[help] Numerous Problems

[MUNDA]

Hey I tried to search and search tons but I couldnt come across anything... im sorry if this has been asked but anyways.

My car feels really slow i can hear turbo's spooling but theres no boost like no pull... my guages dont work any of them except for the RPM one every other one doesnt work. My HICAS light comes on when I brake and other times.

The stock boost gauge shows above 0 and it moves but feels slow doesnt show any vacuum.

I just got the car from japan and im trying to fix things.

I was thinking boost leak but im not sure

I ahve a 300zx and i know those very well but when look into the bay I dont see too many boost lines to check...

do these cars have the same ECU diagnostics as the 300zx? cause thats my next step but i was looking at some guidance or some tutorials to get things working

The car is a 1990 Skyline GTR Rb26

Edited March 27, 2009 by MUNDA

[The Dan]

Might help if you state what car you are referring to. I assume you are not talking about the 300zx having the problem because of the comment "do these cars have the same ECU diagnostics as the 300zx?"

Make and model, then people might be able to offer suggestions. I would recommend taking it to your preferred mechanic to have it resolved. With issues like that, I would say it will be difficult to E-fix

[MUNDA]

It's a 1990 Nissan Skyline GTR RB26

Edited March 27, 2009 by MUNDA

[The Dan]

Ok, I would start by topping up the power steering fluid. That should stop the HICAS light from coming on when you brake.

If not, then there is a more serious problem...unable to diagnose here easily.

Check all the fuses. The speedo works from a cable, all the rest work on electrical senders etc. Fuses are under the steering column to the side. Assuming you are in Aus yes?

If you can hear the turbos spooling then it is likely you are making boost. Put a manual gauge on it to determine what level.

If you are not, then look for leaks, if you are then do a compression test and suss out the condition of the rings etc.

Come back with results and we'll try some more stuff.

[The Dan]

there are also fuses in the engine bay. Check them also

[MUNDA]

Hello,

Thanks for the reply, i have already done a compression test on the engine, they are all in range. For the boost, the turbos are spinning, i have a aftermarket gauge that also does not move.

Do you think that having the speedo stuck at 0 could result in having no boost?

[The Dan]

Hello,

Thanks for the reply, i have already done a compression test on the engine, they are all in range. For the boost, the turbos are spinning, i have a aftermarket gauge that also does not move.

Do you think that having the speedo stuck at 0 could result in having no boost?

No, if the speedo is stuck at 0 then it may mean you are not moving, therfore you will get no boost.

That is the only relationship they will have.

HAve you checked all the vacuum line connections to the back of the plenum and the ones under the plenum? Have you checked all the fuses? Have you got a stuck open wastegate actuator or a soft actuator?

What tune is in it? factory ECU? have you checked or changed spark plugs? Checked or adjusted ignition timing?

The list goes on. Until someone can actually stand next to the thing and run some tests we can all stand around here making guesses.

What is the extent of you mechanical knowledge? If none, then take it to someone. If you want to learn, then be prepared for it to take a long long time to fix your car.

[MUNDA]

No, if the speedo is stuck at 0 then it may mean you are not moving, therfore you will get no boost.

That is the only relationship they will have.

HAve you checked all the vacuum line connections to the back of the plenum and the ones under the plenum? Have you checked all the fuses? Have you got a stuck open wastegate actuator or a soft actuator?

What tune is in it? factory ECU? have you checked or changed spark plugs? Checked or adjusted ignition timing?

The list goes on. Until someone can actually stand next to the thing and run some tests we can all stand around here making guesses.

What is the extent of you mechanical knowledge? If none, then take it to someone. If you want to learn, then be prepared for it to take a long long time to fix your car.

I have checked pretty much everything and i havent changed anything (yet)... i even took out the cluster and checked the speedo wire everything looks good...

its a factory tune. Pulled ECU codes got code 55

Another thing i noticed is when I turn my headlights on the whole cluster dies and my RPM gauge that worked turns off. When I turn the headlights off the RMP gauge (the only one that worked) works again. Also my gas gauge is past full too and it wont move from there as well my temp gauge in cluster is maxed as well only one that works is the RPM one.

I can do the work myself just need to know where to start haha im mechanically inclined and time isnt an issue for me

[SDEWY5]

sounds like ur ground is [email protected]'ll behave strangely like that if u have a bad ground connection on the clusters and tachos etc...

[MUNDA]

sounds like ur ground is [email protected]'ll behave strangely like that if u have a bad ground connection on the clusters and tachos etc...

But the lights screw it up so i dont know :S before the car came to me from japan it was fine (im in canada) theres videos showing it working and everything... I dont know what happened while coming here

Im wondering if any of this is related to me having no boost...

my guess is becuse the gauge is stuck at 0 im getting no boost, if i get the gauge to work then the boost problem will go away but im not sure

Edited March 27, 2009 by MUNDA

[The Dan]

But the lights screw it up so i dont know :S before the car came to me from japan it was fine (im in canada) theres videos showing it working and everything... I dont know what happened while coming here

Im wondering if any of this is related to me having no boost...

my guess is becuse the gauge is stuck at 0 im getting no boost, if i get the gauge to work then the boost problem will go away but im not sure

there is a bad earth somewhere.

good luck finding it.

