oil light under idle bad?

[38SHO]

so my car idles at about 900 rpm or so, just under the 1k mark... sometimes it dips below the idle mark comming up to a light when I hit the clutch and the oil light will come on for a second

so is this bad?

normal cause I'm below idle so I'm not pushing as much oil PSI as the computer wants to see?

oil pump wearing out?

rod bearings messed up?

never does it at idle or regular driving......... only at rpm's below idle

10w-30 oil in south florida, fresh oil, full to the mark on the dipstick.......

 

[hawkeye18]

Seeing the oil light come on at idle is somewhat akin to seeing a man clutching at his chest, saying his left arm is numb, and falling to the ground. Seeing the connection here?

You need to a) immediately stop driving the vehicle, b) change the rod bearings RIGHT THE **** NOW.

If you ignore my advice, you may go for another 300-1000 miles before you spin a rod, but every mile you drive on the failing bearing is only making the damage worse. Changing the rod bearings costs about $70 in parts, and maybe $200 in labor at a shop. Less if you can find a SHO savvy guy. This might seem like a lot, but try pricing a new engine, or a new car...

 

[Storm-Chaser]

The [ OIL ] idiot light comes on when pressure at the switch drops to 6-7 PSI if I remember correctly.

That's pretty low . . . .


Another way to look at it,

- yellow = caution

- red = danger


I had this happen the first time I ran 10W-30 during the summer, and only if the rpm dropped to ~500rpm. I immediately drove back on base and changed to 10W-40 - and I haven't seen the light yet. Try 10W-40 as an interim until you can get some rod bearings in, realizing that if the light was fickering on-and-off you were operating at 6-7 PSI. If it is/was a steady red, you have no idea how low the pressure dropped and/or what damaged may have occurred.

 

[38SHO]

it doesn't come on at idle though, just below idle speed

hmm I guess rod bearings it is

 

[38SHO]

its got 150k on the clock too so its about time from most people's experiences to change em out

 

[38SHO]

also one more thing... whats with the low oil pressure? I never understood how a bad rod bearing takes out oil pressure... can someone explain please?

should I try to find another oil pump to put in there when i do the job?

 

[SHO92]

The oil light at below idle (~500rpm as was mentioned) is perfectly normal. The engine isn't turning fast enough to keep the oil pump spinning fast enough to generate the ~8-10 psi at idle.

I'd change the bearings for good measure, but I don't think the engine definitely has a problem.

 

[itwonder]

It sounds like you need to do the idle reset procedure. That may be all you need. Be sure to have A/C and headlights on when you do the reset. A forum search will find the procedure.

 

[38SHO]

kk I'll check into these few things

so its prolly ok to drive my car to work etc.. maybe I'll change them this weekend

 

[hawkeye18]

the rod bearings are the first place the oil goes after being pumped out of the pump. Normally, the bearings are clearanced at, what, 2-4 thousandths of an inch? This creates a lot of pressure in the oil, and this pressure keeps a film of oil on the bearings, keeping them nice n happy. When those bearings wear down, the clearance increases, and I'm sure you know fluid dynamics well enough to know what happens next.

The resultant loss in pressure causes that film of oil to break down, and allows the rod bearings to rub on the crank. That wears them down even more, and by the time the red light of death comes on, the bearings are dangerously worn, and at risk of locking up.

But hey, it's a free country lol. Yes, there is a chance that it's just a false alert... after all, it might just be chest pains.

 

[38SHO]

im on it, if anything I got a spare engine I can get

 

[0V3RC10CK3D]

I wouldn't drive it at all, not worth it. You'll thank yourself if you can find a ride til you get the bearings changed, swapping the engine would be a pain in comparison to just putting in some new rod bearings.

 

[SuperHO]

His bearings ain't bad. His car just drops below idle from time to time. Mine did this less than 5k after doing rod bearings when I had an IAC crap out on me. Don't get him scared for no reason.

Now, if his oil light came on and stayed on at idle, that'd be a different story.

No worries, mate. Fix your idle, beat your IAC a couple of times and you should be fine. If you wanna do em, feel free, but at this point, it's not life threatening.

 

[0V3RC10CK3D]

It depends on how far it dips, if it dips under 4-500 then you're right, he's fine, I'm assuming he meant a slight dip though like 800 or so

 

[Howdy_Doody]

I'd change the oil light sensor, they can deteriorate with age. My light would come on occasionally at idle at 95K. I put in a new sensor, and drove it for another 35K before changing the rod bearings. The bearings were probably good for another 50K.

 

[SuperchargedSHOguy]

im on it, if anything I got a spare engine I can get

+40's 3.2?!?

 

[Mr95Gl]

Sounds like its an oil pressure sender/switch issue. $5 at AZ, and 10 mins (if that) of your time. I'd do the rod bearings for good measure though.

 

[Eric VerValin]

Ok... well we are all agreeing that the oil pressure is getting .. "too low". Buy the $5 sender, reset your idle.. then change your rod bearings.

150 is plenty, I wouldn't really push it if I were you. Yea you have a spare engine, but do you really wanna swap that thing out? Mine was running fine when my bearing spun. I mistook the slight ticking as something to do with my TOB, or a chain tensioner.. I knew the rod bearings were something that was on the list to do, but was looking at everything else when it spun.

Good luck. hope you figure it out the cheapest way possible.

 

[38SHO]

yuz Chris i need those plus 40's...... I might take kelvin's spare 3.2 here in a month or two.... I want a Yamaha paperweight... plus how cool is a 3.2 as a room decoration

 

[SHO_DOODmorrris]

yuz Chris i need those plus 40's...... I might take kelvin's spare 3.2 here in a month or two.... I want a Yamaha paperweight... plus how cool is a 3.2 as a room decoration

lolz.
As for the IAC better replace that 2 it sucks when it goes... i was sitting with a 3000 rpm idle at a red light so either you get stuck with it at like 500 rpm or way high lol.
As for the rod bearings you might as well change them, im going to right away here and i guess it couldent hurt doing a pump/sender replacment while your in there. good luck

-Mitch