85T Bad Hesitation/Hiccup/Misfire

I've tried to do that and using my dads o2 socket set to pull it out but after the 2nd slip I didn't want to risk it. Took it to a muffler shop but they couldnt break it loose without slipping either and they couldn't install the bung in a the same area.

Currently I'm driving without the o2 sensor, but startups it tends to backfire, when getting into boost (at 1 psi and above) it hesitates, at wot feels like it doesnt want to accelerate, and runs lean which confuses me as i thought some said it would run richer.

I'm sure you guys may know exactlt what it could be, I'mjust tired right now from clinicals.

Isn't the o2 in just the down pipe after the turbo? Can you find a used down pipe?

The bung is different sized too isn't it? Get a used down pipe like JFM said, but with the right sized bung and maybe the correct o2 sensor already in it

I may try that, but taking it off might be somewhat of a problem as I don't want to snap any bolts and what not, but I was going to park it when winter hits and get a turbo back exhaust to replace the stock system, but I may see about removing the downpipe whenever i get a good amount of free time from school for that O2 sensor.

This may prove useful:

http://redz31.suomiz.net/pages/turboupgrade.html

• 88-89 turbo cars that have the T25 DO NOT use the same exhaust elbow, the exhaust turbine housing is slightly different, and contains the wastegate flapper as part of the turbine housing as opposed to part of the elbow.
• If you have a T25 (88-89 300zx turbo) you will need to find a Nissan T3 exhaust housing and O2 elbow off the earlier Z31 turbo cars.
• 280 ZX Turbo's (S130) use the same T3 as the 300ZX turbo (Z31) did in 84; the turbo is the same, but the exhaust elbow is not.

OK stupid question but are you *absolutely sure* that the ECU you borrowed is for a turbo? Like, did you check the serial? That sounds a little bit like the NA tune on a turbo. I remember somebody else had this problem ages ago. Might be a totally dumb question, but easy to check.

Yeah, I checked it before putting it in to make sure, don't remember the serial number off the top but it said from 96 turbo 5speed federal.

Thamks, i appreciate you looking into it for me, ill see about finding the elbow for it online or fromnsomeone else depending which comes first.

nvm

Alright so update: it's still lean, I did find 2 vacuum leaks for the breather houses. Replaced them and she perked up a little, but still lean. I am confused as to where else to check as I've tried ditating brake cleaner at anywhere thay air could get in but haven't found one (yet) wondering what input you guys may have to help me out.

Saw this on FB. Not sure if you were looking for one. https://www.facebook.com/groups/9327…55332868872867

You ever figure this out?

haven't been on here as much as school has been royally throttling me. I did, it was the Fuel pressure regulator wish I couod have confirmed way sooner but at least it was fixed.