bad oil pump?

**ls1ws6ben** · 07-01-2011, 08:21 PM

so since ive had my car (6 months now) the stock oil pressure gauge has never went above about 5 lbs of pressure.. i havent got hard on my car at all.. done an exhaust and cut the cats out.. went and got a tune for it today.. after being at WOT after we stopped there was a not so nice noise.. the guy doing my tune said it sounds like i have an oil delivery problem. well he finished tuning the car. he said it pulls like an LS1 should but wasnt going to do any more hard runs in it til i pin pointed the problem.. from what i have seen and heard on youtube and some forums, seems i have a bad oil pump or atleast a bad o ring causing this problem.. can just the o ring be bad and the pump still good causing this issue of the oil delivery? i have priced the pump, screen and new o ring. under $200 for all.. havent checked on labor yet.. any way to test that pump? maybe put on a mechanical oil pressure gauge to test it? i just dont want to start buying parts i dont need and being a holiday weekend i wont be able to see a mechanic til tues.. so i turn to my fellow LS1 owners for advice..

**RyanJM** · 07-01-2011, 09:26 PM

Not sure if it's your pump but I can tell you install is a pita with it in the car. I have only installed one on a stand but when I had my cam done I had a slp high flow.oil pump and double roller chain installed and it looked to.be a time consuming install so I would say it isn't going to be cheap. I traded paintwork for engine work so not sure on the cost but I can tell you it looked like several hrs. If you are doing it upgrade to a better slp or melling pump and do a new timing chain while.it is apart.

**pajeff02** · 07-03-2011, 04:54 AM

Best thing to do is verify the oil pressure with a master pressure gauge. Unfortunately, this would involve pulling the intake at least twice, but that is really not all that difficult compared to playing with the oil pump. You could just have a bad sender and the noise could be something else entirely.

**NAVYGSE1** · 07-07-2011, 03:30 PM

Ben,
First, mucho kudos to your tuner for having the intesinal fortitude for stopping and making you pinpoint your issue before finishing it up. These days alot of other less scrupulous people/organizations would have taken your money and then double-tapped you when you came back after the repairs! (or worse new engine)
Second, put in the time to really diagnose the problem! The LS1's have MANY issues (both real and imagined/perceived, especially due to the all aluminum construction which amplifies engine noises). I am constantly "nervous" about the piston-slap issues that the '97-03's have been plauged with, but I am still investigating and I have been beating mine for near 59K miles now, not to mention this year I was stationed in Germany which has my "lil Angel" seeing speeds above 160mph several times a month! (of course it would be more if the wife wasn't with me) But I digress, back to your problem...
Since you have a low oil pressure gauge indication AND a noise, it most likely IS an oil delivery problem which is serious...find it and fix it ASAP as your engine lives (and dies) in its oils, or lack there of. Keep in mind the oil pressure gauge on the F-bodies is a compromise between the "Appearance" of a performance car and actual function, while the sender does give a low middle and high pressure signal to your dash gauge it cannot be relied upon if you are looking for actual oil pump output. If you do decide to install a mechanical gauge, be careful when working around or replacing the factory sender behind the intake as it is one of the cheeziest parts I have ever seen. It can be easily broken, I broke mine as I was pulling my intake for Knock Sensors replacement and the brake booster vac hose caught it and that was all she wrote!
Even though yours is a '98 (correct?) there was a TSB that covered numerous LS1's in ALL GM bodies for ticking noise(s) (years were '00-03 or '04 I believe) and it was due to the oil pump pick up tube o-ring getting cut during assembly thus allowing aeration of the oil, and this COULD be your issue. If you end up going into an oil pump replacement, PLEASE take Ryan's advice from his reply above...if you have to go that far into the motor, do it right and do it once! Put a new timing chain, oil pump, etc. while you are in there.
Keep in mind it may be more, which is why trouble-shooting is key. With an oil pressure problem and noises it could be the abovementioned issues or the oil pressure "bar-bell" o-ring in the back of the block to blown/worn out lifter(s), so roll yer sleeves up and get krackin'!
Sorry for the long post, I really hope it gets you in the right direction and let us know how its going!
Mike

**ls1ws6ben** · 07-07-2011, 06:00 PM

an update real fast.. bad lifter and rod knocking.. cant afford to rebuild the ls1 right now.. found a 5.3 which my boss bought for $800 and allowing me to repay him and have a mechanic to swap motors for $800.. the mechanic is going to break down my 5.7 and see if the block is still good.. if so, i will take my time and do my first LS1 rebuild.. im in no hurry and i want to research, get input and do this right.. i have a few people who have offered to help me out with this.. main thing is to make sure the block is ok.. ive seen budget builds done on spike tv, but i will name this extreme budget build.. having what main parts i can keep reworked and machined or buying bare ls6 heads and building.. have to research which is cheaper and better fit my budget.. going to be a low budget but im in no hurry..i want to do this right and see what numbers i can turn out of this thing.. mean while my car will have a smaller 5.3, but its my only car so as long as its running, i can live with that.. i do however have a friend trying to get me to put a bigger cam and springs and such to beef it up.. but i think i would rather put that into my 5.7.. assuming the block is good.. this is going to be interesting but im excited to try this

**JayTA98** · 07-08-2011, 05:05 AM

on the pressure issue i will test out by swapping the sender 1st. I had a sender that the plastic cracked halfway and it was preesing slightly against the switch creating a low pressure reading. I swap the sender witha new one and the reading was normal. You can get the sender out with a special sender socket and you can reach behind the engine. It was pain in the ass to remove the electrical plug but is easier than removing the intake.