Sr20det lean during wot

[entrapm3nt]

Ok I've searched everywhere and still haven't found the exact issue. 1st gear usually pulls fine then once I get 2nd during wot it starts of 10s then starts to rise into the 13s. It runs lean before I hit max boost. It's a sr20det fully built. Here's some mods to help figure out my issue. 1000cc injectors, 340 aeromotive fuel pump, aeromotive fpr set at 55 at idle. Boost is set at 9 low 18 high. (It's possible my boost controller doesn't have current setings as I just got it) z32 maf, open bov, rs empathy tune, 270 cams, plugs gapped to .28. Changed new cts. Checked tps at 4.5v. Checked cas. Set ignition timing. Used consult and laptop still can't pinpoint issue. Any ideas here guys? I should have damn hear 500 hp with this set up. 4k in machine work. Car feels slow. Thanks in advance for your time.

[derass]

Maybe wiring to the fuel pump or some kind of restriction? Try to check it under load. I used a mechanical gauge tape to my wiper arm as I drove around.

I also had my AEM wideband sensor fail after a few years. I would read fine at idle but under load it would go max lean (display ---). Changed the sensor and it read fine. I used this test: https://www.youtube.com/watch?v=onbjzEOZtMs

[jr_ss]

If your pump isn't hardwired, that could be an issue. Usually the factory wiring can't keep up with the amperage demand under load on larger pumps and fuel systems causing the voltage to drop. Put a volt meter on your pump wires and see what it drops to. Under 12vs will cause issues with your fueling demands, especially injectors.

[dorkidori_s13]

Fuel pump wiring most likely. If youre on stock wiring, your pump is dropping voltage in higher RPMs as OE S-chassis wiring sucks and cannot carry proper current under higher loads (especially in a setup like yours). Run a relay directly from the battery back to the pump

[KAT-PWR]

What turbo?

[entrapm3nt]

My fuel pump is def using stock wiring and im guessing this is the issue. Im a big noob when it comes to wiring. I did however just wire in that fuel pump 2 days ago thinking the stock wiring would be fine.had a 255 walbro that i thought was going out. Anyways where do i find a relay to do this? Any write up on this? like i said im not great with wiring at all. I should also note i have a sort of cheap battery. Would upgrading my battery help as well? its in the trunk right near the fuel pump so this shouldnt be too hard but i have no idea where to start. thanks again guys.

to the other guy asking what turbo i have. not sure why that matters but its a GT2871R

[KAT-PWR]

I ask what kind of turbo because when someone makes claims like "should be near 500whp" and they're using a 400hp turbo (when pushed hard on a good tune) it shows what we're working with.

You can google around and find the "how to" for the fuel pump relay wiring.

[entrapm3nt]

I ask what kind of turbo because when someone makes claims like "should be near 500whp" and they're using a 400hp turbo (when pushed hard on a good tune) it shows what we're working with.

You can google around and find the "how to" for the fuel pump relay wiring.

Whoa no need to be rude. I was just saying the car should be fast and its super slow. And correct me if im wrong but i thought the 56 trim version of the gt2871r is good up to 475hp? Yes im aware of the "how to" videos. Im more just wondering what gauge wire to use, what relay etc. I lost the paperwork for the fuel pump i just put in that would have been very helpful. But yeah if i posted my mod list you would say the same thing. the engine "should" have near 500 hp. Anyways back to the fuel issue. Thank you everyone for your comments. Hopefully i can get this sorted out soon.

[brndck]

+1 for hard wire your fuel pump
(you'll need a dedicated relay, I use a dedicated fuse as well)

[dorkidori_s13]

pretty much the only fuel pump that doesnt lose voltage in higher power band ranges is the Walbro 255 (itll drop back a few PSI at most). but walbros are well known for their pissy lifespans if you run them below 1/4 of a tank as the pump will burn up due to improper cooling.

as brndck said above, run a dedicated relay from your battery to your fuel pump and youll be set. try to mount the relay somewhere in the trunk area where it will have ample venting room as they do tend to get quite hot (especially if youre running a larger fuel pump).

[Karlhammer]

Fused power with a relay is pretty much a must. and there's no exhaust leaks around the sensor that could be causing it to read false? do you have the ability to see what the stock sensor is seeing to compare? You should get a DMM and wire it up so when you're driving around you can see how much voltage the pump is getting.

