PA MATT

iTrader: (1)

Today, it was about 75 here in PA. I came home from school and I noticed my oil pressure was very low. about 30 psi at 2500 rpm's, 37 psi at 3500 rpm's. What could cause this? Obviously low oil could. I just changed it with Castrol GTX 10w-30 and a Fram filter. Could the filter be "faulty" and causing this? Normally, I see about 50 psi at 3000 rpm's and I've heard you should see 60 psi at 3000 rpm's. When I did arrive home (2 hour drive) I let my car idle for a minute and my oil pressure was on the low side between 0 and 10 (guesstimate about 5psi).
It's a stock D16Z6 with Greddy 15g and 134,XXX on it. Do you think this could be a bearing problem or an oil pump problem? Faulty pressure relief valve? Any help would be great, thanks!

y7turbo

could be the oil pump or the pick up tube screen could be clogged with ****. i would not drive it to much anymore with that low oil pressure. it should be alot higher.

mine is 20 at idle and 80psi above 3000rpm.

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by y7turbo &raquo;</TD></TR><TR><TD CLASS="quote">could be the oil pump or the pick up tube screen could be clogged with ****. i would not drive it to much anymore with that low oil pressure. it should be alot higher.

mine is 20 at idle and 80psi above 3000rpm. </TD></TR></TABLE>

mine is also 20 at idle and 80 psi above 3k. i have 126k miles on the engine and a week or so on my greddy 18g.

SilCiv2K

main causes for low oil pressure is worn main/rod bearings , worn crank journals, partially stuck open pressure relief valve in your oil pump. good luck. dont forget d16 shortblocks are dirt cheap.

do not drive the car on low oil pressure as it could begin damaging your valvetrain.

PA MATT

iTrader: (1)

thanks guys. I started the car up after lettin it cool down and oil pressure was at about 30 psi idling. It was warm, but not hot. It's around 80 when it's cold and i first start it, but never when warm and over 3k. Maybe at redline, but not 3k. How can I diagnose the cause of this problem? I don't want to rebuild the motor if it's only the oil pump. Thanks again for the help

PA MATT

iTrader: (1)

just another question....in my tee, the oil feed line for turbo is fed first and then the gauge feed behind that. Could the length of the gauge line or the location(after the turbo feed) cause me to get lower readings? Is there anywheres else on the engine that I can pick up an oil pressure reading temporarily?

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PA MATT &raquo;</TD></TR><TR><TD CLASS="quote">just another question....in my tee, the oil feed line for turbo is fed first and then the gauge feed behind that. Could the length of the gauge line or the location(after the turbo feed) cause me to get lower readings? Is there anywheres else on the engine that I can pick up an oil pressure reading temporarily?</TD></TR></TABLE>

It shouldnt, because i have a 3 way tee from Tuner Toys...the two 1/4 npt on the side feed both the turbo and my oil pressure sender, then the end of it is where the dummy light factory sender goes. my oil pressure reads the same as it did before i even had the turbo line in (when i just had a plug and only the oil pressure sender line connected).

PA MATT

iTrader: (1)

okay...I was considering just buyin a sunpro oil pressure gauge for 15 bucks from autozone and plugging it in near the vtec solenoid to see what kind of readings im getting with another gauge. I don't know as though it's worth the trouble though.

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PA MATT &raquo;</TD></TR><TR><TD CLASS="quote">okay...I was considering just buyin a sunpro oil pressure gauge for 15 bucks from autozone and plugging it in near the vtec solenoid to see what kind of readings im getting with another gauge. I don't know as though it's worth the trouble though.</TD></TR></TABLE>

for the extra 15 bucks to spend versus knowing that something is severely hurting your oil pressure, i think its worth a try.

PA MATT

iTrader: (1)

where exactly is this "hex plug" that's sposda be near the vtec solenoid? I couldn't find anything anywhere

Pay2play killa

if the bearings in that 15g are shot then its like spinning a rod bearing; you loose oil pressure due to loose clearancse. I had that problem and did spin a bearing due to low oil pressure because the turbo sucked without the turtile my idle oil pressure was over 30psi even after a 30 mile drive; w/ the turbo it was MAYBE 10 at idle when the motor was hot.

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Pay2play killa &raquo;</TD></TR><TR><TD CLASS="quote">if the bearings in that 15g are shot then its like spinning a rod bearing; you loose oil pressure due to loose clearancse. I had that problem and did spin a bearing due to low oil pressure because the turbo sucked without the turtile my idle oil pressure was over 30psi even after a 30 mile drive; w/ the turbo it was MAYBE 10 at idle when the motor was hot.</TD></TR></TABLE>

even if i'm referencing the oil pressure at the back of the block, will my gauge still reflect a shot bearing in my turbo?

PA MATT

iTrader: (1)

without tearing the turbo apart, can i diagnose bad bearings in the turbo? I know it has quite a few miles on it...probably 15-20k

coneheadsracing

aren't all turbos just gravity return? So, how would a bad bearing cause low oil pressure. There isn't any pressure returning to your pan. You probably had low oil pressure because you had already spun the bearing in your motor, and then it finally went.

