Major problem with new O2 dump! Any info on...

[mccurdy]

Ok...I JUST put a new 2.5 inch o2 sensor housing with a dump tube in tonight. I disconnected the o2 sensor from its plug, unbolted the coolant hard line, drained the coolant. Disconnected the o2 stock housing. Rebolted the new o2 dump housing. Reconnected the o2 sensor in the new o2 housing. Reconnected the coolant line, refed coolant into the car. I took off the bottom heat shield, but left the top mani heat shield on.

I ran the car for like 10 minutes, and it ran incredable. It sounded mean as hell, and flowed great! Then i tried launching it and max psi (about 21 lbs of boost) on my profec-b with the balance set at maximum. I hit about the middle of 2nd at full boost and BAM. car buckles HARDCORE. i slow way down, and try to accelerate again. It goes from -24 vacuum to 0 psi perfectly normal, almost instantly like it should. But from 0 to 5 i noticed it was slower. then anything after 5 psi, the car starts Hesitating big time, and actually starts slowing down the higher the PSI i go! It also makes a really wierd noise.

I have no white/black smoke i can tell from the tailpipe. Im still using the origional o2 sensor, i have no check engine lights, no visual signs of any leaks anywhere.

I CANNOT FIGURE IT OUT!!! What would make the car hesitate and slow down under boost, yet it goes from vacuum to 0 psi perfectly normal! I can drive it fine under boost and get it up to 90 MPH and drive it on the freeway just fine, yet if i try to mash on it, it just bucks/hesitates and slows WAY down!

Please help guys, i have till monday to figure out this problem!

 

[ItsStockOfficer]

Sounds like you may have blown the vacuum line off the fuel pressure regulator on the driver side of the fuel rail. Or you have a boost leak....

 

[CR95GST]

I've got $10 on the FPR vacuum line. If thats what it is, spray a little hairspray on the FPR barb and then put the vacuum hose back on. It won't blow off again.

 

[ItsStockOfficer]

I ain't taking that bet =)

 

[1fast97gsx]

yea check all vacuum lines

 

[mccurdy]

ive checked all vacuum lines. I dont know which one goes to the FPR, but on the drivers side of the bay, near the top of the bay, i dont see any vacuum hoses blown off. everything is attached where it should be. I cant see any visable boost leaks that would cause such a violent jerking motion like its doing now.

It jerks like mad once i start making boost, once the WG begins to open. Could the o2 sensor be throwing some mixed readings and cause the car to jerk like it is? But the car ran fine with the new o2 dump on for 15 minutes! what could it be?!

god i need some weed and or beer

 

[CR95GST]

drugs, what a winner

Check to see if the O2 --> Downpipe gasket got blown out. You'll lose a lot of power if you have a big exhaust leak there. I know this from experience.

 

[DSM007]

Sounds to me like a huge boost leak.....make sure to use an air compressor not a bicycle hand pump when you check for those boost leaks....use soapy water everywhere.....ya never know it maybe just like everybody else said it could be a vac line popped off......hell I remember I used to get huge boost spikes........boost leak tester helped me find a very small split in my vac line going to my BOV,problem solved.......good luck with the car bro.

 

[dsmturboawd]

no, cause boost leaks cause messed up idles. he said originally that he idled/ran the car for 10 min perfectly.

you need to test your vaccum lines, see whats going on.

 

[ItsStockOfficer]

unless you just have a bad clamp that seals until it gets pressureized.

 

[dsmturboawd]

true.

i say leak test i guess. leak tester costs all of 3 dollars to make.

 

[2-0turbo]

You blew an intercooler hose. Check them all. I guarantee this is the problem.

 

[GS><]

it DEFINATLY aint an intercooler pipe he wouldnt be getting to 90 with an intercooler pipe blown off. Is the car running fine everytime that you drive it for the first 10 min cold or does it screw up all the time now? if the really weird noise sounds like a kazoo then it is prolly the turbo giving up, does the engine idle faster now, i have had vaccum leaks that still made my boost gauge read right but only cause the engine sped up cause of the extra air and was still causing vaccum just at a different engine speed. It really sounds like you got a fpr vaccum leak, or just another vaccum leak. The fpr is the thing that is on the drivers side of the fuel rail, it has a vaccum hose on one post and a fuel return line on the other and it is bolted to the fuel rail. well i hope that i was of help see ya

John

 

[1fast97gsx]

blown off intercooler hose and the car won't run....

could be a blown gasket between the O2 and downpipe, but most likely a vacuum line. Make your own boost leak tester and try it out.

 

[flinguist]

I had a similar problem, and everyone kept telling me it was a boost leak. Turned out to be my plugs. Check your plugs, wires, and coil packs. Good luck