I hate my car
11-30-12, 11:21 AM
#1
I hate my car
I'm really starting to hate my SC4.
I bought the car awhile ago, and dreamed of going manual. So since I've finally worked my way up to the ranks, and the manual swap was starting to go for cheap, I pieced together a five speed swap, and finally went five speed.
Then dreamed of going Supercharged, came across a good deal for a complete supercharger with fish bracket, and here I am.
My car idles like crap, gets pretty bad gas mileage, and bucks, and shakes.
I've virtually have replaced all sensors (just did the cam sensors today), the only ones I haven't replaced are TPS, and the crank sensor. My car still runs like crap, and the only codes it throws is for the EGR.
I have no idea what the hell is going on with it, and I wanna set it ablaze.
/end rant
I bought the car awhile ago, and dreamed of going manual. So since I've finally worked my way up to the ranks, and the manual swap was starting to go for cheap, I pieced together a five speed swap, and finally went five speed.
Then dreamed of going Supercharged, came across a good deal for a complete supercharger with fish bracket, and here I am.
My car idles like crap, gets pretty bad gas mileage, and bucks, and shakes.
I've virtually have replaced all sensors (just did the cam sensors today), the only ones I haven't replaced are TPS, and the crank sensor. My car still runs like crap, and the only codes it throws is for the EGR.
I have no idea what the hell is going on with it, and I wanna set it ablaze.
/end rant
11-30-12, 11:53 AM
#2
egr code can get tripped due to the higher EGT's that a supercharged car is going to see, I got the same thing when I went turbo on my sc3, its not a huge deal but you can block the flow to make sure thats not the cause as a test.
where is your maf? post up a picture maybe.
do you have a bypass valve installed? it could have alot to do with that and your maf setup and it has to be recirculated properly, otherwise the ecu will have no chance at figuring out whats going on.
at the least disconnect your main o2 sensors and reset your ecu. need more info on the setup details im sure you can get it figured out. I wouldn't be replacing sensors chances are if there is no CEL they wouldn't just stop working from a supercharger. I am almost certain its your ecu getting confused for some reason. my car was hardly driveable on my stock ecu before getting everything setup just right, and you make boost in all rpm ranges so its probably worse.
where is your maf? post up a picture maybe.
do you have a bypass valve installed? it could have alot to do with that and your maf setup and it has to be recirculated properly, otherwise the ecu will have no chance at figuring out whats going on.
at the least disconnect your main o2 sensors and reset your ecu. need more info on the setup details im sure you can get it figured out. I wouldn't be replacing sensors chances are if there is no CEL they wouldn't just stop working from a supercharger. I am almost certain its your ecu getting confused for some reason. my car was hardly driveable on my stock ecu before getting everything setup just right, and you make boost in all rpm ranges so its probably worse.
11-30-12, 12:00 PM
#4
Ali,
Thanks for the reply, sorry I posted it all up really fast cause I was about to set the SC on fire. Fortunately the gas station has a minimum purchase of ten dollars on a credit card, and didn't want to spend too much money on gas to set it ablaze.
The KMV sensor used to be a blow through setup, what happens is that the sensor sees positive pressure it will start to LIFT the sensor. So all the boosted 1uz guys either put JB weld on the sensor, or relocate it to the other side.
So I moved it to the other side, I extended the harness and triple checked my wiring. However the car ran the same before and after I relocated the sensor. I assumed since the sensor was getting it's internals lifted was the cause of why the car ran poorly.
So even as a pull through setup it's still running the same. I am currently running a blow off valve, but I don't see why that would be cause it to surge at part throttle. The problem is when I'm just cruising the car is bucking and surging, WOT is fine.
I can watch my wideband dance from 12->15:1 AFR's.
The only time the car runs well when it's cold or when the KMV is disconnected. When the car is cold it runs decent, when t he KMV is disconnected it runs awesome. And I have replaced the CTS.
I could understand if the car was stalling in between shifts, or even stumbling since it's blowing out metered air, but this isn't the case. The car just runs poorly overall.
Thanks for the reply, sorry I posted it all up really fast cause I was about to set the SC on fire. Fortunately the gas station has a minimum purchase of ten dollars on a credit card, and didn't want to spend too much money on gas to set it ablaze.
The KMV sensor used to be a blow through setup, what happens is that the sensor sees positive pressure it will start to LIFT the sensor. So all the boosted 1uz guys either put JB weld on the sensor, or relocate it to the other side.
So I moved it to the other side, I extended the harness and triple checked my wiring. However the car ran the same before and after I relocated the sensor. I assumed since the sensor was getting it's internals lifted was the cause of why the car ran poorly.
So even as a pull through setup it's still running the same. I am currently running a blow off valve, but I don't see why that would be cause it to surge at part throttle. The problem is when I'm just cruising the car is bucking and surging, WOT is fine.
I can watch my wideband dance from 12->15:1 AFR's.
