I'm at wit's end with my car right now. I recently installed a TR227/224 cam with 918's valve springs and LS6 intake. After I fired it up, it was on the low side of the oil pressure gauge. I thought maybe the pump was getting crappy (since its a 98), so I splurged and bought the ARE ported unit. I put it and installed a new pick-up tube o-ring aslo. When I fired it up the second time, it read ZERO oil pressure. So, I poked around and found out that I broke the oil pressure sender, so I replaced it. Now on my third start up, it fires up and is holding 60psi (cold idle), as it warms up it falls down to 40psi, then 20, then 0. Now I dont know what to do anymore. I've checked multiple times and I have plenty of oil and there are no leaks. I'm wondering if it is possible to trap a pocket of air at the end of the pressure sender to throw of its readings?

Anybody have a clue on what could be wrong or what to check??
Thanks, for any info or tips.

<small>[ February 18, 2003, 06:25 PM: Message edited by: felton316 ]</small>

 

Does it knock when it goes to zero??? It should if it actually is. I would say hook up a manual pressure gauge, but it is such an odd thread (16 mm 1.5 thread pitch) it will be hard to hook up. Auto barn sells an adapter to get it to a usable thread but that would take a few days to get. As far as air by the sender... That would not be it. It would still be able to read the air pressure which will be the same as the oil.I hate to suggest to start thowing parts at it, but is it possible the new sender is bad???

 

Yeah, I'm gonna try another sender tomorrow. It doesn't knock when it hits zero. I removed the oil filter and put in another dry filter (totally empty of any oil), then ran the motor for about 15 seconds, then removed the filter. It was full of oil and more came pouring out behind it, so I know oil is moving through everything. Hopefully I will get better results from tomorrow's sender. If that doesn't work, I'm not sure what I'm going to do..... Anybody have an extra stick of dynamite?

 

Well I installed another new sender and this one is showing ZERO oil pressure. Anybody have any suggestions?? Can the wiring harness be checked for continuity or a specific voltage? Or do I need to pull the whole front of the motor off for a third time?

 

Any one know of a port I could use to install a mechanical oil pressure gauge?
TTT

 

Do you have driveability problems? Idle OK, but runs poorly? Your cats could be clogged. This causes excess back pressure forcing the oil back down into the crankcase below the oil sender. The sender misreads the problem as low oil pressure which you really don't have. Gut your cats.

 

If you really had zero oil pressure, your engine would be really loud after your lifters stopped pumping up. Ask me how I know.

I would get a mechanical gauge and test it, it's probably the sender or some wiring. Problem is I never did find a gauge that would fit there, but I'm sure a shop or the dealer would have one.

 

I would take off the oil filler cap when the engine is on and there is zero pressure showing on the guage.


On a normal engine with oil pressure, you can see the rockers and springs moving around and being well lubricated by the oil pump.

Do this or suffer the consequences of a dead engine. I doubt it is a bad pump becasue you would here some nasty sounds but it never hurts to be safe.

 

Well, its not a clogged cat problem, cause I dont have cats. It seems to idle alright, I haven't driven it anywhere, afraid of the damage I might cause. I fabbed a 16mmX1.5 to 1/8" NPT fitting today at work, so when I get home I'm going to try a mechanical gauge and see what it reads. I've been through 2 new senders and only one worked for about 2 minutes.

 

One weird thing is that if I check the oil with the engine running and showing 0psi, the dipstick is totally dry, like if there was no oil. But, when I turn the motor off, the dipstick shows full. Its got about 6qts of oil in it right now.

 

Sounds like something might be blocking your oil return passages in the upper intake valley. I know this is dumb, but you did take the valley cover "Rag" out before you put your intake on? Wrong intake gasket? The heads were NOT pulled... Correct?

No insult intended, but many of us have done .......well stupid things!

 

...i agree with HD. If you dont have oil showing on your dip stick when the motor is on, there is no (little) oil in the pan...that would explain the low/no oil pressure gauge reading. WOW!!!

...check the valves/rockers for oiling when the motor is on. Do this with the oil filler cap off!

Do not run the enging without proper oiling for a long time!!!

 

your main bearing are probely gone. if there is to much clearnce that will cause this. just happened to my freinds z28.

 

I'm going to check this weekend for any rags, that may have been left behind, but I doubt it. I haven't ran the motor long since this has happened. There is no intake gaskets involved (all o-ringed).

 

I don't believe you would have taken the valley cover off to install a cam or intake. True on a typical SBC but not an ls1. So that would not be it. But one usually does stuff one in the front of the pan to keep the bolt for the pickup from falling in. That rag could have been left in there and blocking the pick up. Or possibly forgot the put the bolt in the pickup tube. Like mentioned above. Don't feel bad if you did we have all done stuff like this at one time or another. <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />

 

Well, I'm gonna check everything for rags this weekend. I'm getting pretty good at removing the front end of an LS1, so it shouldn't take too long anymore. I did do the LS6 valley conversion while I was installing the cam, so I will check there too(at least it can't hurt). I know for sure that the pick up tube bolt is, because it has been the hardest thing I have ever done ever!! But, the rag behind it could still be there, so I will check for it too. I might even sneak one of the bore-o-scopes home from work and look around in all the little tiny places, just for fun.... I mean its not like I'm going anywhere this weekend. The best part is that my other car (5.0 mustang), just fried the electric fan. Two cars and none are working.... What next snow in Texas?

Thanks for all the help so far.....

 

any new news yet??

 

....so what do you find when you tore down the motor again???????

 

Any news?!?! You got everybody wondering!

Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />