apalmer1

i broke my exhaust off right after the Y-pipe last night on my 5VZ (3.4L) tacoma. as it is the exhaust is lined up but obviously still flooding both o2 sensors with air causing the motor to use far too much fuel and providing almost no backpressure.

my friend who has all the welders isnt going to make it back into town untill after i leave. i need to drive to portland (200mi each way) over a pass.

anybody have any instant oppinions on weather or not im going to burn a valve doing this?

nix4x4

Most likely just get poor fuel economy, but I'm not familiar with the multiple O2 sensor setup

97ltd4x4

It will run like crap,but the only thing you migth hurt is your cat....Burn a valve nope....The other thing you could possibly disconnect the before cat O2 sensor and put it in fail safe mode"check engine".the computer would try to calculate fuel trim from a set fuel map.It might not run very well though,but it may be better than the O2 sensor pegged lean condition,dumping fuel.

mt_goat

You can buy some things at the auto parts stores to temporarily patch it up, might help some. Got any pics of it?

apalmer1

it made it alright to portland and back, i know all about the effects of not having O2s on an OBDII vehicle but i think its safe to say running it that hard over the pass did burn up at least one exhaust valve. the reason i say this is that when its at idle while moving the tac bounces a couple hundred RPM. hard to tell if this is just the PCM changing fuel trim because of air blowing straight at the O2 or a burnt valve. but as of today it is missing and will no longer idle at a stop without stalling so im pretty sure i toasted one. im going to fix the exhaust later today or tommorrow and see how it does afterwards. if its still crappy ill pull off the heads and show you guys whats up.