90 NA bogs after shifting

[Recian]

I've been chasing this problem now that the weather has cooled down. My NA will bog after shifting and accelerating. It's only if you try to get on it more than say 40% throttle. It makes the car feel very slow since you accelerate, shift then lose all power almost til about 3200+ RPMs. First gear on take off doesnt do it. Just 2, 3, 4.
The conscern is worse when the vehicle is cold. It seems to go away when at operating temp however it's not completely gone just a bit better.
I've put new plugs and fuel pump along with timing belt. There's no CEL light on.
I have yet to do a plenum pull to replace all vacuum hoses but the car was garage kept with 83k miles and the hoses visually look ok. It does seem to have a bit rough idle whenever it drops below 800 RPM but not extremely bad. Turning the auto climate on to kick on the compressor and jump idle to 800 will remedy this. I wouldnt think this small of a vacuum leak (what i think it is) would cause my stumble problem.
I've read alot of guides to issues like this but nobody seems to have the same information or lead me in the right direction. Any advice would be appreciated.

[z32loverboy]

My guess is that it's either a vacuum leak, PTU problem or a coolant temp sensor. That's my guess anyway without touching the car myself.

[Recian]

Is there any way to test the PTU? looks like it has control of the VVT. That would definitely cause a problem. I think the car has a small vacuum leak but I wouldn't think a small one would cause an issue that large.

[Recian]

there's a guy here with a 91 NA he's had since it was new practically. He has me do a lot of work to it. I was talking to him last night and he said his had the same problem a few years back and he replaced the fuel pressure regulators.

[solaire]

Kinda reviving this to see what other replies i can get. The problem is getting worse. Today it did it really bad almost like the car had no throttle response after shifting for a couple seconds. It normally feels like turbo lag (this is a NA car) but today it was really bad like can't get out of traffic's way bad. I'm wondering if I should watch fuel pressure and see if it drops out during the problem or would removing vacuum to it do the same thing as keeping it closed all the time? See if it makes any change. Unfortunately I have no PTU or MAF to slap in to check. (It does seem worse under more load / throttle) Connections are fine. I cleaned the typical one at the PTU to be safe while I had it apart checking. I would think if CTS or O2s were giving issues enough to cause a drivability problem I would have poor MPG but I get 25 hwy and around 18-20 in town.

[solaire]

Made progress today. Went to check DTCs and noticed the CEl didnt come on.. further checks the bulb was blown. Changed that and now I have a code 53. Wonder if the O2 sensors could cause this problem and what would be an acceptable brand to change them with.