The only time the car runs well when it's cold or when the KMV is disconnected. When the car is cold it runs decent, when t he KMV is disconnected it runs awesome. And I have replaced the CTS.
I could understand if the car was stalling in between shifts, or even stumbling since it's blowing out metered air, but this isn't the case. The car just runs poorly overall.
11-30-12, 02:31 PM
#5
your blow off valve is 100% the problem if its currently vented to atmosphere and not being recirculated.
what kind of BOV are you using and is it recirculated?
the worst part about blowthrough is that the frequency it outputs in boost has nothing to do with how much actual airflow is there anymore, because when Toyota used these mafs on the 7mgte, it was in a draw through for this very reason. I had it in blowthrough for a while, but it wasn't ideal.
the key is to have it in draw through, so maf far as you can get it in front of supercharger closer to the air cleaner, and you must use a recirculating bypass valve for a supercharger, that plumbs back into the intake pipe as close to the supercharger inlet as possible. this allows for no metered air to escape, and to not have positive pressure from the supercharger at idle (i think).
what kind of BOV are you using and is it recirculated?
the worst part about blowthrough is that the frequency it outputs in boost has nothing to do with how much actual airflow is there anymore, because when Toyota used these mafs on the 7mgte, it was in a draw through for this very reason. I had it in blowthrough for a while, but it wasn't ideal.
the key is to have it in draw through, so maf far as you can get it in front of supercharger closer to the air cleaner, and you must use a recirculating bypass valve for a supercharger, that plumbs back into the intake pipe as close to the supercharger inlet as possible. this allows for no metered air to escape, and to not have positive pressure from the supercharger at idle (i think).
Last edited by Ali SC3; 11-30-12 at 02:37 PM.
11-30-12, 02:48 PM
#6
I don't think so Ali, the main reason is because the BOV doesn't leak at idle. I've checked it numerous times thinking it was the problem.
The biggest problem with draw though with the SC setup is because we really don't have a lot of space to work with it.
This isn't my car, but take a look at it to see how much space we're working with. This is a pic of Sean's /SPF Lexus' car. He was running his KMV blow through at this time.
http://i222.photobucket.com/albums/d...s/DSCN1138.jpg
I'm going to run some piping around outside of the car to see how far I can put the KMV and see if the distance will make that much of a difference. I know it does because of the turbulence etc etc, but lets see if adding piping will make it better.
The biggest problem with draw though with the SC setup is because we really don't have a lot of space to work with it.
This isn't my car, but take a look at it to see how much space we're working with. This is a pic of Sean's /SPF Lexus' car. He was running his KMV blow through at this time.
http://i222.photobucket.com/albums/d...s/DSCN1138.jpg
I'm going to run some piping around outside of the car to see how far I can put the KMV and see if the distance will make that much of a difference. I know it does because of the turbulence etc etc, but lets see if adding piping will make it better.
11-30-12, 03:02 PM
#7
I remember reading a thread on Lextreme where someone tried to install a BOV and had problems. Everyone suggested that the person used a bypass valve instead. I was reading also how a BOV is kind of unnecessary for the centrifugal supercharged setup.
I tried searching on Lextreme where I read this but I couldn't find it. The thead is there though lol.
I tried searching on Lextreme where I read this but I couldn't find it. The thead is there though lol.
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12-01-12, 08:02 PM
#8
Changed all timing sensors and no dice. So I did make some progress, I was running without an air filter because it sat in the front bumper with nowhere else to go, I moved the KMV sensor as best as I could where it sat outside of the engine for temporary testing.
I noticed that my air filter adapter had a hole on the tube. So I placed my hand over the opening of the MAF adapter, and the car began to run better. I added a filter, and plugged the hole on the bottom and bam!
Super good idle. She idles at 13:1, and drives much better, but still not good. It's still bucking and studder, but so much better.
So the KMV sensor sits in the original location (under the driver's side headlight), and the filter portion sits behind the intercooler. I wonder if need to move the KMV sensor further away from the blower. The only problem is that space is VERY limited. I have no idea what else I can do though.
I noticed that my air filter adapter had a hole on the tube. So I placed my hand over the opening of the MAF adapter, and the car began to run better. I added a filter, and plugged the hole on the bottom and bam!
Super good idle. She idles at 13:1, and drives much better, but still not good. It's still bucking and studder, but so much better.
So the KMV sensor sits in the original location (under the driver's side headlight), and the filter portion sits behind the intercooler. I wonder if need to move the KMV sensor further away from the blower. The only problem is that space is VERY limited. I have no idea what else I can do though.
12-01-12, 08:05 PM
#9
Changed all timing sensors and no dice. So I did make some progress, I was running without an air filter because it sat in the front bumper with nowhere else to go, I moved the KMV sensor as best as I could where it sat outside of the engine for temporary testing.
