Why does it do this? - Toyota Yaris Forums

268i · 08-23-2014, 01:42 AM

Hi everyone,

I've tried installing a pod filter on my Yaris (1.3l auto) this weekend but have been having some problems.

I use a spectre 8705 MAF housing,a silicone pipe reducer from 3" to fit the yaris orginal pipe and basic 3" pod from local autoparts store.

I start the car up and it idles at around 2500rpm, few seconds later the rpm's drop until under 1000rpm and the car shakes and the engine turns off. (Feels a lot like stalling a manual) Happens in about 10 seconds.

At the beginning I thought it was a faulty pod (restricting air flow) and left just the pipe on without the pod but the same thing occurred. Trying a different MAF sensor from my other toyota but the same thing happened. MAF sensor is positioned almost the same position as it was with the airbox.

Anyone had this happen before?

IllusionX · 08-23-2014, 06:34 AM

Did the check engine come on?

When I removed my air box to do some maintenance, I had similar results. But it also threw a CEL. Something about MAF and intake temperature. I cleared it and it was good to go.

malibuguy · 08-23-2014, 07:28 AM

Your maf housing is the incorrect diameter. If its any different then stock the readings are skewed.

At least on our 1.5s the maf housing is 60mm-2 3/8" Yours is probably the same. Larger will run lean...smaller will run rich

268i · 08-23-2014, 05:37 PM

Quote:

Originally Posted by IllusionX

Did the check engine come on?

When I removed my air box to do some maintenance, I had similar results. But it also threw a CEL. Something about MAF and intake temperature. I cleared it and it was good to go.

Check engine light only came on after engine died..

268i · 08-23-2014, 05:39 PM

Quote:

Originally Posted by malibuguy

Your maf housing is the incorrect diameter. If its any different then stock the readings are skewed.

At least on our 1.5s the maf housing is 60mm-2 3/8" Yours is probably the same. Larger will run lean...smaller will run rich

Oh, my MAF housing is 3"
But what I don't get is doesn't the ECU adapt to the difference in air flow etc over time.. (I have a fried also with 3" setup. )
Also, why does the engine shut off? AFAIK it should go into "Limp" mode..

268i · 08-23-2014, 05:40 PM

Also worth noting that the first time I started the car i revved it a little and it got to around4000rpm but then the revs just slowly went down to zero

why? · 08-23-2014, 05:47 PM

Did you unplug the battery to reset everything after you installed the intake?

But malibuguy is probably right. The Yaris is extremely sensitive to any changes. And MAF sensors can't deal with changes at all.

Exiwolfman · 08-23-2014, 06:14 PM

sounds like a vacuum leak , u sure u have everything connected right sensor facing the right way etc...

268i · 08-24-2014, 01:32 AM

Quote:

Originally Posted by Exiwolfman

sounds like a vacuum leak , u sure u have everything connected right sensor facing the right way etc...

Yup. Sensor is pretty much in the same area and orientation as it was before.

268i · 08-24-2014, 03:34 AM

I might try doing it again next weekend. I'll remove the battery this time and see how it goes. A friend of mine who did something similar said it ran quite rich for the first day or so..

Anyway.. Does the repeated experimenting with the setup (and causing the engine to turn itself of) pose any risks of damaging my engine?

268i · 09-06-2014, 06:40 PM

Update: Battery removed this time and it seemed to shut off quite quickly. I've learnt from someone thats done this before that when the engine shakes I should leave it for the ECU to learn airflow as a result of it changing and to give it a little bit of gas if its really going to shut off. However, It was pretty much impossible for me to give it a little bit of revs before the engine just cut off..

malibuguy · 09-06-2014, 09:01 PM

Im telling you from experience you need to change the maf housing to 2 3/8" /60mm

The stock computer does not have that kind of compensation built into it. Think about it...why the hell would the programmers waste time to create mappings for the off chance someone does incorrect modifications to the car??

malibuguy · 09-06-2014, 09:04 PM

I had a xB1...same motor...I originally fabbed an cold air intake using 2.5" piping and it ran lean and had no power. Switch to 2.25" and it ran rich...measured the maf and realized what I needed to do. So I made a 2 3/8" housing and it ran beautiful.

The ecu is expecting only to see a basic range of parameters thru that sensor. The wrong size housing only skews what it thinks it is seeing

fnkngrv · 09-06-2014, 09:27 PM

I was so glad when I ditched MAF. it has its place, but man it can be a PITA.