[dorkidori_s13]

if you have a fuel pressure gauge, that will give you indication voltage dropping as well. if the fuel pressure dives in higher RPMs, it means your pump is most likely losing voltage.

i know for a fact on S13s, that aeromotive pump you has loses voltage at top end because i had one installed briefly while i was waiting on a new walbro. it would drop back roughly 10-15psi on fuel pressure via my gauge which is NOT good!!! my walbro only drops back 2-3 psi at most. its not a faulty pump either, its simply that the pump itself needs a full 12v going to and the OE wiring in S13s can only supply up to roughly 10-11v at max. the gauge of the wiring is too thin and cant push proper voltage, hence running a relay directly from battery to pump.

[Karlhammer]

What fuel pressure regulator are you runinng? We've seen fuel lab brand fail the most. Had a couple really old Aeromotive ones fail.

[Kingtal0n]

if you have a stand alone you max injector duty should correlate with power output, otherwise it is a fuel pump/feed issue

[entrapm3nt]

What fuel pressure regulator are you runinng? We've seen fuel lab brand fail the most. Had a couple really old Aeromotive ones fail.

I have a areomotive fpr thats brand new

if you have a stand alone you max injector duty should correlate with power output, otherwise it is a fuel pump/feed issue

I have a rom ecu. plan on going stand alone pretty soon.

[entrapm3nt]

So i bought all the stuff i need im going to wire it all up this weekend and let you guys know if it fixed the problem. Thanks :D

[entrapm3nt]

So i wired everything up perfect but my car is still going lean during wot. guess it was something else also. 1st gear no longer leans out but every other gear does. I was also thinking maybe my battery or alternator is maxing out. I had the aftermarket fan on, defrost, a double din, digital boost controller, and 5 digital gauges. I have like a 675cca napa battery. Would upgrading to a yellow top help? Only other thing i could think of is maybe timing or tune. basicly everything else is brand new.

[brndck]

What fuel pressure regulator are you runinng? We've seen fuel lab brand fail the most. Had a couple really old Aeromotive ones fail.

I have a areomotive fpr thats brand new
.
I had a BRAND NEW aeromotive take a shit on me. the diaphragm tore with only 40-50 miles on it, and it was sucking fuel through the vacuum hose, directly into my intake manifold. could easily have cost me an engine if it had hydrolocked.

aeromotive wouldn't warranty it either since I bought it off ebay. Had to spend another $50 to buy a new diaphragm. Its been fine ever since then.

Only other thing i could think of is maybe timing or tune. basicly everything else is brand new.
who tuned the car? I'm hoping they ran a wideband on it while tuning???

[entrapm3nt]

I had a BRAND NEW aeromotive take a shit on me. the diaphragm tore with only 40-50 miles on it, and it was sucking fuel through the vacuum hose, directly into my intake manifold. could easily have cost me an engine if it had hydrolocked.

aeromotive wouldn't warranty it either since I bought it off ebay. Had to spend another $50 to buy a new diaphragm. Its been fine ever since then.


who tuned the car? I'm hoping they ran a wideband on it while tuning???

its just a rs-enthalpy rom tune. The car hasnt been dyno tuned. I just sent it to him and he sent it back. A stand alone will be my next upgrade or maybe a power fc i haven't decided yet. That aeromotive statement you said is scary lol. Usually they have the best products thats why i went with them.

[jedi03]

plus one on lack of fuel...

[inopsey]

when was the last time you changed your fuel filter?

[entrapm3nt]

when was the last time you changed your fuel filter?

Yeah its a brand new z32 fuel filter probably 100 miles ago. Also changed cts, new maf, new spark plugs, new fpr, fuel pump and more I can't think of all in the past month

[entrapm3nt]

any other ideas why i would be going lean during wot? ive just been buying parts and throwing them at the car with no luck.

[KAT-PWR]

What brand injectors?

[dorkidori_s13]

well since youve rewired the fuel pump properly, i would say now that its down to the tune. ROM tunes are cute, but not worth it IMO. the amount of affordable stand alone ECUs on the market for the S13/S14 now is nuts... switching over to a PFC DJetro or AEM V2 would be highly recommended as you will be able to adjust areas of the tune that lean out to keep things stoich or even a little rich.