For the original poster, wheres your tee at for your pressure guage. I have mine tee'd right out of the block, one line up to the firewall for my guage, and the other to the turbo. Otherwise, for a quick check, just put your guage into your block, just don't drive the car, you could also have a friend hold the turbo intake wheel just to be safe so it doesn't start to spin, don't think it would though.

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PA MATT &raquo;</TD></TR><TR><TD CLASS="quote">without tearing the turbo apart, can i diagnose bad bearings in the turbo? I know it has quite a few miles on it...probably 15-20k</TD></TR></TABLE>

good question. i know that previous owner of my turbo did some pretty stupid things with it since he was in such a hurry to get the install done, for one, he didnt have a boost gauge, and best of all his wastegate was all fuxored and didnt want to open when i got the turbo. its no wonder he blew his engine. he went back to his "NA is best" world.

so even though my turbo is relatively "low mileage", i too, want to know how to diagnose bad turbo bearings, while it is installed in the car.

coneheadsracing

bad bearings would result in a lot of shaft play.

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by coneheadsracing &raquo;</TD></TR><TR><TD CLASS="quote">bad bearings would result in a lot of shaft play.</TD></TR></TABLE>

well of course theres that.. enough shaft play and you can hear the blade(s) hitting the housing, but can u do check by any other means (funny oil pressure readings, erratic vacuum/boost)?

Pay2play killa

turbo wont affect vaccum.

**buy an inline ball vavle type restrictor and just give the engine oil pressure priority**
Meaning that if the turbo is going give it less oil. if its going it'll go no matter what; might as well protect your motor.
My 15g was going; it wasn't gone and i had no restrictor; then one time i blew a coupler so the turbo overspun hardcore and took out the bearings completely. The compressor wheel was chewing into the housing. soon after i spun a rod bearing due to low oil pressure. I didnt know any better.

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Pay2play killa &raquo;</TD></TR><TR><TD CLASS="quote">turbo wont affect vaccum.

**buy an inline ball vavle type restrictor and just give the engine oil pressure priority**
Meaning that if the turbo is going give it less oil. if its going it'll go no matter what; might as well protect your motor.
My 15g was going; it wasn't gone and i had no restrictor; then one time i blew a coupler so the turbo overspun hardcore and took out the bearings completely. The compressor wheel was chewing into the housing. soon after i spun a rod bearing due to low oil pressure. I didnt know any better.

</TD></TR></TABLE>

did u not have an oil pressure gauge?

PA MATT

iTrader: (1)

my turbo has virtually no shaft play, so I'm assuming the seals are good. Maybe a restrictor is something I should look into. I'm running a small tunertoys bradied feed line so idk if it's really neccesary. Also, I changed my oil. I have always run 10w-30 Valvoline Durablend in my car, but this time I went with Castrol GTX and a fram filter b/c it was on sale and I've heard good things about GTX. I changed back to Durablend with a Pure One filter. I now have 76psi at startup, 60psi at 3k when warm and 50 psi when hot. When I got back to school today, I had 12 psi at idle. I also looked in a Hayne's manual this weekend. It said that spec at idle is 10psi and at 3k rpms 50psi(warm engine), so i seem to be okay. Seems to just have been an issue of a different oil and possibly a faulty filter?

Pay2play killa

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spec R &raquo;</TD></TR><TR><TD CLASS="quote">did u not have an oil pressure gauge?</TD></TR></TABLE>

I did but for the longest i thought it read low :-/ now i know

Spec R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PA MATT &raquo;</TD></TR><TR><TD CLASS="quote">my turbo has virtually no shaft play, so I'm assuming the seals are good. Maybe a restrictor is something I should look into. I'm running a small tunertoys bradied feed line so idk if it's really neccesary. Also, I changed my oil. I have always run 10w-30 Valvoline Durablend in my car, but this time I went with Castrol GTX and a fram filter b/c it was on sale and I've heard good things about GTX. I changed back to Durablend with a Pure One filter. I now have 76psi at startup, 60psi at 3k when warm and 50 psi when hot. When I got back to school today, I had 12 psi at idle. I also looked in a Hayne's manual this weekend. It said that spec at idle is 10psi and at 3k rpms 50psi(warm engine), so i seem to be okay. Seems to just have been an issue of a different oil and possibly a faulty filter?</TD></TR></TABLE>

what were the readings with the castrol gtx?

PA MATT

iTrader: (1)

when hot (2 hour drive in 75 degree weather..first time it's been that warm this year) , it was about 5-7psi at idle(hard to tell b/c gauge reads 0 and then 10), about 25 psi at 2k, and about 35 psi at 3k. I had my mom's boyfriend(knowledgable diesel mechanic) look at my car this weekend. He said I was getting some blowby from the smell of the oil, but not a lot; and when i started the car/revved it he said it didn't sound like a bad bearing, but with low oil pressure I would develop one. The shitty Fram filter also could have had something to do with it. I had run the OEM s2k Toyo riko filter before hand, but was tired of paying so much for an oil change. I found the Pure one filter is supposed to be very good and only 5 bucks. So far, I've had good oil pressure. I really don't want to rebuild this for no reason.

SPOON_BeIgHtEeNsEe

sorry to jack ur thread but what psi reading should u be getting at idle (cold and warmd up)? normal driving around 3k fully warmd up? and WOT? d series motor too

Turbo-charged

pull your oil pan and inspect your rod bearings.