I noticed that my air filter adapter had a hole on the tube. So I placed my hand over the opening of the MAF adapter, and the car began to run better. I added a filter, and plugged the hole on the bottom and bam!
Super good idle. She idles at 13:1, and drives much better, but still not good. It's still bucking and studder, but so much better.
So the KMV sensor sits in the original location (under the driver's side headlight), and the filter portion sits behind the intercooler. I wonder if need to move the KMV sensor further away from the blower. The only problem is that space is VERY limited. I have no idea what else I can do though.
I noticed that my air filter adapter had a hole on the tube. So I placed my hand over the opening of the MAF adapter, and the car began to run better. I added a filter, and plugged the hole on the bottom and bam!
Super good idle. She idles at 13:1, and drives much better, but still not good. It's still bucking and studder, but so much better.
So the KMV sensor sits in the original location (under the driver's side headlight), and the filter portion sits behind the intercooler. I wonder if need to move the KMV sensor further away from the blower. The only problem is that space is VERY limited. I have no idea what else I can do though.
Don't lose faith! I've always wanted a vortech setup.
12-02-12, 08:15 PM
#12
i told you what the problem was you are metering the air and then that hole and the bov are just letting it out.
I have alot of experience with toyota ecu's which is why its the first thing I asked. the stock intake system is a completely sealed system.
when using a KVM maf, you have to keep it that way in draw through and its the only way your car will run properly.
you are just talking about at one scenario being bad and all the rest being alright, but they are all directly related to the ecu trims.
When you let out air the ecu adjusts alot in the wrong direction all across the board, you could be idling after that or doing any number of things, and your air fuel will be completely off. when you seal the intake system and recirculate, the ecu will run fine for up to 7 lbs of boost people have been doing it for a long time.
These ecu's always sort of run alright when wot even when the trims are off because the ecu just dumps alot of fuel at that point in open loop.
what kind of bov do you have, I am still not sure if you are recirculating or not, if you are maybe we can figure out what else it can be.
if you aren't recirculating I can tell you its not helping.
I have alot of experience with toyota ecu's which is why its the first thing I asked. the stock intake system is a completely sealed system.
when using a KVM maf, you have to keep it that way in draw through and its the only way your car will run properly.
you are just talking about at one scenario being bad and all the rest being alright, but they are all directly related to the ecu trims.
When you let out air the ecu adjusts alot in the wrong direction all across the board, you could be idling after that or doing any number of things, and your air fuel will be completely off. when you seal the intake system and recirculate, the ecu will run fine for up to 7 lbs of boost people have been doing it for a long time.
These ecu's always sort of run alright when wot even when the trims are off because the ecu just dumps alot of fuel at that point in open loop.
what kind of bov do you have, I am still not sure if you are recirculating or not, if you are maybe we can figure out what else it can be.
if you aren't recirculating I can tell you its not helping.
Last edited by Ali SC3; 12-02-12 at 08:23 PM.
12-03-12, 08:17 AM
#15
Hey sorry all for the super short update last night, I got home a little late and was tired.
So I drove to Austin and back from Waco (about an hour and a half drive one way). The car ran decently well still bucked and stuff.
On the way back it got a little worse, and ate gas like nobodies business.
So I've noticed that in town driving is much better than highway cruising.
Ali SC3, I have a question for you.
I remember when I had a 1uz swapped MKIII (which was turbo'ed), when I disconnected the main o2's it would stay at about 12.5:1 (or maybe even 12:1), do you think I should just go ahead and get them disconnected? I'm not using anything for tuning at the moment since I'm trying to figure it all out.
Today when I drove home (about an hour from Waco), I stayed out of boost completely (but I also did so yesterday), and it seemed to correct the fuel trims a little better by the end of my trip it got a little better, then would get worse (by going back to how it was). Since I wasn't getting into boost, there wasn't any unmetered air getting let loose via the BOV.
I'm not sure what the ideal distance for the KMV sensor to the SC, but I'm going to assume it's like a MAF based car which is about a foot.
So I drove to Austin and back from Waco (about an hour and a half drive one way). The car ran decently well still bucked and stuff.
On the way back it got a little worse, and ate gas like nobodies business.
So I've noticed that in town driving is much better than highway cruising.
Ali SC3, I have a question for you.
I remember when I had a 1uz swapped MKIII (which was turbo'ed), when I disconnected the main o2's it would stay at about 12.5:1 (or maybe even 12:1), do you think I should just go ahead and get them disconnected? I'm not using anything for tuning at the moment since I'm trying to figure it all out.
Today when I drove home (about an hour from Waco), I stayed out of boost completely (but I also did so yesterday), and it seemed to correct the fuel trims a little better by the end of my trip it got a little better, then would get worse (by going back to how it was). Since I wasn't getting into boost, there wasn't any unmetered air getting let loose via the BOV.
I'm not sure what the ideal distance for the KMV sensor to the SC, but I'm going to assume it's like a MAF based car which is about a foot.
