NA-T Questions?? Ask the Guru
That sounds good then, are you running the heated o2 sensor. not sure why its doing that exactly.
That is a common place to have a leak, try using a new oem gasket and I put a stud on the last bolt of the lower runner to help align the gasket and the manifold as you are putting it on.
Alot of people get it welded for that reason, but I didn't seem to have any leaks when I did mine a couple times.
That is a common place to have a leak, try using a new oem gasket and I put a stud on the last bolt of the lower runner to help align the gasket and the manifold as you are putting it on.
Alot of people get it welded for that reason, but I didn't seem to have any leaks when I did mine a couple times.
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That sounds good then, are you running the heated o2 sensor. not sure why its doing that exactly.
That is a common place to have a leak, try using a new oem gasket and I put a stud on the last bolt of the lower runner to help align the gasket and the manifold as you are putting it on.
Alot of people get it welded for that reason, but I didn't seem to have any leaks when I did mine a couple times.
That is a common place to have a leak, try using a new oem gasket and I put a stud on the last bolt of the lower runner to help align the gasket and the manifold as you are putting it on.
Alot of people get it welded for that reason, but I didn't seem to have any leaks when I did mine a couple times.
For mine i used my air compressor, filled the tank and shut it off and pressurized the intake using one of the vac lines, this showed me where all the leaks were lol
I filled the intake manifold with a ALOT of vape smoke, via brake booster hose, and I couldn’t see any smoke.
I used thread sealant on all the NPT threads on the ffim, so I pretty sure those are good to go.
I’m gonna swap in my extra aristo ecu and see what happens.
Any other suggestions? (Erratic idle, random stalling, and I reach 19 psi without boost cut)
Gotcha, its already welded and talking intake to head. Hard to say without being there you'll have to look everything over when it comes to leaks.
What is your vacuum and rpm at idle when its normal?
Could be a leak, could be a coilpack issue, vvti coils can be picky and have heard of them causing it to be rich. could also be an ecu issue.
Does your check engine light work, does it have any codes? also sounds like your o2 sensor isn't working right, did you install the heated one?
What is your vacuum and rpm at idle when its normal?
Could be a leak, could be a coilpack issue, vvti coils can be picky and have heard of them causing it to be rich. could also be an ecu issue.
Does your check engine light work, does it have any codes? also sounds like your o2 sensor isn't working right, did you install the heated one?
Yes, heated 02 installed (did it wrong the first time and it caused a lean idle. Fix that and now lean idle is gone).
CEL works and no codes.
When engine is warmed up, idle is around 800.. 900
Not sure, “What is your vacuum?” means. I did put my palm on the throttle body while the car was idling and my hand almost got sucked in.
Thanks for the info. I’m gonna swap in some Denso coil packs too.
CEL works and no codes.
When engine is warmed up, idle is around 800.. 900
Not sure, “What is your vacuum?” means. I did put my palm on the throttle body while the car was idling and my hand almost got sucked in.
Thanks for the info. I’m gonna swap in some Denso coil packs too.
all of that sounds normal for the most part. do you have an idle control valve?
when that o2 wire previously shorted it could have damaged the ecu. I would try the spare ecu first if you have one, that might be it.
if not check over the coilpacks and plugs.
vacuum as in whats your boost gauge reading at idle, assuming its a vaccum/boost gauge.
If you are used to looking at it you can notice when there is a vacuum leak itll show up different on the gauge.
This is sort of the reason why I tell people to install the tt ecu first and then do a ffim. doing both at once makes it hard to track down issues.
when that o2 wire previously shorted it could have damaged the ecu. I would try the spare ecu first if you have one, that might be it.
if not check over the coilpacks and plugs.
vacuum as in whats your boost gauge reading at idle, assuming its a vaccum/boost gauge.
If you are used to looking at it you can notice when there is a vacuum leak itll show up different on the gauge.
This is sort of the reason why I tell people to install the tt ecu first and then do a ffim. doing both at once makes it hard to track down issues.
Boost gauge doesn’t reading anything at idle.
I had the TT ecu mod done running fine before anything. Then installed ffim exactly how you wrote it up. Pretty much exactly like your last ffim you put together.
I had the TT ecu mod done running fine before anything. Then installed ffim exactly how you wrote it up. Pretty much exactly like your last ffim you put together.