Make sure the earth to the block and battery is clean and free of corrosion. Also make sure they are connected tight.

If you can't find any earth problem there, then look at the earths under the dash. You may find that the poor earth is draining your power also, as it will pull power away from you injectors when the ignition needs juice.

[MUNDA]

there is a bad earth somewhere.

good luck finding it.

Make sure the earth to the block and battery is clean and free of corrosion. Also make sure they are connected tight.

If you can't find any earth problem there, then look at the earths under the dash. You may find that the poor earth is draining your power also, as it will pull power away from you injectors when the ignition needs juice.

any places i should start or pretty much start from one side of the car and go on

where are the gauges earthed to?

[MUNDA]

Just an update,

I took off the front bumper and checked for leaks there, from what i can tell i see NO boost leaks. The only thng still not working is the cluster, i was told by a shop that the cluster and no boosting are not related in any way.

Could someone please clarify if the car could be thinking that the car is not moving, but in reality it is, and the wastegates are staying open?

I just need somewhere to start, ive poked around every corner of the car.

Thanks,

MUNDA

[The Dan]

Could someone please clarify if the car could be thinking that the car is not moving, but in reality it is, and the wastegates are staying open?

Geez I didn't think you would take that as a literal statement. I was pointing out the lack of relationship between your power drop and the cluster problem. Not that they have anything in common.

It is possible but unlikely.

I did suggest you look for a bad earth, check every single one. Start with the big main ones from the battery to the chassis rail and to the block (engine mount) and then check the one to the coil packs from the ECU, then check the one from the strut tower to the turbo, then pull your dash apart and look for problems there.

How did you check for the leaks in the piping? Did you just look and wriggle? If so, do it again properly. Undo each clamp and remove the pipe, clean the area that seals, put on a light smear of rubber grease or even a tiny bit of No3 and put them back on.

If you don't know the car, where the vac lines are, how to pull the dash apart, what an earth wire looks like, how to test for a bad earth or how to test for a boost leak with a proper tester, then take it to someone who knows and can help you.

Guessing will only get you so far. You might get lucky. I cannot see the car, therefore I cannot give you a difinitive answer but I thought at least a logical approach could be expected.

Attack one problem at a time, don't go looking for multiple problems all at once. You will only get confused and not know what's what. Fix your wiring first, it may effect your power level with a bad earth like I mentioned earlier. Then enjoy the car whilst knowing you actually have fuel in it and what rpm and speed you are doing.

[MUNDA]

ok so i have been busy with my car and i was checking all grounds so far so good. well i randomly decided to check ecu codes again and now im getting a

code 43 which is the throttle position sensor

does this have anything to do with me not boosting or my gauges not working??

and where should my first step be to fix this?

[xRHETTx]

Take it to an auto electrician, no offence but you have no hope of fixing your car yourself.

[MUNDA]

Take it to an auto electrician, no offence but you have no hope of fixing your car yourself.

Im in canada and nobody here takes the car... theres one place they have me booked for next week but tilll then i can try anything i can throw at it in hopes to fix it...

so im open to thoughts of where I should look to fix things...

im working on everything as i go i have checked all the main grounds and they are ok. Im not onto the ecu

we willl see how that goes but for now im curious about this code 43

[The Dan]

With the ignition on, check the output voltage (I think it's the middle wire of the 3 there). You should see between 0.4 and 0.6 volts with the throttle closed. Check to make sure you have 5V going in on one wire and make sure you have continuity back to the ECU on each one. Check the ECU earths also....if you have to, run a couple extra to be safe.

Pins 30, 38 and 48 correspond to TPS

30 is Sensor ground

38 is Signal

48 is voltage supply

With IGN on, 48 should see 5v, 38 should see 0.4 - 0.6v. Slowly open the throttle while testing this voltage to make sure you get a clean sweep all the way up to 4.1V.

[The Dan]

[MUNDA]

Alright guys, another somewhat good update. THE GAUGES ARE WORKING .

i did test it, but there is still no boost, you can distinctively hear the turbos spooling, there is a definite "wine" to them. Both my aftermarket and stock gauges are showing vacume, the aftermarket shows around 500mmHg of vacume on idle. When i gun it, the vacume lowers, ad boost boost gauges fall onto the 0 mark, hence no boost.

I took off the pipes and whatnot that are extended over the turbos, they are HKS turbos, and are mounted where the stock ones should be. I looked for any boost leaks.... i did soapy water test, i did the propane/butane test, but i cant seem to find anything.

I did the test for the TPS, all the voltages are in range. I tested all the ECU earths aswell, they are all rock solid and are all working properly.

Now, there are only the turbos left to work on, is there any way to check if the wastegates are open or closed while driving? IE, hook up a voltmeter to some sensor and look for a voltage change?

Oh, and a side note, i cchecked the exaust, there is no clogging, took a flashlight shined it into each pipe and looked, good exaust flow.

Hopefully now someone will be albo to help me narrow down this very, very annoying problem

Thanks guys,

MUNDA