Bluevitz-rs · 09-06-2014, 11:08 PM

x2 on the 2-⅜" MAF housing. The ECU will not compensate for any deviances in that diameter. It has absolutely no reason to either as Toyota engineered it to work with the stock air box and know exactly how much air flows by the MAF. Increasing the size of the pipe increases volume but decreases velocity, so the ECU see less air going into the engine and gives less fuel. There is no reason to increase it's size to try and get more air into the engine unless you've done MAJOR engine work and require it because you have a massive throttle body and it's opening is now bigger than the intake piping.

fnkngrv · 09-07-2014, 12:37 AM

Quote:

Originally Posted by Bluevitz-rs

x2 on the 2-⅜" MAF housing. The ECU will not compensate for any deviances in that diameter. It has absolutely no reason to either as Toyota engineered it to work with the stock air box and know exactly how much air flows by the MAF. Increasing the size of the pipe increases volume but decreases velocity, so the ECU see less air going into the engine and gives less fuel. There is no reason to increase it's size to try and get more air into the engine unless you've done MAJOR engine work and require it because you have a massive throttle body and it's opening is now bigger than the intake piping.

very nicely put.

268i · 09-07-2014, 02:05 AM

Thanks everyone for advice. I bought the 3" housing all ready for the toyota MAF sensor and the company (spectre) only seem to make 3".. Might have to DIY with PVC Piping then..

Exiwolfman · 09-07-2014, 08:34 AM

Honestly don't get why u would have problem with size of piping cos when running a CAI on my Yaris with a 3 inch piping that shrinks down to 2.25 at throttle body it all works fine ...same as my Sri home made intake ...I say u have an issue with ur sensor .
Anyhow I see u got new piping let us know how it goes.

sent from my S4 on Mars

08-23-2014, 01:42 AM	#1
268i Drives: 06' Yaris 1.3l Join Date: Jul 2014 Location: NZ Posts: 46	Why does it do this? Hi everyone, I've tried installing a pod filter on my Yaris (1.3l auto) this weekend but have been having some problems. I use a spectre 8705 MAF housing,a silicone pipe reducer from 3" to fit the yaris orginal pipe and basic 3" pod from local autoparts store. I start the car up and it idles at around 2500rpm, few seconds later the rpm's drop until under 1000rpm and the car shakes and the engine turns off. (Feels a lot like stalling a manual) Happens in about 10 seconds. At the beginning I thought it was a faulty pod (restricting air flow) and left just the pipe on without the pod but the same thing occurred. Trying a different MAF sensor from my other toyota but the same thing happened. MAF sensor is positioned almost the same position as it was with the airbox. Anyone had this happen before?

08-23-2014, 06:34 AM	#2
IllusionX It's the illusion you see View User's Garage Drives: 07 Yaris Sedan Aero Join Date: Oct 2006 Location: Brossard, QC Posts: 3,888	Did the check engine come on? When I removed my air box to do some maintenance, I had similar results. But it also threw a CEL. Something about MAF and intake temperature. I cleared it and it was good to go. __________________

08-23-2014, 07:28 AM	#3
malibuguy Obsessed with 1.5L Drives: '10 PW Yaris Sedan Join Date: Feb 2011 Location: Westminster, MD Posts: 907	Your maf housing is the incorrect diameter. If its any different then stock the readings are skewed. At least on our 1.5s the maf housing is 60mm-2 3/8" Yours is probably the same. Larger will run lean...smaller will run rich __________________ -Greg...the Exhaust Freak. -10 PW sedan 107whp/110wtq, full exhaust, suspension bits, TRD LSD -06 Highlander 3mzfe Limited AWD -82 Malibu, 1uzfe swap -97 Tercel coupe, 1nzfe/4.31 -96 Tercel coupe, Turbo 5efe, autoX -96 Tercel 4dr

08-23-2014, 05:47 PM	#7
why? Only Happy When it Rains View User's Garage Drives: Yaris LB Join Date: Jan 2006 Location: harnett county NC Posts: 4,097	Did you unplug the battery to reset everything after you installed the intake? But malibuguy is probably right. The Yaris is extremely sensitive to any changes. And MAF sensors can't deal with changes at all. __________________ Colin Chapman disciple

09-06-2014, 09:01 PM	#12
malibuguy Obsessed with 1.5L Drives: '10 PW Yaris Sedan Join Date: Feb 2011 Location: Westminster, MD Posts: 907	Im telling you from experience you need to change the maf housing to 2 3/8" /60mm The stock computer does not have that kind of compensation built into it. Think about it...why the hell would the programmers waste time to create mappings for the off chance someone does incorrect modifications to the car?? __________________ -Greg...the Exhaust Freak. -10 PW sedan 107whp/110wtq, full exhaust, suspension bits, TRD LSD -06 Highlander 3mzfe Limited AWD -82 Malibu, 1uzfe swap -97 Tercel coupe, 1nzfe/4.31 -96 Tercel coupe, Turbo 5efe, autoX -96 Tercel 4dr

08-23-2014, 05:40 PM	#6
268i Drives: 06' Yaris 1.3l Join Date: Jul 2014 Location: NZ Posts: 46	Also worth noting that the first time I started the car i revved it a little and it got to around4000rpm but then the revs just slowly went down to zero

08-23-2014, 06:14 PM	#8
Exiwolfman View User's Garage Drives: 2007 Yaris Join Date: Feb 2013 Location: Wasaga beach Posts: 1,617	sounds like a vacuum leak , u sure u have everything connected right sensor facing the right way etc...

