SR20DET not revving past 4.5k rpm

[Shirohige]

SOLUTION
I WIRED THE PLUG WRONG. (SR20 PLUG TO CA18 PLUG) THERE IS A RED WIRE THAT WAS WIRED WRONG. THE VOLTAGE ON IT WAS 60V FOR SOME REASON. MOVED THE WIRE WHERE IT SHOULD BE AND THE CAR FIRED UP AND I COULD REV.

HOW TO FIND OUT? MEASURE THE VOLTAGE ON YOUR INJECTORS. PUT YOUR KEY IN THE ON POSITION AND MEASURE THE VOLTAGE ON THE RED WIRE(INJECTOR WIRE). MINE WAS AROUND 6V WITH STOCK ECU AND 60V (LEGIT) WITH MY POWER FC. IT WAS ALL BECUASE OF THAT ****************** WIRE

So my car isn't idle. I started my car after 1,5 years with a apexi power fc D-jetro. (map sensor) Also, its a sr20det redtop from a silvia s13.

The car is shaking a lot and it is between 900-1200rpm. I first thought it was running on 3 cilinders, but it isnt. all 4 of them are working. I didn't finish the self-learning process yet. I did it for almost 20 minutes. Can't go on since my car is in a public garage (which has open doors) underneath the houses and people will get mad if I do this at night.

Anyway after 20 minutes there was no change at all. Things i've done:|
555cc injectors ( 66%, 0,70ms)
S15 turbo
Map sensor (which has a vacuum line to the throttle body, on one of the ports above)


I've deleted the old map that was on it.

Im gonna look for vacuum leaks tomorrow. IACV should be fine since it was running fine before, i'll check that one out tomorrow too.

Any other advice that I can use tomorrow would be nice.

[jedi03]

compression test?

[Shirohige]

compression test?

Thanks, i'll keep that in mind.

edit; I've connected the intake air temp sensor to my ECU like people said, but: The red wire(signal) is connected to a blue/yellow wire on my ECU. Anyone know if this wire is the correct one?\

EDIT; WAIT DID I FUCK UP MY INJECTOR SETUP?
I put in 66% which should be good, but I see people use 0.2ms or 0.1 ms. I used 0.70ms. Please tell me this is the problem???

[cotbu]

What type of injectors? not all injectors have the same lag, even with the same cc. So dw555cc injectors?

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[Shirohige]

What type of injectors? not all injectors have the same lag, even with the same cc. So dw555cc injectors?

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Nismo 555cc injectors.

Edit: when i put my car on (not starting) my airtemp says 10-15 celcius, which is right. But when i start my car the airtemp says things like -8 and even -34...

[cotbu]

Can you lock the intake temp down in your software for troubleshooting? Disconnect etc.

Check sensor or wiring?

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[Shirohige]

Can you lock the intake temp down in your software for troubleshooting? Disconnect etc.

Check sensor or wiring?

Sent from my LG-H631 using Tapatalk
I fixed the air temp. It was indeed the wiring that was wrong, my ground wire to be specific. Now the air stays at 15 degrees and it doesn't do anything else.

Now during the selflearning after the first 10 minutes you have to turn on the ac which I dont have. So I just turned on the fans and the car did some reallyyyyyyy weird things, watch; https://www.youtube.com/watch?v=GZXVeiSi1y0

I turned it off after that. That shouldnt be happening right?

[Shirohige]

Ok, i reset the ecu again and tried to do the selflearning process again. Car stayed around 600-700 rpm and engine was shaking. There was a strong gasoline smell and my o2 sensor is staying at 0.0v. How much influence does the o2 sensor have on the idle process?

I am thinking of putting my 370cc injectors in the car and see what will happen. Any advice?? I am losing hope

edit; alright i might've find out about the o2 problem. here goes:

The redtop uses a E63 ECU with a skinny O2, no?
My redtop ran a E5 ecu with a fat O2. I think this is the problem since my power fc says the o2 has 0.0v.

Also, the O2 in my car now is from a 300zx. So I might have to buy a skinny o2 sensor, but if the o2 isnt really necessarry for idle-process then i wont buy it. I have a wideband in my car (not hooked up yet) which i will be using when I'll get it tuned. Anyone who can confirm this for me?

