Bogging down at 16psi (Im a newbie)

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Thats how I've got it hooked up, good there! I thought I had it wrong and thats what was causing it to build boost too fast. After the exhaust leak fix I did notice its back to surging while at idle and the BOV is much louder, Im going to check out the codes here shortly and see what it says and rule that out.

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Well guys Im changing out all my vacuum lines tomorrow and ruling out that first. My DTC code was just a IAC failure, so I bought a new one. All I know of next is to check fuel pressure. How much more fuel pressure should I pick up under boost? 1lb for every PSI? My air/fuel gauge is showing lean under boost so I think is all in fuel pressure.

 

[Flyin Ryan]

Re: Bogging down at 16psi (Im a newbie)

My DTC code was just a IAC failure, so I bought a new one. All I know of next is to check fuel pressure. How much more fuel pressure should I pick up under boost? 1lb for every PSI? My air/fuel gauge is showing lean under boost so I think is all in fuel pressure.

Is this error showing up alot? You could pull the ECM B fuse for a few minutes to reset the computer and let the computer relearn the truck to see if the error returns or if it's just an old error that was stored and is no longer a problem.

Yes 1lb per psi of boost is correct.. and I believe stock fuel pressure with stock chip/turbo etc is 43 with the vacuum line unhooked and plugged but don't qoute me on that it's been a while since i've delt with that.

 

[SBNova]

Re: Bogging down at 16psi (Im a newbie)

My bet is on ignition....

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

No the error isn't showing up anymore because it was a IAC and I fixed it yesterday. I also went ahead and reset the computer and let itself relearn. The truck has a pitbull chip and pte44 turbo and was always ran at 16psi, so what do you think the pressure should be at 45? I dont think is the ingition because Ive had 3 sets of plugs in it and changed just about everything, but you never know. Im going to check pressure first along with replacing vacuum lines.

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Now I wonder if maybe its timing? Ive only had the truck a week and its a pain, but I'll get it figured out!!

 

[Gnocide]

Re: Bogging down at 16psi (Im a newbie)

Wow is that true? My motor mount is BUSTED. I cant launch from more than - 5lbs boost. Even coming near 0 its REALLY hittin the hose. And I cant build more than 4-5 lbs while driving normally. That would explain it. No one offered up that solution to the problem before. Time to order some motor mounts!

mine would go fine untill more than 75% throttle then fall on its face

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Gnocide, was your problem all because of a broken motor mount?

 

[Gnocide]

Re: Bogging down at 16psi (Im a newbie)

Gnocide, was your problem all because of a broken motor mount?

yes -
truck was fine untill fast or sudden heavy throttle then around 14 psi(mine goes to 18}
it would slow down strain and even pop becuase the motor was moving so that the knock sensor was going crazy and the cpu was pullling timing out

if i eased up on the throttle it would settle down and pick back up again untill boost climbed

have someone put it in drive and power brake it with the hood up and look at the amount of movement from the left side of the engine to be sure
-

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Well I got all the vacuum lines changed and checked the fuel pressure.

Right now at Idle Im at 48lbs. I did happen to notice the there was some

signs of the alt. hitting the insulation on the hood, so could be mounts.

Im not for sure seeing as the engine is newer, but could have broke since then.

Ill have someone put it gear and check it out. Now that the Vacuum likes are changed

the gauge shows lean under heavier throttle. I didn't get a chance to check fuel pressure

while driving it because I just have a tester not a guage in the truck. When I checked

pressure I plugged both vacuum line and regulator, is that right?

 

[Gnocide]

Re: Bogging down at 16psi (Im a newbie)

I did happen to notice the there was some

signs of the alt. hitting the insulation on the hood, so could be mounts.

Im not for sure seeing as the engine is newer, but could have broke since then.

Ill have someone put it gear and check it out. /QUOTE]
could be- mine looked okay and came out in 2 pieces

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

I'll go ahead and swap them here before too long if they move alot.

I know that a air/fuel gauge isnt the most accurate way to see mixture, but

It seems to me that its all over the place when in boost. It could be lean at 10psi one

time and rich another, but when it hits 16psi its always lean and cuts out. How often

does anyone have Knock sensor failure? Just wondering if they are a problem. Id like

to get a logging software for the truck, but I just bought LS1edit pro for my trans am and

I'm already down $1200 for it. I may try to find someone in my area who has software and

see if they could help get the problem narrowed down if its not the mounts. Thanks for

your help!!!

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Ok guys, checked the motor mounts and I good on that, motor doesnt move much. I'm still going to make a torque strap so I dont tear one. I just got done driving it one more time and still missing at 15-16psi. I really think its cutting timing, knock or comp. (I know need datamaster) It does have a pitbull chip, so how much boost would the chip allow before cutting back on timing? Im also starting to wonder if its just that Its very cold out right now(18degrees) and when I bought it, it was like 50 out and seemed ok on boost. Do these trucks get affected by temp easily? I have a 02 supercharged GTP with a smaller pully and It does run lean in the winters because the cold air is more dense. I dont know if Ty's are like that because of heat from the turbo. Thanks again!!!!

 

[makws6]

Re: Bogging down at 16psi (Im a newbie)

Well problem solved, thank god!! I went ahead a bought a set of autolite 23's(works damn good in my GTP) and pulled the MSD coil for a stock one I had laying around. Gapped the plugs at .032 and ran good all the way to 16psi!!! I guess I just didnt have luck with ur5's on this truck or just got bad one. Thanks for all the suggestions!!!