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hi all... my rb20 cefiro is running like a true dog...

i put in a r34 side mount cooler and ever since then my car has been poping on near every gear change and if i go to gun it.. it iwll start boosting fine and its like as soon as it hits full boost it backs the timing off so far that the engine barrely revs..

and when i let the car idle it will sit at 1000rpm for say 10 seconds then drop to normal 650rpm idle.. then all of a sudden bounce down to like 200rpm then shoot up to 1200rpm then back down.. constantlly..

i have pulled off lines to the aac valve and cleaned inside with throttle body cleaner but that did nothing..

i have pulled every elec connector and cleaned it with contact cleaner.. i have pulled out cas and cleaned it all...

it has starting doing it out of the blue..

i thought it could have been leaking air once it hits boost so today i pulled cooler out and put it back in making sure it could not possibly be leaking air from any where....

im so f**ked off... just bought locker and dont want to bother putting it in till this shit is working again..

is what i have described tell tale signs of any sensors being f**ked..????

please somone help a brother out..

cheers in advance

Pressure test your intake system. Your problems sound like a boost leak. Block the pipe on the intercooler in-side from the turbo, and use an air compressor to inflate your intake to about 5psi. Put the air in via the vacuum line connection to your fuel pressure regulator. You will hear the leaks.

Clean your maf sensor too.

is their posible to have to much presure on the fuel presure regulator.. blow out anything???

what is causing idle to bounce irratically then??

it does feel like massive boost leak cause it spools real loud... but goes no where..

sucks

You wont damage anything at 15psi, but 5psi will be fine. This is done with the ignition off (engine not running). 5PSI is plenty to be able to hear the leak. If you dont have access to an air compressor with an air pressure regulator, use a co2 or argon welder gas bottle with a regulator set to 5psi instead.

Despite having great quality silicon hose and good bolt on hose clamps i still found leaks when i pressure tested my car.

Other non obvious area's leaks can happen is the clutch booster and brake booster, and the one way valves can fail that feed them.

alright sounds easy enough to test.

what about the wild idle... i would thoughtt that even with a big leak it woudl stilll atleast hold idle steadyish with the aac valve???

Eliminate the leaks first. You might well find a leak on the vacuum side of the throttle body... there's the idle problem. If its sucking air from somewhere thats bypassing the MAF sensor the engine cant fuel the engine properly. Also the IAC settings in the ecu wont know how to make it idle stably as the maf readings arent consistent for the engine speed.

Tried pressurising? So you pumped it up to 5lb, watched your boost gauge. Stopped pumping it up and it held pressure for quite some time?

Maf sensor. Get some CO contact cleaner and spray the sensor wire and clean out the inside of the sensor.

i dont run a boost gauge and just used a compressor on the presure reg line... held hand tight as can be over afm... couldnt hear a sound or feel a leak...

i havealready used throttle body cleaner on the afm..

cuz my motor is a cefiro rb20 didnt come with a factory bov so gets a bit of oil mist over afm occasionlly..

cleaned that its like new now.. still no change

well no im not positive. i geus i should try that.. i rekon first thing tomoro im goona chuck my stock cooler back in see if that changes any thing..

its the r34 smic as aposed to the stocko smic.... its all bolt up...

used the same joiners and same hose clammps...

cant imagine i split any but i have spares so i will try swapping coolers back over..

not somthing to do on a dissordelly friday night..

haha

cheers

okay iv just swapped my stock cooler back in and it has not changed a thing... i made sure eveyr hose clamp was tight as tight..

and i presurized it again.. but stilll nothing....

i hate not being able to enjoy my car..

im goona put my r34 smic back in and just take it to a work shop.. make it their problem to fix...

iv had enough of f**king around with it...

cheers for your help guys!!

:D

catchya

The idle dropping and going to 1200rpm is what my R32 was doing when the AFM joints were cracked.

I know you have cleaned the AFM but you need to look at the soldering joints in the square box thing on top of the hot wire element.

search the forums for "AFM+SOLDER" and you should get a few threads.

some have pics and so on.

solved my problem.

hey thats a great idea man..

i have pulled off the afm cover and the solders seem fine. im waiting on a solering iron form a mate so i will touch up the solders any ways..

will let you know how i go..

i called mechanics in my area.. their all busy for the next week or so..

sucks.

i resoldered all the connections in afm.. did not change a thing...

i hgave moved the cam angle sensor as far as it will go right... power and drive ability ha picked up a tiny bit.. still wont hold steady idle...

it doesnt seem right that the timing is that far advanced...

sorry how exactly do i do that... all that is on the ecu is a adjustable know.. which how it was, was as far anti clock wise as possible.. not sure if i should play with that :S..

let me know yo.. cheers

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