[dorkidori_s13]

also, have you run a proper boost leak test on your motor by slowly pressurizing your IC system? this could all boil down to a faulty coupler or clamp.

[entrapm3nt]

also, have you run a proper boost leak test on your motor by slowly pressurizing your IC system? this could all boil down to a faulty coupler or clamp.

Yes, i have done a boost test. although that was many months ago probably the first thing i checked. i may check again tho. i remember for some reason it was reading nothing but had to turn the engine over more to check the boost pressure correctly.

Also I just thought of something that could be it. When i was wiring up the relay i used one of those easy fuse harnesses with wires pre attached. Im thinking those wires were only 16ga. so all my 10ga wiring is going to it. could this effect anything even tho the wires are very short? i could just find some female plugs and run the 10ga directly to the fuse.

[entrapm3nt]

I also should add that my vacuum is reading about -15 inhg. but i was told that it was normal because of my 270/270 cams. Ive looked for leaks 100 times and found nothing.

[dorkidori_s13]

might just be as simple as your tune... ROM tunes are garbage, they dont account for variables in weather conditions based upon where you live. theyre also not tuned directly to your actual car... theyre tuned based on predetermined parameters that you give the tuner who creates the tune for the chip. running full stand alone lets you compensate for variables on YOUR motor as well as YOUR weather conditions.

in Vegas, if you tune your car at any point of the year other than in the middle of summer, your tune will lean out heavily in the heat. oxygen density is much less in the heat than it is in the cold. once a Vegas car is tuned in the summer properly, it will run perfectly year round! same goes for phoenix, tucson and any other spot on the planet that is basically hell on earth lol ;)

[entrapm3nt]

might just be as simple as your tune... ROM tunes are garbage, they dont account for variables in weather conditions based upon where you live. theyre also not tuned directly to your actual car... theyre tuned based on predetermined parameters that you give the tuner who creates the tune for the chip. running full stand alone lets you compensate for variables on YOUR motor as well as YOUR weather conditions.

in Vegas, if you tune your car at any point of the year other than in the middle of summer, your tune will lean out heavily in the heat. oxygen density is much less in the heat than it is in the cold. once a Vegas car is tuned in the summer properly, it will run perfectly year round! same goes for phoenix, tucson and any other spot on the planet that is basically hell on earth lol ;)

Good information. a new ecu is def on next on my list. as far as that gauge wire on the harness relay tho do you think that will be ok or should i replace it with 10ga?

[dorkidori_s13]

eh if youre gonna do it, might as well over do it ;)

[corkscrew]

Has it ever ran normal/better? If not, it's probably the tune. If it is, you should email Martin directly

[KAT-PWR]

Has it ever ran normal/better? If not, it's probably the tune. If it is, you should email Martin directly

this x10000

I'd make sure all your stuff is what it is expected to be, if a tune is running lean, and you have a rom tune for what you think your set up is, it should be rich if anything.
Look at what PSI fuel pressure your 1000cc injector were done at. If it was 4bar fuel pressure for 1kCC, this could be your issue

[jr_ss]

might just be as simple as your tune... ROM tunes are garbage.

I'd hardly call them garbage. Are they optimal? No. There are better ways to extrapolate more power, reliability and features out of your car, but for most people, a ROM tune is all that is needed. Not to mention, base tunes from your standalone are nothing more than a "predetermine parameter" tune anyway. You still have to put in the money and time on a dyno to dial it all in. Making power is the easy part. Making it reliable and tuning drivability is the hard part.

There have been plenty of people making big power on ROM tunes.

AEM < Haltech...

[entrapm3nt]

Has it ever ran normal/better? If not, it's probably the tune. If it is, you should email Martin directly

No it hasn't. Its been retuned 3 times from Martin. Ive emailed him and he has tried his best to help with the issue but everything he asks me to do ive done and still no go. Although it could just need a dyno tune. Im still going to get another ecu though. Im stuck between aem or power pc.

