Hi All,

93 stock with the exception of AST and Radiator.

Car was working fine until I removed the pre-cat and installed a downpipe.

Now the car starts fine, idles fine, sounds normal when revving in neutral. When driving the car runs fine as long as I'm in vacuum, as soon as it transitions to boost the car feels like it's stalling.

I figured either a nut was loose on the downpipe or the O2 sensor was toast. I can't tell if there is an exhaust leak and the o2 sensor looks fine (wire is still intact)

I re-used the stock gaskets and I thought it might be an exhaust leak but I can't locate a leak anywhere.

Anyone have any ideas for troubleshooting?

 

You would hear an exhaust leak for sure, sounds like a boost leak. Did you remove any I/C pipes or couplers for your downpipe install? Definitely a boost leak IMO.

 

Sure you don't have a giant boost leak?

-David Guy

 

Sounds like a vacuum line has come off. Check vacuum lines, and Map sensor line.

 

Just to close the loop... Turns out it wasn't the downpipe install or a boost issue. Just bad timing for a stuck open secondary fuel injector. So what I was feeling was the car running wayyy too rich. Should have checked the codes way earlier :/