08-24-2014, 03:34 AM	#10
268i Drives: 06' Yaris 1.3l Join Date: Jul 2014 Location: NZ Posts: 46	I might try doing it again next weekend. I'll remove the battery this time and see how it goes. A friend of mine who did something similar said it ran quite rich for the first day or so.. Anyway.. Does the repeated experimenting with the setup (and causing the engine to turn itself of) pose any risks of damaging my engine?

09-06-2014, 06:40 PM	#11
268i Drives: 06' Yaris 1.3l Join Date: Jul 2014 Location: NZ Posts: 46	Update: Battery removed this time and it seemed to shut off quite quickly. I've learnt from someone thats done this before that when the engine shakes I should leave it for the ECU to learn airflow as a result of it changing and to give it a little bit of gas if its really going to shut off. However, It was pretty much impossible for me to give it a little bit of revs before the engine just cut off..

09-06-2014, 09:04 PM	#13
malibuguy Obsessed with 1.5L Drives: '10 PW Yaris Sedan Join Date: Feb 2011 Location: Westminster, MD Posts: 907	I had a xB1...same motor...I originally fabbed an cold air intake using 2.5" piping and it ran lean and had no power. Switch to 2.25" and it ran rich...measured the maf and realized what I needed to do. So I made a 2 3/8" housing and it ran beautiful. The ecu is expecting only to see a basic range of parameters thru that sensor. The wrong size housing only skews what it thinks it is seeing __________________ -Greg...the Exhaust Freak. -10 PW sedan 107whp/110wtq, full exhaust, suspension bits, TRD LSD -06 Highlander 3mzfe Limited AWD -82 Malibu, 1uzfe swap -97 Tercel coupe, 1nzfe/4.31 -96 Tercel coupe, Turbo 5efe, autoX -96 Tercel 4dr

09-06-2014, 09:27 PM	#14
fnkngrv Mr. 155 and climbing View User's Garage Drives: Seriously Modded 07 Sedan Join Date: Jun 2006 Location: In The Hotbox Posts: 4,742	I was so glad when I ditched MAF. it has its place, but man it can be a PITA. __________________ Team Tiamat Racing on Facebook Youtube Channel: Team Tiamat Racing *Class record holder in Land Speed @ 154.5mph for 1.5 mile and 145.5mph in the mile in the F (2.016 to 3.014 L), G (1.524 to 2.015 L), and H (1.016 to 1.523 L) classes.* Last edited by fnkngrv; 09-07-2014 at 12:36 AM.

09-06-2014, 11:08 PM	#15
Bluevitz-rs 1NZ-6spd View User's Garage Drives: '05 6-Spd Vitz RS Join Date: Oct 2008 Location: Oshawa, Ontario, Canada Posts: 2,967	x2 on the 2-⅜" MAF housing. The ECU will not compensate for any deviances in that diameter. It has absolutely no reason to either as Toyota engineered it to work with the stock air box and know exactly how much air flows by the MAF. Increasing the size of the pipe increases volume but decreases velocity, so the ECU see less air going into the engine and gives less fuel. There is no reason to increase it's size to try and get more air into the engine unless you've done MAJOR engine work and require it because you have a massive throttle body and it's opening is now bigger than the intake piping.

09-07-2014, 02:05 AM	#17
268i Drives: 06' Yaris 1.3l Join Date: Jul 2014 Location: NZ Posts: 46	Thanks everyone for advice. I bought the 3" housing all ready for the toyota MAF sensor and the company (spectre) only seem to make 3".. Might have to DIY with PVC Piping then..

09-07-2014, 08:34 AM	#18
Exiwolfman View User's Garage Drives: 2007 Yaris Join Date: Feb 2013 Location: Wasaga beach Posts: 1,617	Honestly don't get why u would have problem with size of piping cos when running a CAI on my Yaris with a 3 inch piping that shrinks down to 2.25 at throttle body it all works fine ...same as my Sri home made intake ...I say u have an issue with ur sensor . Anyhow I see u got new piping let us know how it goes. sent from my S4 on Mars