[entrapm3nt]

this x10000

I'd make sure all your stuff is what it is expected to be, if a tune is running lean, and you have a rom tune for what you think your set up is, it should be rich if anything.
Look at what PSI fuel pressure your 1000cc injector were done at. If it was 4bar fuel pressure for 1kCC, this could be your issue

I think they are 4 bar actually at 100%. Ill double check. Does this mean i should just turn my fuel pressure up? its already at 55 at idle with vac plugged in. Seems like a lot already. Im also thinking maybe my battery or alternator isnt keeping up with all the electronics im running. Since i added the relay to the fuel pump the car starts more slowly. before it started up very quickly. Like its giving all the power to the pump (it is but still)

[lok]

Can you verify voltage to the ecu via consult?

[entrapm3nt]

Can you verify voltage to the ecu via consult?

I can use consult. I can't remember if it shows ecu voltage tho. I have a regular volt gauge in the car. Its been a few weeks since ive used it. Ill check again and get an exact number. I can post a video of the screen then maybe one of you might see something i missed.

[corkscrew]

Any vacuum leaks at all? I had my ecu tuned and it was awesome. Then I got a small leak in my IACV gasket and it ran like complete ass until I fixed the vac leak

[entrapm3nt]

Any vacuum leaks at all? I had my ecu tuned and it was awesome. Then I got a small leak in my IACV gasket and it ran like complete ass until I fixed the vac leak

Its possible but ive checked multiple times and sprayed carb cleaner. Cant find anything. I got 2 gauges that read inhg. one says -15 other says -12. I know it should be -20 but its hard to tell where it really should be with my huge 270 cams.

[entrapm3nt]

Im at work right now but tomorrow im gonna post a video of my cars gauges and the consult screen to see if you guys notice something i didnt.

[entrapm3nt]

Here is a video I just took of me using consult. A knock sensor code popped up that wasn't there last time I used consult. Also it appears my timing is moving a lot. I set ignition timing recently to 15btdc. Is the knock sensor retarding my timing? Watch this short video maybe you will see something else I didnt.

https://youtu.be/N5XSVHohY_Q

[lok]

Car will run terrible with knock sensor code.

Still does explain the lean at WOT

Use 1 mega ohm resistor to bypass knock sensor and try again.

[entrapm3nt]

Car will run terrible with knock sensor code.

Still does explain the lean at WOT

Use 1 mega ohm resistor to bypass knock sensor and try again.

I don't feel comfortable bypassing a knock sensor. If it's retarding timing how would that not explain lean at wot?

[lok]

I don't feel comfortable bypassing a knock sensor. If it's retarding timing how would that not explain lean at wot?

Just use the resistor to see if you can get to run better til you can get a good knock sensor. Haha Not a permanent fix.

With the knock sensor code, the ECU should be using the knock fuel map which is really rich for safety.

[cotbu]

What is the brand of the injectors, mafs and cams?
Might be something in the tune.

Do you have access to some stock parts? Take a few steps backwards to move forward.

Was the engine tuned for e85, e70 or pump gas?

You have to set base idle and timing so do that. Clear the code enter timing mode set base idle and timing lock it down. Check codes. Make sure everything is good, timing stable vacuum strong(doesn't have to be 20inhg just steady)

Ps if you have bc cams let me know meow!

Yeah the tps, I'm assuming that was a typo but it should be .45v closed and 4.1~ wide open, the close you get to 5v you should adjust you closed voltage down abit. Let the ecu relearn.

Also your boost is not what I would consider high, even at 18psi your looking at 360-370 avg.

Sent from my SM-N910T using Tapatalk

[entrapm3nt]

What is the brand of the injectors, mafs and cams?
Might be something in the tune.

Do you have access to some stock parts? Take a few steps backwards to move forward.

Was the engine tuned for e85, e70 or pump gas?

You have to set base idle and timing so do that. Clear the code enter timing mode set base idle and timing lock it down. Check codes. Make sure everything is good, timing stable vacuum strong(doesn't have to be 20inhg just steady)

Ps if you have bc cams let me know meow!

Yeah the tps, I'm assuming that was a typo but it should be .45v closed and 4.1~ wide open, the close you get to 5v you should adjust you closed voltage down abit. Let the ecu relearn.

Also your boost is not what I would consider high, even at 18psi your looking at 360-370 avg.

