Car starts , runs rough , sometimes dies , then smooths out 
    SE Level Member
    Join Date
    Feb 2015
    Location
    Mn
    Posts
    5
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    I have a 04 Gtp n my car will start then run rough sometimes dying then straightens out . I've cleaned the throttle body n Maft . Seemed to help but my issue doesn't happen every time . There's no consistency when this happens also . I have no codes also. Has anybody had similar issues ? I read a few people had this issue with the older gtps but not a 04 . I also seem to get a little hesitation on wot .. Ideas ?
    Reply With Quote  
     

  2. #2 Re: Car starts , runs rough , sometimes dies , then smooths out 
    Turbo is the way to go. Fivefingerdeathpunch's Avatar
    Join Date
    Sep 2009
    Location
    Rogers, MN
    Posts
    21,022
    Thanks (Received)
    21
    Likes (Received)
    45
    Dislikes (Received)
    0
    I would have said TB and MAF cleaning are in order first, but that was done.

    Next would be to check spark plugs and replace is never done before. Never hurts to check fuel pressure either, though that seems more unlikely.


    Where at in MN, could be close to me maybe.

    SMGPFC Member #1
    Reply With Quote  
     

  3. #3 Re: Car starts , runs rough , sometimes dies , then smooths out 
    SE Level Member
    Join Date
    Feb 2015
    Location
    Mn
    Posts
    5
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Hey I'm in st. Michael , basically neighbor
    Reply With Quote  
     

  4. #4 Re: Car starts , runs rough , sometimes dies , then smooths out 
    SE Level Member
    Join Date
    Feb 2015
    Location
    Mn
    Posts
    5
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    I just had the motor out and resealed everything from rear main seal cover to valve covers , oil pan etc . I did put new plugs in but I got them from orielys and they looked them up , The car is stock also . I just took it out today and it misfired 4k and up if I floored it . Cel flashed n got code p300 ..
    Last edited by Davey1234567; 03-01-2015 at 11:55 AM.
    Reply With Quote  
     

  5. #5 Re: Car starts , runs rough , sometimes dies , then smooths out 
    GrandPrix Junkie SgtMarshal's Avatar
    Join Date
    Feb 2012
    Location
    Kemmerer, Wyoming
    Posts
    4,704
    Thanks (Received)
    10
    Likes (Received)
    25
    Dislikes (Received)
    0
    o2 sensor or catalytic converter
    Reply With Quote  
     

  6. #6 Re: Car starts , runs rough , sometimes dies , then smooths out 
    Killa Bee Scottydoggs's Avatar
    Join Date
    Aug 2010
    Location
    new jersey
    Posts
    39,927
    Thanks (Received)
    63
    Likes (Received)
    166
    Dislikes (Received)
    5
    flashing cel is misfires. clogged cat or bad plugs, maybe a plug wire is crossed up, double check them. the plugs you want to use are iridium plugs, not platinum. 3800's dont like plat's at all. if thats what they gave you. double check them as well.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
    Reply With Quote  
     

  7. #7 Re: Car starts , runs rough , sometimes dies , then smooths out 
    GrandPrix Junkie SgtMarshal's Avatar
    Join Date
    Feb 2012
    Location
    Kemmerer, Wyoming
    Posts
    4,704
    Thanks (Received)
    10
    Likes (Received)
    25
    Dislikes (Received)
    0
    I like copper core plug's better than iridium. the last set of iridium plugs I had didn't last near as long as they were advertised to.
    Reply With Quote  
     

  8. #8 Re: Car starts , runs rough , sometimes dies , then smooths out 
    Killa Bee Scottydoggs's Avatar
    Join Date
    Aug 2010
    Location
    new jersey
    Posts
    39,927
    Thanks (Received)
    63
    Likes (Received)
    166
    Dislikes (Received)
    5
    sounds like hes stock, so copper is not really needed. copper only last 15,000 miles tops. so if you dont mind a tune up every year the 3800 loves the copper plugs.

    copper core plugs are also silly cheap, less then $2 a plug most of the time.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
    Reply With Quote  
     

  9. #9 Re: Car starts , runs rough , sometimes dies , then smooths out 
    GrandPrix Junkie SDGTP99's Avatar
    Join Date
    May 2009
    Location
    Wichita
    Posts
    3,085
    Thanks (Received)
    1
    Likes (Received)
    5
    Dislikes (Received)
    1
    My guess is your problem could be a vacuum leak. Get a can of carb cleaner and spray around all of the gaskets while the car is running. I deff' second checking your plugs, cat & EGR valve. Vacuum lines too.
    OverKilled, HAI, Ported Throttle body, Ported intake, ZZP DP, Magnaflow, BMR ta's, GMPP STB's, CCS springs, tinted tailights, roof rails, TEP cool'r, G8 hood. Glass Gearbox.
    Reply With Quote  
     

  10. #10 Re: Car starts , runs rough , sometimes dies , then smooths out 
    Turbo is the way to go. Fivefingerdeathpunch's Avatar
    Join Date
    Sep 2009
    Location
    Rogers, MN
    Posts
    21,022
    Thanks (Received)
    21
    Likes (Received)
    45
    Dislikes (Received)
    0
    I have my laptop that can scan all cylinders for misfire to help determine what ones it might be, I also have a spare ICM laying around if needed for testing.

