engine cut / upgrade list for completely stock 94 r33 rb25

[Chadbugden]

I've got a problem with my car every time it gets hot the oil pressure seems to drop down to 2 bar @ 4000 I've only.had the car a year so bare with me I'm new to the skyline and also the battery lugs could be causing this cut out and could these problems be related to one. Thing, also looking for more ponys cheapest way to run more power on a stock tune. Hyperlinks would be appreciated, thanks guys

[Skym]

If cutting out, oilpressure is dropping, check oilpressure vs factory figures in engine manual. It could be a failing oilpump, excessive bearing wear, wrong type of oil causing excessive engine noise that ECU is picking up on.

Translated engine manual -

http://www.jpnz.co.nz/afawcs0131170/CATID=24/SUBID=273/page=1/products.html

If wrong type of oil, change the oil to a 5w40 which is good to around 120 degrees C. Stock oil (5w30) is good to around 100 degrees C. Buy a oiltemp gauge, adaptor plate to place under oilfilter, where the sensor for oiltemp gauge goes. Also check your cooling system, as the heat from coolant can be transferred to the oil via the stock coolant to oil oilcooler that's located just behind oilfilter. ECU could be reacting to the higher coolant temps.

Mods to gain the most hp without ECU tune and dyno results -

Full exhaust -

http://www.youtube.com/watch?v=qoGctn5o2Kg

Intercooler -

http://www.youtube.com/watch?v=t6FJUmChzgQ

40kw x 1.341 = 53.64hp

A RB25DET engine is sensitive to those sort of mods (high compression engine) and you really need a ECU tune after the exhaust mod to make sure engine doesn't knock. ECU tune wise there's up to +38hp available with aggressive tune, around +20hp with a safe tune.

If can't afford it right now, wait off until you can get a ECU tune with those mods installed. It's better to wait than lose a engine due to knock.

[99_SI]

engine cut / upgrade list for completely stock 94 r33 rb25

You oil pressure sender is failing, assuming the mileage is not high, otherwise Skym is right...pump is on the way out. Get your mechanic to physically test oil pressure as stated in the SM. Mine was dropping to almost 0 on the highway at 3K...300zx TT is a cross references part for oil sender for rb25. Paid less than $100 for new one off eBay. As far as mods go I have de cat, 3" turbo back exhaust with divoced dump pipe, hks mushroom and greddy fmic...no tune yet...and since you just got the car I would start with doing basic maintenance first...diff oil , coolant, tstat, water pump/t belt, brake fluid ...check your plugs. As far as battery goes seen some aussies having issues with melting positive cable at the fuse box. Check that you have proper connection at both battery and fuse box as well as the twostudded ground at the body. Address any issues as required. Battery lugs will not cause poor oil pressure. Btw this is wrong car to put cheap parts on...learned that the hard way...


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[Skym]

That oil pressure sensor / sender problem is common. I assumed he was reading from an aftermarket oil pressure gauge going by the bar measurement.

[Chadbugden]

I read the codes.and it came up 12, maf so I got a new one coming in Canada so hope won't be too long could that cause gas in the oil and drop the pressure?

[Skym]

Sounds like the ECU was picking up on knock, which is what I was thinking, but didn't know the cause of the knock. A faulty MAF being the cause makes sense. Stock R33 ECU can pull ignition timing to 0 on knock ignition map in an attempt to stop engine accelerating in the midrange (around 3500rpm+), so that could be the cause of the drop in oil pressure. The faulty MAF would explain the engine knocking, ECU switching to knock maps (also known as low octane maps for when engine runs on low octane gas).

[Chadbugden]

So I got the new.maf but I'm still running low oil pressure.when warmed.up and don't know.where to go from here?

[Skym]

If using the stock oil pressure gauge, replace the sensor. It gets clogged over time.

[Chadbugden]

Is there anyway to clean it? Long.wait.in nl for parts

[Chadbugden]

ok so I took off.the sender and manually checked the o/p with our homemade "precision instrument" (stock car op gauge and help from nappa and a soldering gun) showed 25 psi at idle everything seemed.fine blew.a.bit of air into the sender and stock gauge seems to be working fine however I did notice a significant loss of power and I believe it's my turbo I rebuilt it out of two with 140k I bought used so no big deal just wondering if that sender runs to the ecu can it trigger a "safe mode" she doesnt.pull until 6000 any advice?

[Skym]

It usually is straight from the sender to gauge.

Sounds like stock ECU is pulling the ignition timing, if engine accelerates normally from 6000rpm+.

The reason why could be anything, faulty FPR, fuelpump, etc. Turbo could be a possibility, but usually would hear a whistling sound from turbo (compressor or exhaust wheel touching housing).

[Chadbugden]

whistling sound, check lol i think she gawnnn.

[Skym]

First, check for intake leaks (loose intake hose clamps), then if still there, pull intake piping off front of turbo and see if the compressor wheel touches housing.

[future_R34]

Hope it works out! Gettin my r33 hopefully by the end of the month. Have to meet up sometime. Only 45 mins away in Appleton