Arthas

Hi all

After diagnosing my secondary turbo problems I've ended up replacing the CC solenoid (and some vacuum hoses) due to Ecu was reporting error code 45. (which causes limp mode). Also I had hooked up a boost gauge to my charge control valve chamber A just to confirm that my old solenoid wasn't working properly... so i let the gauge hooked up just to see how the new solenoid will operate...

So yesterday I've started the car and it ran smothly idle was fine everything perfect... but... My boost gauge (hoocked to CC valve) showed vacuum and that vaccum was being released slowly approaching 0 psi slowly all this with my car idling in the first min...

So thinking that maybe its normal I've decided to go for a ride...

surprise... can't boost my car... parked the car checked for error codes and again error code 45... with a new solenoid!!!

did a few koko and boost gauge always showed 0 psi "no vacuum" and sometimes just a few vacuum.. so moved under the hood to pull the codes and

in one of that KOKO process to get codes... after 10 secs of 1 KO... I've heard a loud "clack" like a suction sound ending with a clack... went fastly to check my boost gauge and there was... vacuum being released slowly...

all this makes me thinks that I've an electrical problem... but I don't know from where to start... Idk if i had a faulty ecu, faulty wiring... why im still getting this code after the replacing the solenoid!!!

Additional... Following dgessman guide to test solenoids.. I've tested the resistance of my old solenoid and it was fine 42! ohms and 40 ohms warmed on the oven... but as i couldnt test the vacuum or pressure throught the solenoid decided to get a new one... supossing that my old solenoid was leaking...

So please help me to find the problem... I've searched a lot on forum and on web... and there is no so much info about this error... or how to solve it

DaleClark

iTrader: (55)

Code 45 is going to be a pretty basic code. The ecu only knows if it sees the resistance of that solenoid. Most likely there's a wiring issue. Have you reset the ecu since you swapped in the new solenoid?

Dale

Arthas

hi dale

yes I've reseted the ecu twice..

when i was replacing the solenoid I've disconnected the the battery and it was disconnected for almost 1 week.. and yesterday I've reseted ecu disconecting and pressing the breack pedal for 40 secs

DaleClark

iTrader: (55)

If you still have the code either you have another bad solenoid, which is doubtful, or a wiring issue. The ecu is just looking at resistance, if it's out it throws a code. The ecu is VERY dumb about this. It doesn't know if the solenoid does what it's told or what, it just looks at resistance.

Start looking at your wiring. Also, all the 3 way solenoids are the same, you can swap it with another to make sure that solenoid is ok

Dale

Arthas

I've checked with a multimeter the resistance of the solenoids and all of them are fine... so i think its a wiring problem... or... could it be a faulty ecu????

Assuming its a wiring problem... how can i solve it... where the solenoid connector is going directly to ecu? what should i start looking for? only continuity?

I wanna cry...

DaleClark

iTrader: (55)

It could be the wire is frayed or shorting out somewhere between the plug and the ECU. Use a multimeter to test continuity from the plug to the ECU.

Could be the ECU, but that's unlikely.

Dale

iTrust

Hi, Arthas. Please write when solve your problem, i have the same
Even after rebuild i have no boost, i thought it was limp mode, but my omp is ok, so i shold looking for new problem
My car fd3s '00 AT

iTrust

Today i checked all my solenoids, last one was charge valve ) I heated it up in boiled water, checked resistance, it was about 80 and slowly went down till ~60. I have compressor, and under 15 psi i check this solenoid under water - it was leaked... haha, i found this bastard : )

Arthas

lucky you...

my problem stills there...

Today following the FSM i have checked the voltage at 4T ecu terminal to check what ecu is doing with the solenoid... I think that if there is a problem with wiring from egi relay to solenoid... voltage should be "0" always "0" but as i my solenoid was working intermitently I assume that solenoid has continuity with egi relay check below image to see where I've attached the multimeter




found that 1 of my starting components (idk what is) is acting intermitently.... you can hear in the video the random click click while key is at on... and on 1 of the clicks... voltage from ecu to solenoid jumped from 1.0 volts to almost 5 volts and came back...

As far as im understanding this system the ecu grounds the solenoids... and only measures the resistance... resistance provided by the solenoid...

following FSM with key On my solenoid should be showing no more than 1.0 volt and after 4500 rpm switch to battery voltage... but as you can see "when that think clicks randomly.. sometimes there is a spike in the voltage... like ecu is being affected by that clicks.. and operating solenoid on the wrong way...

here are the videos of the tests


Hear carefully the random clicks... and please help to identify which component is it

and


the behalf of the ecu with the KOKO you can see the voltage spike in this video

So please rotary specialists... can you give a hand with this? what do you think? wiring issue? fucked ecu?

P.S. on my last test with the car runing before touching the rast nest and etc... Solenoid was acting randomly... sometimes showing vacuum and switching to pressure pass 4500... and sometimes when passing 4500 not switching at all

P.s2 My ecu is an N3A7 18 881C

Narfle

iTrader: (16)

I'd swap out the ecu. Lots of people throw them away. Should be relatively cheap and easy.

Arthas

But how can i troubleshoot the ecu?

and whats the think that is clicking randomly... ????

Arthas

bumping for help!

Invoking to all mappers and ecu specialists...

rx7will

iTrader: (6)

Just in case anyone has this issue or issue with any solenoids under the intake manifold. You dont want to just remove the intake manifold because once you do that you can not verify if you actually fixed the problem. The FSM is wrong, they take the same approach, check connection, check power, check wire, and start replacing stuff. I just diag the same issue and my process will work with any of the solenoids.
1- remove computer connector and ohm test between pin 4T i think its a L/B light blue/black wire and a black/white wire. All the black white wires are shared, easiest to access is the wastegate control connector.batter and wastegate connector has to be disconnected.
2-a good solenoid ohm test around 40 ohms. A couple of ohms will not matter. Do this with the engine cold. If you are having an intermittent issue once you get the check engine light or issue, do the ohm test and compare it to the rest of the twin turbo solenoids. If you resistance is way off, in my case it was only 5 ohms. Resistance will go up with heat but we are only looking for the one that has the biggest difference.
3-If you resistance is off, next step is to remove the pin from the connector, plug in the connector and install and different pin in to the computer, run the wire to a known good solenoid, run the other end of that solenoid to battery, but do that after you put everything back. And with engine off key on, the code should go away if the computer is still good.
4-step 3 will tell you if you just have a wiring/solenoid issue or computer issue. In my case it needs a solenoid and a computer. Install new computer with the test solenoid and confirm the issue is gone. Then remove access solenoid, load test the signal wire to make sure its good. A simple ohm test wont be sufficient because a single strand of wire will still give you a good resistance test.
5-In my case the 5 ohm resistance shorted out the computer. Imagine if the solenoid is a light bulb, when the computer grounds it, it turns on. Now imagine that the bulb has a straight wire with becomes a straight path to power, which blows the computer driver. Connect one end of the wire to positive battery and tap the other end to ground, you get a spark. If you keep it there it then gets a lot worst.

This is the way i do most of my electrical diagnostic. This way i can confirm the fix before I really get into it. Obviously if the part was easily accessible and you had a spare, heck just plug the thing in and go from there. In my case, if someone just plugged in another computer it would have blown the new computer also. Then if they replace the solenoid they will still have the same issue because they just blew the new computer but now with a good solenoid and still have the same check engine light and same limp mode.

DaleClark

iTrader: (55)

Nice! The good thing is a hard short seems to be pretty uncommon. The main problem with the solenoids just seems to be them sticking or not holding pressure.

Dale