[bfellini]

O2 sensor feedback is used during closed loop fueling, including idle.
You'll need the correct sensor that the power Fc is expecting, unless there's a way to change the o2 cal table... double check your wiring as well [emoji106]


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[LayNLow]

Car sat for a year and a half? Can't believe no one has said to check the easy shit first. Drain your gas tank and put in a fresh tank of gas, its probably accumulated a ton of water by now. It will still shake for a bit I imagine, but it should smooth out after 5-15 mins.

[Shirohige]

Ye I'll change the sensor. I was using a multimeter and there was no voltage on the o2 cables. Found out there was a cable broken inside and I soldered it. Still no voltage, I think the harness isn't that good anymore.

There was fresh gas in it. The gas tank was almost empty when I put it in my garage. Anyway, I checked my spark plugs again and 2 of them were completely black. When I put them in a week ago they were good, but after a few times of starting the car they were black and wet from gasoline. I ordered new ones, gonna order a skinny o2 sensor and might look for a new harness.

I'll keep this thread updated.

[Frank_Jaeger]

There is a way to disable O2 feedback in the settings. It will make your car idle roughly but it's better than nothing if your O2 is stuck at 0V in closed loop.

I'm having a similar issue right now. I cleaned and tested my IACV, however I'm not sure if the coolant expansion part is working. I have no vac leaks.

Before I wasn't able to get my car to start at all until I pinched the intake hose on the IACV. Now I have a surging idle.

EDIT; WAIT DID I FUCK UP MY INJECTOR SETUP?
I put in 66% which should be good, but I see people use 0.2ms or 0.1 ms. I used 0.70ms. Please tell me this is the problem???
The injector latency needs to be: new injector latency - stock injector latency. So if new injectors are .77 and stock injectors are .58 then you would put .19.

[Shirohige]

^^^hope you get your running fast

Update: I hate my life now, but hey, my car works. After 400+$ further I found some issues. O2 didnt have a 12v output since the brown wire from the plug wasn't connected at all. I ordered a new engine harness, spark plugs and some other small stuff. Had to swap the plugs and everything. Car started, not idle. I didn't want to check my IACV yet so I thought; I'll check my injectors first.

Took them out, they were under gasoline. Both O-rings on 2 injectors. Switched them with my stock ones and the car worked perfectttttttttt. Well it idles perfect at least.

I thought I would go for a small drive, tested my brake and it was full with air, rip. So I thought, lets rev this b*tch up a bit since I missed the damn thing. Started revving, not above 2k rpm. When I hit 2000rpm the EAI sensor will turn on on the handcommander. Should be something with the emissions right?

[Shirohige]

update; So i tried running it without my TPS (which is automatic, my car is manual, i re-wired everything to make it work so thats not the problem). Anyway, idle with tps is around 870-900 rpm. Idle without TPS is around 1000-1100rpm, car still didnt rev past 2000rpm.

I used some carb cleaner on my Coldpipe and everything on that side of the engine, nothing weird happened, no leaks. Thought it was my map sensor so I used a T off the FPR but that wasn't the problem either. Saw a little coolant leak on the waterpump but nothing crazy, just a few drops.

The TPS is at 0.44v which should be good, but WOT it only goes to 0,56v? When the car is just "on" and I put my foot to see what voltage WOT will give it will go to 4.4 or something. But when starting the car it just won't get past 0,56v and it looks like the PFC just cuts the fuel for the engine.

I still don't know what the EAI sensor stands for? Should I just do the self learning process again? Can it be because of a faulty turbo or something?


Currently running: map sensor, stock injectors, gt28 s15 turbo

edit; ok after some intense FBI kinda research I found out that it isnt the EAI. I might look for a manual TPS and try that, not sure if I will. Might try my old ecu tomorrow and see what will happen.

[Shirohige]

Problem found; I tried doing the self-learn process, didn't work. TPS was fine, MAP sensor was fine, IAT was fine, ecu was fine, all wires were fine, wastegate was fine, no boost leaks. The goddamn problem was a tiny bit of air in my cooling system. The tiny bit came out and the car could suddenly rev to the max.

Hope this will help someone in the future.

