Vacuum leak? Map problem? Help!
08-30-2015, 07:54 PM
#1
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Vacuum leak? Map problem? Help! Ok so i still havent been able to get a scanner to where the car is stuck to see if it popped any new dtc's, but this is what it had prior to this problem.
P0107 (can't even erase it)
P0135
P0530 (I dont even have a/c? Shouldnt this code have been removed?)
Before the tune, i only had the usual codes associated with a big cam.
Setup is
Lq4 block
Prc 2.5 5.3 heads
Comp lsr624 cam
Fast 102/102
After the tune the only issue ive had is a rolling high idle. Once at running temp, It wanted to hang between 2&3k rpm till i was at a complete stop for about 3 seconds then it would settle.
The other night, pulling out from a stop it backfired, bogged then took off. Then i had to ride my brakes down a windy hill as it tried to accelerate on its own as much as it could. So i pulled over and it was idling very low and smelled horribly rich(watch vid). I pull out again, and now its bogging and backfiring at 30% throttle or less, but takes off like a rocket 30% to wot. I immediately think iac or tps so i change tps and test iac which seemed fine. No change.
Next day i notice how oiled up it is at the back of my manifold. I reached back, and could feel my brake booster hose, but couldnt find anything else. Im not sure if my arm is too big, or if my map sensor/hvac vac bung is missing. I took it for another drive and it now doesnt wanna move no matter what the throttle position is.
Is it possible that entire bung shot out of the manifold? Would that hvac line not being connected cause that a\c code? It would certainly explain the map code in my head. My big question is how was it not running like this the passed 6 months if that were the problem?
Im hoping i can get some good insight before i start rippin the intake back out.
Please help!
https://youtu.be/H7GGD0IMVsU
P0107 (can't even erase it)
P0135
P0530 (I dont even have a/c? Shouldnt this code have been removed?)
Before the tune, i only had the usual codes associated with a big cam.
Setup is
Lq4 block
Prc 2.5 5.3 heads
Comp lsr624 cam
Fast 102/102
After the tune the only issue ive had is a rolling high idle. Once at running temp, It wanted to hang between 2&3k rpm till i was at a complete stop for about 3 seconds then it would settle.
The other night, pulling out from a stop it backfired, bogged then took off. Then i had to ride my brakes down a windy hill as it tried to accelerate on its own as much as it could. So i pulled over and it was idling very low and smelled horribly rich(watch vid). I pull out again, and now its bogging and backfiring at 30% throttle or less, but takes off like a rocket 30% to wot. I immediately think iac or tps so i change tps and test iac which seemed fine. No change.
Next day i notice how oiled up it is at the back of my manifold. I reached back, and could feel my brake booster hose, but couldnt find anything else. Im not sure if my arm is too big, or if my map sensor/hvac vac bung is missing. I took it for another drive and it now doesnt wanna move no matter what the throttle position is.
Is it possible that entire bung shot out of the manifold? Would that hvac line not being connected cause that a\c code? It would certainly explain the map code in my head. My big question is how was it not running like this the passed 6 months if that were the problem?
Im hoping i can get some good insight before i start rippin the intake back out.
Please help!
https://youtu.be/H7GGD0IMVsU
08-30-2015, 08:19 PM
#2
I feel like you'd hear a major leak if the map sensor blew out. Spray some brake/carb cleaner around the intake while the at I idling. If you have a leak the engine will rev up
01-25-2016, 01:15 PM
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Ok. So I pulled the intake, and I WAS missing my map. I also decided to swap to ls6 pcv while I had it apart.
So, it has new
Ls6 pcv setup
Tps
Iac
Map
Maf (with screen)
It was immediately running better, but it's still doing the bogging/miss firing **** from idle to as high as 2800rpm no matter what the throttle position. Sometimes when I go to pull out, it'll pretty much sound like it shut completely off for as much as 3-4 seconds with my foot to the floor, then it backfires a few times, bogs, then takes off like nothing was wrong.
Now the idle problem, it'll idle perfectly fine one moment, it'll idle around 2k another moment, and it'll hunt from 450ish-2400ish rpm the next. Sometimes when it starts surging, if it stalls, after startup it won't even stay running unless I bump the throttle stop a little.
I'm having maf codes, Tps codes, o2 codes, and for some reason a traction control code out of nowhere
So, it has new
Ls6 pcv setup
Tps
Iac
Map
Maf (with screen)
It was immediately running better, but it's still doing the bogging/miss firing **** from idle to as high as 2800rpm no matter what the throttle position. Sometimes when I go to pull out, it'll pretty much sound like it shut completely off for as much as 3-4 seconds with my foot to the floor, then it backfires a few times, bogs, then takes off like nothing was wrong.
Now the idle problem, it'll idle perfectly fine one moment, it'll idle around 2k another moment, and it'll hunt from 450ish-2400ish rpm the next. Sometimes when it starts surging, if it stalls, after startup it won't even stay running unless I bump the throttle stop a little.
I'm having maf codes, Tps codes, o2 codes, and for some reason a traction control code out of nowhere