93 PGT: Bucks sometimes during hard acceleration

I own a 93 PGT. the check engine light was on for a while and a few weeks ago the car started bucking (sudden drop in rpm) during hard acceleration (not always, but about once a day). Took it to the shop and got error codes for VRIS solenoids, which i got fixed, but it didn't solve the problem. it also needs one o2 sensor replacement.
Any ideas on what might be causing it to buck like that?? it even does it sometimes at normal operating temperature!!
Thanks in advance for your time and help!!

Check your throttle body to VAF sensor intake elbow. Sometimes cracks can develop here causing strange idle and driveability problems.

Also, try adjusting your TPS:

Try adjusting your throttle position sensor (TPS). You can do this by following the directions in the link provided. Also, the directions don't specify, but the fans should be off in diagnostic mode. So set the TPS at the point where the fans just turn off.

Link to Rick's TPS adjustment page: http://www.rs-productions.com/RSP_Motors/tech/tps/tps.htm

Find the diagnostics box:
http://home.comcast.net/~mmunoz70/z/diagbox.jpg
Use a small paperclip to jump the TEN and GND (pic follows):
http://home.comcast.net/~mmunoz70/z/paperclip.jpg
Jumped diag box:
http://home.comcast.net/~mmunoz70/z/pinout.jpg
Then rotate the TPS (keep the screws slightly “draggy” to hold the TPS):
http://home.comcast.net/~mmunoz70/z/tps01.jpg

are you trying to sell it or are you looking for parts for it or what?? if your trying to seel it, for how much?? if you need parts weve got them. just contact me. thank you.

jessi :biggrin:

btw, if you haven't done a tune-up in a long time, you should do one.

-plugs, cap, rotor, ignition wires, fuel filter, air filter replacement or cleaning, a bottle of fuel injector cleaner