[Shirohige]

Alright it actually didn't work a day after it worked... I have been messing with some things since then. This is what I did, and here is the solution (solution to not revving past 2k)

Changed TPS
Changed waterpump (leaking)
Changed radiator (leaking)
Changed thermostat (no hot air)
Changed engine harness (faulty wires, broken wires)
Been messing ever since.

Today someone told me to put the MAP sensor vacuum line on the T of the FPR. After that I resetted my power fc and it initialized again. After that it suddenly worked. If you ever face the same shit, try putting your MAP vacuum line on your FPR.

Good luck, hope it still works tomorrow.

[Shirohige]

Alrght, it didn't work. Can't go past 4.5k rpm now. Injectors go on 0.0% when it will reach 4.5k (around 4.5k atleast).

Anything I can try? Gonna look for leaky injectors tomorrow

[Packard93]

The first thing we should talk about is the engine’s idle circuit. I'm going to cover a fuel-injected engine here. Carbureted engine idle problems are handled differently. Since there are so many different configurations used depending on make and model, I'm only going to speak in general terms.

One of the prime suspects here is the idle air control valve, or IAC. This is an electronic motor that varies an opening in the intake that allows air to bypass the throttle plate when it's closed. The amount of air needed to maintain your idle is calculated by the computer. The computer dictates an IAC positioning based on inputs from the engine’s sensors, usually:

CRANKSHAFT SENSOR
Coolant temp
RPM
Air temp
MAP sensor readings
BARO sensor readings
O2 sensor readings when in closed loop
Air fuel sensors or AF sensors (similar to O2 sensors but a little fancier)
MAF sensors if equipped
TPS sensor
Load sensors such as the type for power steering pressure
AC clutch activation
Those are just the ones I can think of off the top of my head. I have a reason for listing all of these sensors. If you have a check engine light on for any for the above sensors, repair that fault first, then recheck for your idle problem.
I've had many people come to me and say that they've cleaned their IAC valve and still have an idle problem. Personally, I haven't had much luck cleaning IAC valves. I recommend replacement instead of cleaning if you find yours to be bad. I'm not saying don't clean them, because you might just get lucky, but if cleaning doesn't work, then you might end up having to replace it.

[Shirohige]

The first thing we should talk about is the engine’s idle circuit. I'm going to cover a fuel-injected engine here. Carbureted engine idle problems are handled differently. Since there are so many different configurations used depending on make and model, I'm only going to speak in general terms.

One of the prime suspects here is the idle air control valve, or IAC. This is an electronic motor that varies an opening in the intake that allows air to bypass the throttle plate when it's closed. The amount of air needed to maintain your idle is calculated by the computer. The computer dictates an IAC positioning based on inputs from the engine’s sensors, usually:

CRANKSHAFT SENSOR
Coolant temp
RPM
Air temp
MAP sensor readings
BARO sensor readings
O2 sensor readings when in closed loop
Air fuel sensors or AF sensors (similar to O2 sensors but a little fancier)
MAF sensors if equipped
TPS sensor
Load sensors such as the type for power steering pressure
AC clutch activation
Those are just the ones I can think of off the top of my head. I have a reason for listing all of these sensors. If you have a check engine light on for any for the above sensors, repair that fault first, then recheck for your idle problem.
I've had many people come to me and say that they've cleaned their IAC valve and still have an idle problem. Personally, I haven't had much luck cleaning IAC valves. I recommend replacement instead of cleaning if you find yours to be bad. I'm not saying don't clean them, because you might just get lucky, but if cleaning doesn't work, then you might end up having to replace it.

Idle is fine. Nothing crazy anymore. Can't change the topictitle sadly.

But only problem now is not revving past 5k. When I have to start my car i have to crank like 7 times for 10 seconds before it will actually start. Apexi Power FC gives a Starter error so im gonna check all my ground cables again

[Future240]

Idle is fine. Nothing crazy anymore. Can't change the topictitle sadly.


What would you like it changed to?

[S-Nation S13]

IACV should it be screwed all the way down while redoing the idle relearn process?

[Shirohige]

What would you like it changed to?
SR20DET not revving past 4.5k rpm

IACV should it be screwed all the way down while redoing the idle relearn process?
Wait I should do that????

