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My Gtr Doesnt Wanna Go...

neshgtr

By neshgtr,
in Engines & Forced Induction

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neshgtr Community Regular

neshgtr

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hi guys i have few problems with my r32 at the moment..

upon cold start my oil pressure climbs to 3/4 mark.. is that safe as i dont drive it until it warms up.. i baby it around until it drops to 1/4 mark on idle and roughly 1/2 way on load.. i use motul 10/40 semi synthetic but open to suggestions on other more appropriate oil as i have 2 change oil shortly

also wen i drive after warming up a little.. the car drives oddly.. i could have my revs up above 3k and it will not be responsive at all (30-40kms - let alone boosting).. it feels like its being held back and towing something instead and all of sudden it will feel like pressure is relieved and it drives as it should.. could this be something to do with spark plugs / afms / coil packs coz only thing changed previously was spark plugs to copper (BCPR7ES)..

it is also backfiring between 1st/2nd gear changes frequently and i have been told by my cuzn that my exhaust(cat) sensor wire was cut and not connected by the previous workshop when they changed my cat-back zorst.. will this cause the car to run rich and cause backfiring.. car was furthermore epa'd recently and i need to take it to test centre for clearance.. im sure that will fail wit the car's current state.. please help/advice.. much appreciated

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SLIPPERY Experienced

SLIPPERY

Posted
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your 'cuzn's' a twit. The sensor is only there to tell you if the cat temperature is getting too hot :P

Theres been a couple of threads in the last fortnight in this section in regards to the cold start dilemma you also share. At present no one has a definitive answer. Have a look at the coolant temp. sensor and you should be on the right track because the value may be stuck to hot, thus making your cold start mixtures lean which causes the hopping around and reluctance to rev.

The backfiring between gear changes would be excess fuel combusting in the HOT exhaust. The stock ecu likes to run very rich for safety and unfortunately this makes for rubbish top end and fuel economy.

neshgtr Community Regular

neshgtr

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umm.. if i reset the ecu (hks kansai chipped) will it make any difference in regards to the car running rich.. will this have any effect on how loud the car is (zorst).. i also have a feeling my cat might have gone as i never used to get build of zorst carbon on the rear bumper.. how can i be sure??? i check out the coolant temp sensor tmrw.. also if my spark plugs are incorrect/fouled will this result im in my car lacking power initially.. thanks

ike Collaborator

ike

Posted
Posted (edited)
umm.. if i reset the ecu (hks kansai chipped) will it make any difference in regards to the car running rich.. will this have any effect on how loud the car is (zorst).. i also have a feeling my cat might have gone as i never used to get build of zorst carbon on the rear bumper.. how can i be sure??? i check out the coolant temp sensor tmrw.. also if my spark plugs are incorrect/fouled will this result im in my car lacking power initially.. thanks

Just a thought regarding the disconnected exhaust temp probe . When a catalyst becomes to hot it breaks down so to stop this happening the ecu dumps extra fuel to cool it down and increase its lifespan

The ecu gets its input from this probe. If this probe is disconnected The ecu will think it is full scale hot all the time and dump fuel ( richen it up) resulting in less power.Get it reconnected .

All modern cars have this .

Save the catalyst f*#k the earth thats capitalism for you.

hope this helps

Ike

Edited by ike
SLIPPERY Experienced

SLIPPERY

Posted
Posted

Dont these Jap modified stock ecus just chuck in more fuel and a bit more timing? Thus making your problems worse?

It also wouldnt hurt to change your plugs as they may be misfiring a little and perhaps causing unburnt fuel, popping and the black soot on the back of the car

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