    But I agree with the other, what plugs did they sell you?

    SMGPFC Member #1
    Reply With Quote  
     

  11. #11 Re: Car starts , runs rough , sometimes dies , then smooths out 
    SE Level Member
    Join Date
    Feb 2015
    Location
    Mn
    Posts
    5
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Ok thanks for the tips guys but something bad happened today with it . I decided to do a couple more hard pulls so maybe it would set just a single cylinder misfire or just another code in general to help and in doing so the engine started knocking , sounds like I got a rod knock . When I had the oil pan off all connecting rods had alot of side to side play but not up and down . Also all seem to have about the same amount of play . So I didn't think much of it . ( when I had the engine out prior ) Question now is I have so much time and money into it since I bought it what are my options ? Can I toss some standard bearings in it ? Do people get these rebuilt ? Find s boneyard engine ? I'm thinking bout just putting it on cl and seeing what I can get ...

    - I know they were ac Delco and irdium
    Reply With Quote  
     

  12. #12 Re: Car starts , runs rough , sometimes dies , then smooths out 
    Killa Bee Scottydoggs's Avatar
    Join Date
    Aug 2010
    Location
    new jersey
    Posts
    39,927
    Thanks (Received)
    63
    Likes (Received)
    166
    Dislikes (Received)
    5
    if the bottom end is knocking the cheap way is a junk yard engine.

    you cant just slap new bearings in these engines with out machine shop work. the shop costs will cost more then the jy engine.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
    Reply With Quote  
     

  13. #13 Re: Car starts , runs rough , sometimes dies , then smooths out 
    GTP Level Member 99GT2dr's Avatar
    Join Date
    Dec 2007
    Location
    Cibolo, TX
    Posts
    545
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Pull the valve covers and make sure everything is good under there, would suck to swap the motor when it was just a broken spring/bad lifter/pushrod or something much easier. Unless you know 100% no doubt it's a rod.

    If it is, then junkyard motor without a doubt, sucks you just bought all those gaskets on your current one. I just spent close to $200 in gaskets for the L36 going in the wife's SE, **** adds up quick.
    '11 Suburban LTZ
    '99 SSEi
    '99 GT
    '09 G8 GT
    Reply With Quote  
     

  14. #14 Re: Car starts , runs rough , sometimes dies , then smooths out 
    SE Level Member
    Join Date
    Feb 2015
    Location
    Mn
    Posts
    5
    Thanks (Received)
    0
    Likes (Received)
    0
    Dislikes (Received)
    0
    Ya sounds like a rod n by looking at the balancer can almost guarantee it's a rod , engine doesn't really miss , n I think would if a top end component was bad ... But anyways what would this far be worth as is so you think ?
    Reply With Quote  
     

  15. #15 Re: Car starts , runs rough , sometimes dies , then smooths out 
    Killa Bee Scottydoggs's Avatar
    Join Date
    Aug 2010
    Location
    new jersey
    Posts
    39,927
    Thanks (Received)
    63
    Likes (Received)
    166
    Dislikes (Received)
    5
    by looking at the balancer? whats it doing? a bad balancer will knock around and could make the car run poorly.

    take the belts off see if the balancer moves by hand most of the time you can see it cracked around the outer edge.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
    Reply With Quote  
     

Similar Threads

  1. Starts, runs fine for a week, then won't start for 5 minutes, then starts and runs...
    By Summit670 in forum 3.8L V6 Naturally Aspirated (L36)(L26)
    Replies: 7
    Last Post: 04-26-2012, 05:33 PM
  2. My car starts up, runs, then dies. Please help
    By Onos in forum General Tech Discussion
    Replies: 19
    Last Post: 03-13-2012, 11:18 PM
  3. Car starts runs for 3 sec and dies
    By rtwilliamson in forum General Tech Discussion
    Replies: 11
    Last Post: 06-21-2010, 01:37 AM
  4. 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
  5. car starts, runs for a second, then dies
    By 2000GTP in forum 3.8L V6 Supercharged (L67)(L32)
    Replies: 9
    Last Post: 03-22-2009, 11:34 AM
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
  •