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240Lover770
05-05-2014, 07:41 PM
hey everyone. been around the forum for a while but this is my first tech question.
i recently got my car back and have been putting break in miles on the car. did an oil change at 500 miles and now im currently on 1700miles. yesterday the oil pressure light creeped on while at idle then bevame constant while idle. once i accelerated or got it passed 1000rpm the light went out. i did a search and found a few pointers. right now im at work but once im home im gonna add a little oil to see if it does anything. engine specs are stock head with ras acl bearings 9:0:1 cp pistons manley rods cosworth head gasket 2871r turbo and power fc Djett for engine management with turbo running off the stock wastegate. i want to test every possible measure before i call it the oil pump and have to drop the pans and down the car. any help is welcomed. flamming too i guess. thanks.

cotbu
05-05-2014, 08:08 PM
The oil pressure switch on our cars are garbage, but if they are working correctly, you got problems!

first check to make sure the oil pressure switch wiring is not grounding out, that's a pretty common problem along with the brake light switch staying on too. They get worn and touch something, might flicker might stay solid.

The switch is activated at about 7psi don't quote me, but if the oil is old/contaminated and idle is strong when the light is activated you could have done damage, now if the engine bogged down and was really low in rpm you're probably good for obvious reasons.

adding oil shouldn't effect the pressure unless you where really low on oil, it a pressure switch not an oil level indicator.
Consensus is to run an aftermarket oil pressure gauge. 90psi+ at start up, 20psi+ at idle, oil at operating temp\hot 18-17psi min, 10psi being the limit for idling. my rules!

The fsm has an rpm based pressure reference.

240Lover770
05-05-2014, 08:17 PM
ok. i dont have a pressure guage and unfortunately the power fc doesnt even monitor that. ill have to get under there and mess around with the switch. should i pull it out and put it back in? and yes the car has bouncy idle right now and light only comes on at idle. but as soon as i give it gas and rpms are above 1000 it goes off. like i said it "creeped" on when i first saw it then started to stay solid only at idle.

240Lover770
05-05-2014, 09:05 PM
Update: put a little oil in and reached down to touch the oil pressure sensor. Jiggled the wire and put the rubber boot back on(was off when I touched it) turned the car on and no light. Let it warm up to op temp and still no light. So I took it around the block once. Still no light. So I'm happy but still a little on easy about it. What would make it go off like that? Intermittent pump or switch? Engine temp? Car was running a little hot when it lit up(100c). Could that be it? Or just a faulty switch or faulty pump or both? Kinda weird.

cotbu
05-05-2014, 09:30 PM
faulty switch or wiring and or pump
the oil could have been thinned because of age or temp.

240Lover770
05-05-2014, 09:52 PM
Thanks for the help man. I'm gonna monitor it and post if something else goes wrong again because that's kinda weird

240Lover770
05-06-2014, 03:14 PM
Did an oil change with castoroil 10w40 conventional this morning and drove about 30 or 40 miles with no problem. Previous oil was 5w30 conventional changed when the motor had about 600 miles. Put the 10w40 in at 1717. No issues yet

fliprayzin240sx
05-06-2014, 10:00 PM
Personal preference, when its hot, I've always ran 15w50. 10w40 seems to thin out on SRs and give you shitty oil pressure during the summers.

240Lover770
05-07-2014, 11:41 AM
Well I am in Hawaii so I'll take that into consideration on next oil change. Shitty part is I don't have a oil pressure guage right now.