Soooo... Update!!! A week ago I took off and throughly cleaned throttle body and IAC valve, replaced mounting gaskets for both and that seems to have taken care of misfires. Had a couple of "pending" misfires show up on scan tool since but they cleared themselves quickly without ever throw...

Also, CEL has never flashed , just comes on and stays on. Car drives around and accelerates just fine . Just notice a slight miss sitting at lights but never feels like it's gonna die. And just one small slight hesitation on initial acceleration sometimes.

Waiting on delivery of obd scan tool to check out fuel trims. Have not done compression test (never done one before) but I know I can rent a tester and to do it soon.

Already replaced intake manifold gasket with newer orange one from Toyota dealer.

From what I understand P0420 is not neccesarily just a bad cat that needs replaced. The P0420 could just be getting thrown by excessive gas from misfires. I've ran a vac gauge test that does not indicate exhaust blockage. Again... I need to troubleshoot and pin it down rather than just throw parts a...

2003 base FWD 162k miles. I bought this vibe a month ago. Ran fine, a little underpowered and some exhaust noise. Started getting p0300 and p0301 p0302 p0303 p0304 and p0420 after couple days driving, can feel slight misfires at idle, sometimes a slight hesitation on initial acceleration Took care o...

Sorry dude. I started to post all the links but don't really have a computer to use handily so using my phone for all this and have them all bookmarked on here and trying to paste in all the links is just too much on this dinky screen. All the info is out there with just a little effort in googling....

Yep. I've no idea how long the aftermarket cat has been in there but I assume it's what is causing the code. I checked it for loose material though and it sounds solid. I also have plenty of air coming out of exhaust and emissions passed fine, so it's a future replacement when I have the time and ca...

Understood. Would enlarging the factory Intake hose from headlamp to box make a difference, like this (in the 4th post down by "blue94")
http://matrixowners.com/index.php?/topi ... +%2Bfilter

Oh ok. I updated my profile. Currently Albuquerque, NM but moving to Atlanta, GA sometime in the next few weeks.

I ran a test for this by opening the air box and temporarily taping the filter to the top of the box so as to run the test with clean air. A definite performance increase and the same growl/howl at higher revs. I put the air box back together normally but on a trip to the junkyard I picked up a spar...

I did this a couple of days ago. I removed the valve first and after removing the one bolt that holds it in, I found I had to pry quite a bit to slide the valve out from the engine block. I didn't replace it, just cleaned it. I didn't remove the alternator or Intake manifold so getting to the VVTI f...

Went for a spin out into the mountains...

Oh, and by the way, I live in an apartment. I did all this work with the left side of the car driven up onto a high kerb on the street. Fun!

So... Yesterday, due to the seeping fluid at back edge of the tranny pan after my drain/refill & filter change, I decided to redo the tranny pan Gasket. One of the bolts sheared right off as I was trying to take it off. To make things interesting it was the only pan bolt that goes into the trann...

Sure! The paint on roof and hood is bad from the New Mexico sun and I don't have the engine bay as clean as I'd like yet but I'll post up a few tomorrow.

I bought a 2003 base 2wd, A/T with 139k miles and with the help of these forums and a bunch of time on my hands, getting ready to move from NM to GA, I have completed the following maintenance items... Changed oil Cleaned Maf: Easy 5 minute job Replaced spark plugs: Easy plug job on Vibe! Replaced a...

Hi everybody. I'm the proud new owner of a 2003 base vibe! She/he (gender has yet to be revealed) has 139k miles, auto trans, red paint. It's been neglected by previous owners and is rough around the edges but everything works, no oil leaks and I picked it up for a great price. I've done a lot of wo...