Usually they have vacuum also but some of the boost gauges don't. the vacuum is handy for telling if something is off after you get used to it.
If it was running fine before then I would guess its not the coilpacks. if it was running fine after fixing the o2 then its not that either.
So it has to be a leak or something up with the intake manifold. The adjustment of the tps with the q45 throttle body is tricky, and even though you are in the right range could be too far away from the transition point possibly.
So I would lean towards the intake leaking somewhere or the tps. make sure the wires are good on the tps connector, they tend to crack and break.
Other than the throttle body/tps setup the FFIM shouldn't change a whole lot with how it runs.
And these cars also run lean after a hot start for like 30 seconds then it clears up or with some throttle input, that is normal after a hot start, but it shouldn't happen while you have been driving some.
If it was running fine before then I would guess its not the coilpacks. if it was running fine after fixing the o2 then its not that either.
So it has to be a leak or something up with the intake manifold. The adjustment of the tps with the q45 throttle body is tricky, and even though you are in the right range could be too far away from the transition point possibly.
So I would lean towards the intake leaking somewhere or the tps. make sure the wires are good on the tps connector, they tend to crack and break.
Other than the throttle body/tps setup the FFIM shouldn't change a whole lot with how it runs.
And these cars also run lean after a hot start for like 30 seconds then it clears up or with some throttle input, that is normal after a hot start, but it shouldn't happen while you have been driving some.
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Usually they have vacuum also but some of the boost gauges don't. the vacuum is handy for telling if something is off after you get used to it.
If it was running fine before then I would guess its not the coilpacks. if it was running fine after fixing the o2 then its not that either.
So it has to be a leak or something up with the intake manifold. The adjustment of the tps with the q45 throttle body is tricky, and even though you are in the right range could be too far away from the transition point possibly.
So I would lean towards the intake leaking somewhere or the tps. make sure the wires are good on the tps connector, they tend to crack and break.
Other than the throttle body/tps setup the FFIM shouldn't change a whole lot with how it runs.
And these cars also run lean after a hot start for like 30 seconds then it clears up or with some throttle input, that is normal after a hot start, but it shouldn't happen while you have been driving some.
If it was running fine before then I would guess its not the coilpacks. if it was running fine after fixing the o2 then its not that either.
So it has to be a leak or something up with the intake manifold. The adjustment of the tps with the q45 throttle body is tricky, and even though you are in the right range could be too far away from the transition point possibly.
So I would lean towards the intake leaking somewhere or the tps. make sure the wires are good on the tps connector, they tend to crack and break.
Other than the throttle body/tps setup the FFIM shouldn't change a whole lot with how it runs.
And these cars also run lean after a hot start for like 30 seconds then it clears up or with some throttle input, that is normal after a hot start, but it shouldn't happen while you have been driving some.
It took me days to get that set right cause the adapter looses the stock adjustment range.
I would do it like this, I close the throttle blade more or less all the way (screw not touching/backed out), and then crack it a hair (turn screw in till its barely moving the plate)... and I mean barely cracked here, just enough to not want to catch/stick but it should be pushing against it slightly.
Then adjust the tps to where the pins are just barely engaged like we talked about before, and any more engaging of the tps results in the idle going to crap, set it right before that.
This should work well when using an IACV. If you don't have an idle valve and need to crack the throttle body more, you can turn the throttle screw but you have to go back and move the tps back that same amount or it will not be before the idle transition anymore. So you crack it open to what you need (like to maintain a decent cold idle without hte warm being way to high), and then go back and set the tps again. basically anytime you touch that idle screw, you need to make sure the tps is sitting right, as the idle/throttle screw moves the blade which moves the tps also.
maybe when you cracked the throttle open some more you didn't turn back the tps? that can cause the issue you are describing.
I would do it like this, I close the throttle blade more or less all the way (screw not touching/backed out), and then crack it a hair (turn screw in till its barely moving the plate)... and I mean barely cracked here, just enough to not want to catch/stick but it should be pushing against it slightly.
Then adjust the tps to where the pins are just barely engaged like we talked about before, and any more engaging of the tps results in the idle going to crap, set it right before that.
