BOOST going Nuts!!!

[00s4slvr]

alright so i changed my dv's to 710n's and changed my n75 to the race n75 this past weekend. The car is on STOCK mode and i took it for some runs saturday night on the way to the movies and my boost when i got on the highway held 9-10 all the way to the redline. It was about 50 degrees F that night. Tonight i just did some bs runs from like 20-60 and my boost was at like 5-6 going to 10 then to 6-7. It was all over the place. It was 25 degrees F tonight.

What is going on? does the temperature have anything to do with the boost?

[00s4slvr]

i scanned the car for codes also and nothing except that oxegyn sensor lambada internal resistance to high. but i know thats for the O2 sensor which im gonna replace soon.

any ideas guys??

[CONTROL ONE]

Are you sure you have the right program loaded? Do you have an actual stock ECU you can try to be sure?

[highPSI-S4]

i scanned the car for codes also and nothing except that oxegyn sensor lambada internal resistance to high. but i know thats for the O2 sensor which im gonna replace soon.

any ideas guys??

Depending on which o2 is bad, it will affect boost.

[Boosted-S4]

you have exactly the same problem that i have!!
on the highway my boost goes nuts and when i scanned my car i had b2 s1 o2 internal resistance too high!!
i have allready ordered new o2s and that should solve the problem!!

[highPSI-S4]

Yes it should, sensor one on both banks is the o2 closer to the manifolds which are the ones to worry about and will cause the car to act up with boost and cause misfires.

Although i bought a universal bosch o2 and i think it is flaky. So i have to spend some coin on a OEM PP version.

Report back when you get them installed.

[1997gtx]

You can boost 1 or 2 pounds less in the cold, but your 'problem' is larger than just the temp. change. Swap the O2 sensor before we move on to other things.
--Adam

[00s4slvr]

ok i will be changing the o2 sensors soon. I was doing some mroe runs today and i had the defog on and noticed the same problem. Then when i took the defog off and did some runs my boost stayed at 10 then taper a bit towards redline that back up to 10 again. did a run from 20-60mph or so.

[Jung]

running the a/c/heat will affect engine load. at idle, if climate control's off, your vac will be at -21Hg, but on it will be aroudn -18Hg... not quite sure if it affects directly your max boost like your 02s do, though.
i thought yuo needed a tune to run the n75 race valve.. or can you run it only on GIAC and not APR tunes?

[00s4slvr]

i am running stock program right now with the race n75 and it works great.

[GramCracker]

You've made like 5 threads about your boost.