[S-Nation S13]

SR20DET not revving past 4.5k rpm





Wait I should do that????



I read that it should be on another forum .. and then when you do all the steps you fine tune the idle by adjusting the screw.


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[mando240]

Idle is fine. Nothing crazy anymore. Can't change the topictitle sadly.

But only problem now is not revving past 5k. When I have to start my car i have to crank like 7 times for 10 seconds before it will actually start. Apexi Power FC gives a Starter error so im gonna check all my ground cables again

Hey, Bud. The same thing just happened to me a few months ago. My car would not turn on, and only turned on after 10 times at the starter; almost as if the car is flooded. Push starting worked everytime. Do you have a fp gauge? If it hits 0 when you turn off the car, then you may have a leaky injector, and it could possibly be your issue with the 5k rpm cut. Once I got that fixed, the car turned on right away.

[Shirohige]

Hey, Bud. The same thing just happened to me a few months ago. My car would not turn on, and only turned on after 10 times at the starter; almost as if the car is flooded. Push starting worked everytime. Do you have a fp gauge? If it hits 0 when you turn off the car, then you may have a leaky injector, and it could possibly be your issue with the 5k rpm cut. Once I got that fixed, the car turned on right away.

Don't have a FP gauge :(. But someone on the forum said that you can check leaky injectors when you turn your key in the ON position? Might do that.

@S-Nation S13
Alright, im gonna do a bit of research on that, thanks.

[mando240]

Don't have a FP gauge :(. But someone on the forum said that you can check leaky injectors when you turn your key in the ON position? Might do that.

@S-Nation S13
Alright, im gonna do a bit of research on that, thanks.

If it's leaking internally then you will not know unless you remove the injectors. Good luck, hopefully you fix it soon!

[S-Nation S13]

If it's leaking internally then you will not know unless you remove the injectors. Good luck, hopefully you fix it soon!

to check for leaky or busted o-rings on injectors i usually just pull the spark plugs out before i crank the car. Ill let the car sit over night, and then pull the plugs in the morning. smell the spark plug. we all know how gasoline smells like.

[Shirohige]

Didnt have much time to do stuff because my exams.. Anyway here is the car doing weird while idle.

https://www.youtube.com/watch?v=7FiQg94D-Uk&feature=youtu.be

What u guys think? Leak?

[Shirohige]

Alright, starter signal wire (orange wire, dash plug) is only getting 8-9 volts when cranking the car. What should I do?

[Shirohige]

Alright, did a boostleak test today. No leaks. Still not revving past 4/4.5k. The starting problem is most likely because of the orange wire. It fired up right away 2 days ago when it was pretty hot.

Haven't done anything to the orange wire since that is not my main problem now. Wanna get this car fixed already. Any ideas what it can be? Could it be a faulty power fc? I just dont wan't to think about the powerfc being faulty. Costs me so much money lol

[Shirohige]

Thought that it might be my power fc that was bad. Today I extended the maf wiring and put on my old ecu. Car doesn't start at all. Only cranks and that's it.

[S-Nation S13]

Thought that it might be my power fc that was bad. Today I extended the maf wiring and put on my old ecu. Car doesn't start at all. Only cranks and that's it.



You extended the wires , food for thought did you use the right gauge wire for all the wires. Number one issues with extending the wires on the maf is that people use the wrong gauge wire, which in turn messes up the maf.


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[Shirohige]

You extended the wires , food for thought did you use the right gauge wire for all the wires. Number one issues with extending the wires on the maf is that people use the wrong gauge wire, which in turn messes up the maf.


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I had an old harness laying around and the maf wires were extended too. I used those wires on my new harness. Should be okay I guess. But even with bad wiring, the car should start up but run like crap right?

[Shirohige]

Alright, found out that with the stock ECU the injectors aren't firing for some reason. Measured the voltage and it was around 6 and slowly dropping to 0.02.

Hooked up my power fc and here comes the weird part; voltage on injectors were 60volts and also slowly dropping How the hell can it be 60 volts? tf is this?

Also, im using a JDM harness. That shouldn't matter i guess? Just clarifying

[Shirohige]

Solution found. I'll update my first post in a few minutes.