help with matirx tb....oscillating rpm???

[xxae07xx]

just installed 05-07 matrix tb. rpms oscillate at idle. does it just take time for ecu to recalibrate? anyone else come across this problem? solution?

[ROCKLAND TOYOTA]

any CEL light yet???//

[xxae07xx]

nope. problem solved tho

[ztrack157]

What was the problem? Or still don't know.

[YarisSedan]

I think he solved the problem by putting the original one back on =)

[slvryaris]

Probably a wiring issue.

[YarisPR]

Originally Posted by ROCKLAND TOYOTA

any CEL light yet???//

I have the same problem...... Cold strt it revs up to 3000rpm then it idles between 1000rpm sometime a bit over 500rpm. But when I push the engine hard and then put the car on neutral it oscillates a few seconds and then back to normal

[FunctionSpec]

Air bubbles in the coolant lines.

To the people who want to do this mod in the future:
Bleed out air bubbles in coolant lines after install. Your RPMs will jump up and down at idle if you don't bleed out the air bubbles. Since air and coolant heat up at different rates, theres a big difference in temperature which causes the Temperature Sensor to sense different temps whenever the air bubbles travel over the sensor causing the RPMs to oscillate.

[mikenacarato]

i tried installing the corolla tb on my car tonight and i bypassed the coolant alltogether going into the throttle body. my rpms are jumping from 1000-4000 like a bad idle air control valve would do. do i have to reconnect the coolant lines going into the tb?

just to make sure, everyone is installing these without doing any modifications right?

[ztrack157]

Yup I'm doing mine next week. To bleed the air don't we just open the radiator cap and wait until we see no more bubbles rising.

[FunctionSpec]

Originally Posted by mikenacarato

i tried installing the corolla tb on my car tonight and i bypassed the coolant alltogether going into the throttle body. my rpms are jumping from 1000-4000 like a bad idle air control valve would do. do i have to reconnect the coolant lines going into the tb?

just to make sure, everyone is installing these without doing any modifications right?

I would connect the coolant lines going into the TB to see if there isn't a problem with the TB itself. Properly bleed out the air in the coolant and check to make sure there isn't a problem with the TB.

There is only a slight modification to the install. You have to readjust the metal coolant tubes to position them like the stock Yaris TB. If you don't, the coolant hoses will be too short and won't reach the tubes. Take a rag and a wrench and slowly readjust the tubes. The metal tubes are press-fitted in and will move. Just be careful not to scratch up the tubes or bend them.

Originally Posted by ztrack157

Yup I'm doing mine next week. To bleed the air don't we just open the radiator cap and wait until we see no more bubbles rising.

Yups, make sure car is cool before opening up radiator cap. Open up radiator cap, turn on car, and let it warm up. Carefully squeeze the small hoses running into the TB and be careful not to burn yourself. Don't squeeze too hard or you'll have a coolant mess. Let it run some more and just watch the coolant until you see no more bubbles coming out when you squeeze the hoses.

[mikenacarato]

why would the lines going into the tb have anything to do with rpms jumping, other than the bubbles part. ive had the coolant bypassed from my stock tb for at least a week with no rpm jumping, and i did not open any coolant lines when i swapped out the corolla tb.

[FunctionSpec]

Just to test and check cause it sounds like you might have a defective TB.

Also check for any air leaks with the intake piping.

How did you connect the stock yaris intake tube to the corolla TB?

[mikenacarato]

a little grease and some muscle. it didnt sound like air was being sucked in anywhere unusual though.

[YarisPR]

I think I have a faulty TB or a Bad intake conection since I have the TB bypass for like 5 3 months (and no problems) and I haven't touch the lines or the coolant deposit. I'll work on it next year....LOL

[mikenacarato]

me too, where did you get yours from?

[richardholdener]

Not sure if the matrix TB is anything like the XD tb we ran during testing, but if it is as large as the Xd tb, then you likely have a sealing problem between the o-ring on the throttle body and the throttle opening on the intake manifold.

[mikenacarato]

thats another thing i was thinking. the stock size o ring fits into that groove and could possibly leave a gap between the manifold and tb. ill install it when i get your manifold richard and see what happens.