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Hey guys, as the title says....

I got my R33 Gtst back today from Unigroup, I was having the following installed and tuned....

Hypergear ATR43G3 .82 turbo

Nismo 555cc injectors

Z32 AFM

Powerfc

Yavuz explained to me the car had issues on the dyno, the car made a laggy 230rwkw and said he couldn't go on further on the dyno because of the issues listed below....

known issues:

-Engine running 85-90 deg C, gets warmer after power runs leading to loss of power, Cooling system marginal. (aftermarket radiator?)

-Crank angle sensor, RPM signal noisy, unstable after 5500rpm (no idea about CAS)

-Problems with Idle Air Control vavle and idle stability. Some hunting after startup especially when cold, Fuel mixtures and timing all ok. (IAC clean will fix this?)

-Car randomly drops down to 5 cylinders (2 occassions, after 30 seconds it fired back up) ( taking a guess, is it the ignition module or the CAS? or both?)

My question is, does my car sound mechanically healthy? Because these issues sound like all electrical faults.. but im not sure

he has advised me to take it easy on the car and can still use it as a daily just till i bring it back to him, but im worried about driving it all now.. Can i still drive it? it drives fine, smooth and all. Only thing i can pick is the idle, it sounds like the car is going to die.

Any help is appreciated. Thanks

Aleck.

Edited by Aleckr33
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he is very smart so i would believe wat he says.

but where does your idle sit at normally?

what cooling system mods do you have? has it ever had a cooling system flush etc?

i would try upping the idle a little in the power fc hand controller in settings REV/Idle the select the idle should be at around 850ish, if it is try upping it to 1000 and see how that goes.

it is common for the ignitor to play up when it gets hot, if you can get one from a mates car to borrow for a day or so so you can see if it happens, but if it doesnt happen to you then its going to be near impossible to diagnose.

Few things that I'm aware of when moding my test car. Hope those information helps:

known issues:

-Engine running 85-90 deg C, gets warmer after power runs leading to loss of power, Cooling system marginal. (aftermarket radiator?)

Check for rust. Some cases the radiator has a build up of rust that affects cooling efficiency, flush it out of that is the case. Also RB25det runs of a clutch fan. When the clutch wears this issues also happens.

-Crank angle sensor, RPM signal noisy, unstable after 5500rpm (no idea about CAS)

Sounds like the bearing in inside of it.

-Problems with Idle Air Control vavle and idle stability. Some hunting after startup especially when cold, Fuel mixtures and timing

all ok. (IAC clean will fix this?)

There's a small motor open and shuts the valve, normally a few spray of WD40 would fix it. Else get a new valve.

-Car randomly drops down to 5 cylinders (2 occassions, after 30 seconds it fired back up) ( taking a guess, is it the ignition module or the CAS? or both?)

Could be Coil pack miss-fire, spark plug flooded, faulty injectors, or coil ignition unit.

if the car runs like a crap then I wouldn't drive it. normally tunners would retard of timing and make it rich. So fix every thing up get it fully tuned before driving it around.

Also did you end up making a 4 inch metal intake pipe with a free flow exhaust?

Thanks for reply tao, ill look into this.

I got a hard 3 inch pipe made up with a 4 to 3 inch reducer from turbo.

Im running spiltfires and brand new nismo injectors. So makes me think it must be the ignitor.

That CAS problem could be belt flop. It seems to happen to a few guys here on this forum but you're the first at such a low power level to have that issue.

Yavuz knows his stuff, why not ask him what to do to fix it up?

Dont install a Nismo thermo - that won't fix the issue.

The issue will be the radiator and cooling system needs a GOOD flush.

After you have flushed it a few times very intensively, distilled water + coolant. Don't use tap water

It should be fine then.

A low temp thermostat won't cool a hot motor. When the thermostat is closed little cooling takes place. When it is open it makes no difference what kind of thermostat it is. Apparently the purpose of a low temp thermostat is to promote more even warming up of the engine. It won't solve any overheating problems but it will get your heater working more quickly in winter.

Alex, what have you changed since your car last ran well? I remember your car ran fine when you took me in it last.

I would say the major component you have changed is the ECU. The ECU is in control of all the components and the readings that would be telling Yavuz that its wrong would be coming from the ECU (RPM signal etc).

I have a strong feeling that your ECU could be a dud. Perhaps water damaged? It was 2nd hand from memory..

Ah.... Thanks for that. So has to be coilpack :( damn i only bought these few months back (2nd hand)

The coilpacks could be fine - IMO you should swap with a known good set and try them before buying a new set. Splitfires have a good reputation. Other things to look at are the coilpack wiring, injectors and injector wiring (if your injectors are low impedance there's a resistor pack in the circuit).

Having said that, intermittent problems are often coilpacks...

If it were me i'd get the other three issues sorted first as they should be easier to sort out, then see if the drop out is still there and if so move onto troubleshooting that.

PM me if you want some help

Flush the coolant system a few times should fix the overheating.

With the AAC take it off and soak it in petrol and then clean it with compressed air, they manage to get an amazing amount of oil and crap gummed up inside them over 20 years.

Thanks for reply guys.

Iv flushed the radiator today and new coolant put in. Oil and oil filter changed also. Went for a 20mins drive and temperature has dropped about 5 deg.

Iv always had the idle hunting problem since iv bought the car but since i got the car back its happening a lot more often, especially on cold start ups.

Iv noticed my power fc is reading the ign timing of 15 and sometimes will fall back to 14 then up to 16. Is this normal?? At the same time the car doesnt sound likes its idling smoothly, sounds like its missing.

Anyways, got the car going back feb 14th. Till then it wont be driven much.. Or at all.

Edited by Aleckr33

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