This should work well when using an IACV. If you don't have an idle valve and need to crack the throttle body more, you can turn the throttle screw but you have to go back and move the tps back that same amount or it will not be before the idle transition anymore. So you crack it open to what you need (like to maintain a decent cold idle without hte warm being way to high), and then go back and set the tps again. basically anytime you touch that idle screw, you need to make sure the tps is sitting right, as the idle/throttle screw moves the blade which moves the tps also.
maybe when you cracked the throttle open some more you didn't turn back the tps? that can cause the issue you are describing.
Swaped in another, recently serviced, artisto ecu and the car took awhile to start and when it did it seemed like it was misfiring bad and then stalled.
Swap back in the working ecu and now the wide band is showing it running completely lean. AFR is 18... even when it completely warms up.
What could’ve happened? Can a WB sensor get fouled?
Swap back in the working ecu and now the wide band is showing it running completely lean. AFR is 18... even when it completely warms up.
What could’ve happened? Can a WB sensor get fouled?
Last edited by joe diego; Apr 25, 2020 at 03:56 PM.
Wide band sensors can be damaged when starting if they get moisture on them and then powered up. That's why a lot of people put a delay on powering up the sensor so it is warmed or cleared before you power it up. Also, depending on the wb it might need a free air calibration, have not looked back through this thread to see what wb is being used. Hopefully that is not your issue, just saying possibilities.
Wide band sensors can be damaged when starting if they get moisture on them and then powered up. That's why a lot of people put a delay on powering up the sensor so it is warmed or cleared before you power it up. Also, depending on the wb it might need a free air calibration, have not looked back through this thread to see what wb is being used. Hopefully that is not your issue, just saying possibilities.
Again, I swaped in another, recently serviced, artisto ecu and the car took awhile to start and when it did it seemed like it was misfiring bad and then stalled.
Swap back in the working ecu and now the wide band is showing it running completely lean, even when it completely warms up. Shows lean almost instantly once WB turns on.
Can’t seem to find any exhaust leaks or vacuum leaks. Possibly fuel filter or fuel pump?
Tried 12v fuel mod with jumper and swaped in FP relay and still nothing.
AFRs were pretty good until I swaped ECUs back and forth once.
Last edited by joe diego; Apr 27, 2020 at 10:49 AM.
Did you do the tt headgasket, cant remember. if you did bump up your base timing right before 10 degrees, on the 9/10 edge, if not leave it around 8.
Are you running an IACV on the bottom of your intake? did you use the tt check valve, gasket, and oring? if not that can create a large boost leak.
Other than that it might be an intake to runner or runner to head leak, usually intake leaks would get compensated by the map sensor, but if is after the manifold and before the head it wouldn't.
The odd thing to me though is the video you posted a couple days back it looks like the factory o2 sensor is working cause its swinging up and down a whole afr point.. but it should be swinging around 14.5 to 15.5 and not as lean as it is. if it couldn't get to 14.7 it would probably max out towards it, and not be swinging like that.
That makes me think you could have an exhaust leak or issue with your wideband setup. not saying you do just it is a possibility.
do you have a pic of your wideband and o2 sensor location in the downpipe you can post.
also where are you sourcing your wastegate boost reference from, the turbo or the intake manfiold?
maybe a fresh cold start video to where it warms up would be useful.
I am more used to seeing and diagnosing how the car acts in person so sometimes seeing the symptom helps me figure it out alot quicker.
Are you running an IACV on the bottom of your intake? did you use the tt check valve, gasket, and oring? if not that can create a large boost leak.
Other than that it might be an intake to runner or runner to head leak, usually intake leaks would get compensated by the map sensor, but if is after the manifold and before the head it wouldn't.
The odd thing to me though is the video you posted a couple days back it looks like the factory o2 sensor is working cause its swinging up and down a whole afr point.. but it should be swinging around 14.5 to 15.5 and not as lean as it is. if it couldn't get to 14.7 it would probably max out towards it, and not be swinging like that.
That makes me think you could have an exhaust leak or issue with your wideband setup. not saying you do just it is a possibility.
do you have a pic of your wideband and o2 sensor location in the downpipe you can post.
also where are you sourcing your wastegate boost reference from, the turbo or the intake manfiold?
maybe a fresh cold start video to where it warms up would be useful.
I am more used to seeing and diagnosing how the car acts in person so sometimes seeing the symptom helps me figure it out alot quicker.