fuel cutting out or bad timing what?
03-14-2008, 01:12 PM
#1
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fuel cutting out or bad timing what? ok, quick overview before we get to the problem. I have a '99 t/a and had my engine stroked & rebuilt while i was out to sea for 6 months (navy submarine). I had to give the mechanic an artisic license and a budget cuz i wasnt going to be there to give the go/no go on stuff. that being said, i don't know everything he did cuz he doesnt remember everything he did. heres what I know: stroked(383), ls6 intake manifold, fast90 intake, some kinda cam, 243 heads port polished, long tube headers, dyno tuned, and some other stuff. He got the car running and returned it to me (after i paid him 11,000$), but now he's "too busy" to finish what he started and work the kinks out so i'm trying to.
now that i got that out of the way, here's the problem: the car sometimes goes into a low-idle-funk at stoplights where it sticks at 500rpm for a bit, then jumps up to 1200 rpm, then settles to 900. if i try take off while it is stuck at 500, the car has no power (rpms increase when excellerator is pressed, but no power to show for it). It feels and sounds as though it is only running on 2 or 4 cylinders. this "gross power loss" phenomenon also sometimes happens while im driving down the road. I will be getting onto the highway in 3rd gear at 2500 or 3000 rpm and then my power falls through the floor. the weird part: when i turn the ignition off and back on real fast, it snaps out of it's funk and remebers that it is a v8 beast, laying rubber in the middle of the intersection. People behind me wonder why i creep through the intersection at like 2mph, then take off like a scalded dog.
i just read the codes and i got a couple of o2 sensor codes, and a knock sensor code. i knew about the o2 sensors, cuz my sensors are too far down stream due to long tube headers, but the knock sensor is new. ive never heard any spark knock from it, so i dont know why it would retard my timing. The problem seems too intense (to me) to be due to a knock sensor. and why would cycling the ignition fix the knock sensor anyways? or any sensor for that matter? maybe i'm wrong. i really don't know a whole lot about how these electrical things work. please help
oh yeah, and sometimes, instead of sticking a 500 rpm, it sticks at like 2000-3000 rpm until i tap the gas pedal, at which point it goes into it's 500 rpm funk. thanks.
now that i got that out of the way, here's the problem: the car sometimes goes into a low-idle-funk at stoplights where it sticks at 500rpm for a bit, then jumps up to 1200 rpm, then settles to 900. if i try take off while it is stuck at 500, the car has no power (rpms increase when excellerator is pressed, but no power to show for it). It feels and sounds as though it is only running on 2 or 4 cylinders. this "gross power loss" phenomenon also sometimes happens while im driving down the road. I will be getting onto the highway in 3rd gear at 2500 or 3000 rpm and then my power falls through the floor. the weird part: when i turn the ignition off and back on real fast, it snaps out of it's funk and remebers that it is a v8 beast, laying rubber in the middle of the intersection. People behind me wonder why i creep through the intersection at like 2mph, then take off like a scalded dog.
i just read the codes and i got a couple of o2 sensor codes, and a knock sensor code. i knew about the o2 sensors, cuz my sensors are too far down stream due to long tube headers, but the knock sensor is new. ive never heard any spark knock from it, so i dont know why it would retard my timing. The problem seems too intense (to me) to be due to a knock sensor. and why would cycling the ignition fix the knock sensor anyways? or any sensor for that matter? maybe i'm wrong. i really don't know a whole lot about how these electrical things work. please help
oh yeah, and sometimes, instead of sticking a 500 rpm, it sticks at like 2000-3000 rpm until i tap the gas pedal, at which point it goes into it's 500 rpm funk. thanks.
03-14-2008, 05:47 PM
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thanks, i called another shop regarding getting it tuned, and they said some stuff i didnt really understand about my first mechanic having the license for the tune and they would have to get a new license and it would probably cost over 600$. sounded like a bunch of b.s. but i don't know. i would hate to pay 600$ for someone to hook up a laptop to my car because iv'e seen how "difficult" it is to do, and that seems like a rip off. I'm also not that confident that i could do the tune if i had the software cuz i'm not too edumacated on that stuff. i'm afraid i would do more damage than good.
03-14-2008, 05:54 PM
#4
it actually sounds like a vacuum leak to me. also, if your knock sensors are goin off that's a simple fix you can do in your driveway, both just sit under the manifold and chances are he accidentally pulled them loose cause he sounds like a douchebag anyway lol and then there's the other thing . . . . A VERY SHITTY TUNE lol wouldn't reccommend goin back to that guy btw changing your fuel filter isn't a bad idea anyway
03-14-2008, 10:59 PM
#5
Too bad the guy that did the work can't finish it up. And he can't even tell you what's in there for a cam? Jeez.
Check all the usual stuff. Make sure the MAF is clean. Make sure all the plug wires are on there good. Check electrical connectors and sensor fuses. Make sure the grounds are secured, especially the ones on the back of the DS head. (If those aren't on there, the car will run really screwy. How do I know? heh
)
What's your location? Maybe someone will know a good shop in your area.
Check all the usual stuff. Make sure the MAF is clean. Make sure all the plug wires are on there good. Check electrical connectors and sensor fuses. Make sure the grounds are secured, especially the ones on the back of the DS head. (If those aren't on there, the car will run really screwy. How do I know? heh
)What's your location? Maybe someone will know a good shop in your area.
03-14-2008, 10:59 PM
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it actually sounds like a vacuum leak to me. also, if your knock sensors are goin off that's a simple fix you can do in your driveway, both just sit under the manifold and chances are he accidentally pulled them loose cause he sounds like a douchebag anyway lol and then there's the other thing . . . . A VERY SHITTY TUNE lol wouldn't reccommend goin back to that guy btw changing your fuel filter isn't a bad idea anyway
Last edited by tuna10985; 03-15-2008 at 01:22 AM.
03-15-2008, 01:21 AM
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Too bad the guy that did the work can't finish it up. And he can't even tell you what's in there for a cam? Jeez.
Check all the usual stuff. Make sure the MAF is clean. Make sure all the plug wires are on there good. Check electrical connectors and sensor fuses. Make sure the grounds are secured, especially the ones on the back of the DS head. (If those aren't on there, the car will run really screwy. How do I know? heh)
What's your location? Maybe someone will know a good shop in your area.
Check all the usual stuff. Make sure the MAF is clean. Make sure all the plug wires are on there good. Check electrical connectors and sensor fuses. Make sure the grounds are secured, especially the ones on the back of the DS head. (If those aren't on there, the car will run really screwy. How do I know? heh
)What's your location? Maybe someone will know a good shop in your area.
there's no MAF. I guess he bypassed it or something, but i've got my air filter mounted right onto my intake. i will check the grounds and fuses. I'm in norfolk, virginia.