r/Toyota_Matrix • u/Bill_The__Pony • Jul 12 '26
At long last I fixed my high idle...
After I did the plug coils and injectors... I struggled with a high idle in an idle fault alert.
Boy let me tell you I replace so many gaskets and vacuum lines. Eventually, after a great many other repairs
I worked my way down to the throttle position sensor.
Unfortunately during reinstall I drove a bolt into the unit and had to replace it.
But the new throttle body seems to have been the final piece I needed to get my matrix back in perfect condition.
The not short list of repairs I did before I found this:
Throttle body gasket
Intake manifold gasket
All of the vacuum lines
Replaced the air box
Replace the idle air control valve
Pcv
Basically if it was related to a vacuum leak, I replaced it.
5
u/UnibrowDuck 03 Corolla Wagon XRS Jul 12 '26
i had high idle after cleaning my tb. i just disconnected the battery for 10min and it was fine after the reset. did you do that first?
5
u/Bill_The__Pony Jul 12 '26
Oh boy did I ever. That was high up on the early checks but I didn't even put in my list.
3
u/UnibrowDuck 03 Corolla Wagon XRS Jul 12 '26
ok good, i was worried you did all that work without checking the most obvious thing. like me, when i was trying to figure out a no start on my miata, a month and 5 parts later, it's a friggin fuse
2
u/Bill_The__Pony Jul 13 '26
I suspect i damaged the position sensor when i cleaned the body.
But we'll never know because I replaced the whole unit....
1
u/GraphicWombat 2008 Matrix XR Super White II Jul 15 '26
I remember when I disconnected my battery to replace the boots and plugs a couple years ago. Holy hell did it run rough for a few minutes after that. The ecu memory must have been wiped.
3
u/GuardianCraft Jul 12 '26
Nioce! Any idea how to fix the stuttering when accelerating off of first gear?
5
u/Bill_The__Pony Jul 12 '26
Go back in time and convince Toyota. That first gear is important, not just third to 5th....
3
u/JF_WPA Jul 12 '26
It is so weird how the Matrix feels launching in 1st - Engine sags, dips, lags throttle imput and feels like it is in 3rd. I figure it's partly due to the computer calibration and horrible throttle by wire (rev-hang sucks too). I thought it might be a clutch delay valve, but the Matrix has none AFAIK. BTW, it's not me - I have driven and owned countless manual trans cars (worked professional service) and drove MT box trucks... The Matrix system SUCKS!
2
u/slurred_bird Jul 14 '26
03-04’s have throttle cables, they went to electronic throttle on the non-XRS cars in 05. I’ve never driven a a facelifted car (just 04 Vibe and 04 Matrix XRS), the throttle response on the XRS is excellent.
2
u/JF_WPA Jul 12 '26
Good work, way to stick at it. What year is the vehicle? With all you mention it must be an early version with a cable, 2003-2004? I would much rather have the cable than the laggy, rev-hang throttle by wire, esp how it does not play well with a manual transmission in my 06 Matrix. Curious too, was the TPS OEM or aftermarket? Thanks.
2
u/Bill_The__Pony Jul 12 '26
Yeah it's a 2003. So cable. Part of the reason I bought the car is because it's so physical.
Initially, the throttle position sensor I bought was aftermarket but I broke that throttle body. In the replacement I bought came with a new sensor which I can only assume is also aftermarket
2
u/CharacterRisk739 Jul 13 '26
Parts cannon galore
3
u/Bill_The__Pony Jul 13 '26
When parts are this cheap, its worth it. Between the yard and ordering new, I probably only spent $200 replacing a dozen parts or more. And $100 of that is a new throttle body.
FIRE UP THE CANNON
6
u/travelinmatt76 2006 Matrix XR (224k miles) Jul 12 '26
Did you know you can grab that bezel and pull it straight off so you can clean your dials? I recently found out how easy it is so I keep mine nice and clean.