Sent from my SM-N910T using Tapatalk

Hate to bump a kinda old thread but im still having the same issue. to answer your questions. 1000cc five-o injectors, brand new z32 maf, tomei 270/270 cams. tuned for pump gas. Also i could probably handle 25 psi if i didnt lean out. Since my last post i MAY have found the problem. Im running a vented catch can that doesnt go back into the intake. ive ordered a new valve cover and cheap catch can to run a sealed set up going back to the intake. Could this be the cause of my lean issue during wot? Thanks again for everyones time.

[cotbu]

What have you done since the last time this thread was active? Take the catch can out of the equation, by running a line to the turbos intake, if possible. (Valve cover to turbo intake)

Get the engine up to operating temperature. That means keeping it alive anyway you can. (80°c or 176°f) then put the ecu into timing mode. Set idle and timing. Make sure there are no codes store or thrown. If you did a boost leak test and air was escaping from the catch can, it may have been part of the problem, aka you should have been richer.
You may also try testing the wideband sensor. Make sure it's functioning properly.

[entrapm3nt]

What have you done since the last time this thread was active? Take the catch can out of the equation, by running a line to the turbos intake, if possible. (Valve cover to turbo intake)

Get the engine up to operating temperature. That means keeping it alive anyway you can. (80°c or 176°f) then put the ecu into timing mode. Set idle and timing. Make sure there are no codes store or thrown. If you did a boost leak test and air was escaping from the catch can, it may have been part of the problem, aka you should have been richer.
You may also try testing the wideband sensor. Make sure it's functioning properly.

I haven't done anything. I can't run a line from valve cover to turbo intake. I have a custom valve cover that's why I ordered a new one. I have already set timing recently. It's correct. Only code I got was knock sensor and I replaced it. My wideband has is new and it's aem it's working fine. I haven't checked codes since after I cleared the knock senor after I replaced it. (Knock sensor tested bad per fsm.) It's possible the code could have came back I'll double check but like I said I replaced the sensor and deleted code.

[cotbu]

After that code did you check timing again?

[entrapm3nt]

After that code did you check timing again?

Yes timing and tps were the last things I did.

[entrapm3nt]

So could my unmetered air from my catch can not recirculating be the cause of my lean at wot issue? Or would it make me even more lean?

[cotbu]

I'd like to see your engine bay. And try this after you get you car to operating temp, pull the fuel pump fuse, take video of course, capture until it dies. Trying to see if it smooths out any.

[entrapm3nt]

I'd like to see your engine bay. And try this after you get you car to operating temp, pull the fuel pump fuse, take video of course, capture until it dies. Trying to see if it smooths out any.

I can definitely show you pictures. Not sure why you think it would smooth out from pulling the fuel pump fuse. I've done it before and it just dies like it should. Give me a few minutes and I'll post a picture.

[entrapm3nt]

http://i66.tinypic.com/so3ard.jpg

[cotbu]

That catch can setup is ummmm yeah.
Are your injectors touching the intake manifold?
If you pull the fuel pump fuse, and your idle and timing corrects before it shuts down, it's probably the tune. Now I only came to that conclusion based on the video, so if things changed my bad. I couldn't really anything over the exhaust.

Does your timing still jump around like in the video, You may have to fix that. It should be way more steady, it might follow the rpm a few degrees up and down, but not like that.

If you believe timing is correct, along with the tune and you have only that catch can/valve cover setup to change. I hope that fixes it.

[entrapm3nt]

That catch can setup is ummmm yeah.
Are your injectors touching the intake manifold?
If you pull the fuel pump fuse, and your idle and timing corrects before it shuts down, it's probably the tune. Now I only came to that conclusion based on the video, so if things changed my bad. I couldn't really anything over the exhaust.

Does your timing still jump around like in the video, You may have to fix that. It should be way more steady, it might follow the rpm a few degrees up and down, but not like that.

If you believe timing is correct, along with the tune and you have only that catch can/valve cover setup to change. I hope that fixes it.

Yeah that video is old is idles smooth at 1k with 13 afr at about -15 inhg. I forgot I even posted a video. It runs and drives fine until you hit floor it. Just don't really drive it much. Yes hopefully it's the catch can. I got everything together just need to figure out how to add a nipple on my turbo intake. Hopefully it fixes it if not I'm gonna get a stand alone ecu.