85 losing oil pressure at idle
 

Well guys this might be the end of my rx7.

Over the weekend I drove it home to show it to some friends and family. Home is about 100 miles down the road. Well on the way home I noticed that the oil gauge would fall to zero sitting at idle but cruising down the road it would hold a steady 60. I know the gauge accuracy is garbage at best but its a good reference. When I had the rear end leak fixed I went ahead and had them change the oil in the car for me since I can't do it myself because I live in an apartment complex. Ever since then the car has done the idle oil psi drop. I'm afraid that the engine might be on its way out and I don't have any money to keep throwing at the thing.

So I know the problem could be one of these:
1. the oil pressure sensor is going out (doubt it but that is what I am hoping for)
2. the oil is thinner than what was it is and its losing pressure that way.
3. the oil pick up tube could be clogged
4. the stupid o ring on the front cover is bad and shrunk since the previous owner put synthetic oil in the car
5. the engine could be about to die

If the engine is dead idk what I will do. I have to much money to sell the car with a bad engine and not get any money back. Any ideas would be great help.

If all else fails I will just keep on driving it and hope for the best since I have read people have done that and not had a problem out of there cars.

Thanks Josh

Check your oil level. Remember that our cars inject oil with the fuel to lubricate the apex seals, so you can expect to go through it when driving and need to replace it in the oil pan. Also, if the oil change place shorted the new oil, or didn't account for a new filter being installed, the low oil level could lead to a drop in idle pressure.

This is why I don't trust oil changes to anyone but me.

Check the simple things, and you need to learn to work on your own car if you intend to keep it. Routine maintenance should be in your inventory of skills no matter what car you're driving.

My fb does the same thing, but runs fine. Should I be worried about it? It's oil level is fine and I don't notice any leaks.

I have already done all of that. I would change the oil myself but since I live in an apartment complex I can't. I drove the car 500 miles since the change and the oil has come down a bit but not enough for me to add any to it.

I do my own mainteance when I can like I replaced the radiator and hoses this past weekend.

85 losing oil pressure at idle
 

Call and ask what weight oil they put in it, should be in their records, if its not the recommended, it can lose oil pressure

Another question is what oil filter did they put on? If you didn't have this this problem before the oil change, than its something they did or didn't do

10w40 is what they used and some normal brand oil filter. Though it does seems smaller than the one that was on it before. But the guy that did it before didn't know what he was doing because he used synthetic oil instead of dino oil...

Synthetic oil won't hurt it - it just won't burn very cleanly when it's injected and that's why we all tend to stay away from it, apart from the price. With how often we need to change the oil on our cars (because of OMP injection), it doesn't make good $$$ sense to spend that much on oil.

If the oil pressure is good at RPM, is at or above the 'Fill' line on the dipstick and you don't have any obvious leaks - I'd just drive it. Could be a bad gauge and these are not known for being all that accurate in the first place. As long as you're getting good oil circulation and it's clean oil, you should be fine.

I wouldn't worry about it too much, but watch engine temperature to be sure it doesn't spike. If it does, shut it off and let it cool down. HIGH temperature would be anything more than 1/2-3/4 on the coolant temperature gauge and at that point you're well over normal and need to shut it down. HTH,

I'm trying not to worry about it but sitting idle for awhile and then driving it sometimes takes the pressure quite a few seconds to come back up to pressure. But it overheating is not going to be an issue at all since I put the mazdatrix radiator in it. It barely gets over the first line on the gauge after the cold line. I'm thinking about picking up the harbor freight oil pressure tester kit and just checking to ease my mind on everything.

you should do that, its really rare for these engines to actually have oil pressure problems. usually the pressure falling at idle is the sender

...and sender units are cheap.

Subbing. Same problem in my gsl-se. Started suddenly s few months ago. Good pressure until I sit at idle.

My car does not burn any oil though, I think the omp is broken. I don't know if that could have anything to do with it. In just run premix for now since its running fine otherwise.

So I messed with the wire on the sending unit last night and the signal seems better but still drops at idle. I also bought the oil pressure check kit from harbor freight and I'm going to actually check the oil pressure. If it's good I'm going to buy a auto meter three in one setup with water temp oil pressure and volts since my voltage meter works when it wants to.

I had some slight corrosion on the wire terminal/clip for the oil pressure sending unit last summer. I was getting some really funky readings.....cleaned up the terminal, clipped the wire back on, no more problems.

Well i did the pressure test like 15 minutes ago. I'm afraid I didn't let the car warm up enough but it was above the second line on the water temp when I finally had to shut it down. It was leaking oil while it was sitting there from one of the fittings for the tester so I didn't want to leave it running for to long but at idle it was at 30 psi and it would dip down to like 27 then pop back up.

I also am almost positive that it is the sending unit now because right after I started it up the gauge went to high pressure and then fell back down slowly to zero then came back up to the 30 line all while it was still warming up.

Thanks guys for the help. Anyone know where I can get a new sending unit for it without having to go to oreillys for the 50 dollar one??

Thanks Josh

step 1, never go to oreillys for anything more than fluids/batteries/light bulbs... i've fixed many many Rx7's by just replacing everything that said "made in usa" on it, with real OEM parts

for the sender i believe rock auto actually has an oem one for like $20...

Alright I'll look it up and buy it tonight

Thanks fellas