Need help with oil light coming on in AE95/4AGE setup - Toyota Nation Forum : Toyota Car and Truck Forums

Fastphil · 12-31-2008, 03:26 PM

I'm new to Toyotas, and I have an issue that has cropped up on my car in the last week or so. It is a 1989 AWD Corolla with a 4AGE 16 valve engine in it. I suspect the previous owner didn't divulge much information about the car when I bought it a month ago, but I don't blame him. I didn't ask enough questions when I was looking at it. Anyways, here I am asking for help.

The car was built for rallying in 2001, and it has a rollcage. THe engine swap was done at this time as well. The engine runs fine, pulls to 8000 RPM, idles fine and starts almost instantly in any temperature.

Lately, the oil light (good ol' dummy light on the dash) has been coming on at idle after the engine has warmed up and been driven for 15-20 minutes. The longer I drive it, the more the light comes on. I've seen the light on up to 4000 RPM recently. If I was really having a problem with oil pressure, the engine would have seized a while ago with the way I drive it. I don't care much about this car, but I don't want to fry the engine either.

So, what with the engine swap and all the other things done to the car, I'm thinking there may just be a loose wire somewhere that is causing the light to come on. Is this possible? What information would a bad sender give? Light or no light?

I'd be interested to see what the oil pressure is, but I don't want to go through the trouble or cost of installing an oil pressure gauge. Is there some way I can tap in with a temporary gauge to check the pressure in a shop?

From what I've read/seen about the 4AGE, the sender is right there on the front of the engine with a single wire coming out of it, so checking that should be simple, but what am I looking for?

Oil level isn't extremely low, about halfway on the hashmarks on the dipstick. I will add more oil, but I suspect this is not the root of the problem. What kind of oil does the 4AGE like?

Any help would be appreciated. I can get pics if necessary, and if you need any more info, just ask. I'm mechanically inclined!

Thanks,

Phil

***toyomoho*** · 12-31-2008, 06:58 PM

The current oil pressure sensor can be removed and a gauge temporarily installed to check pressure.

Fastphil · 01-11-2009, 05:50 PM

I topped off the oil, and seems to have helped a bit, but I'm still getting the oil light at idle and low RPMs. Anybody else have any more input on this?

Fastphil · 02-21-2009, 05:09 PM

Here's an update for anyone enlse who might be having this problem. I took the car to my friend's garage that specializes in Toyotas (CP Performance in St-Jean-sur-Richelieu, Quebec). Actually the car was there because of another problem, but I had him check out this one at the same time. Turns out the oil pressure sensor switch is broken. He said it's easier and cheaper to just install an oil pressure gauge than to replace the switch. After all, knowing what your actual oil pressure is is better than knowing if it's either zero or something, as the stock dash light serves.

He also mentioned that the 4AG can apparently run for a pretty long time without any oil or oil pressure in it before it will self-destruct. :O

***new echo owner*** · 02-23-2009, 01:07 AM

Having an oil pressure gauge install on the vehicle is a good idea. The oil pressure switch usually turns off the light a a fairly low oil pressure, less than 10 psi.

Any engine can run without oil for a short period of time; however, unless there is no choice I would rather leave that as an un-test theory, and make sure there is enough oil and good oil pressure running through my engine.

N.E.O.

Fastphil · 02-27-2009, 08:05 AM

Well I picked up a cheapo mechanical oil pressure gauge and had my friend install it. Oil pressure is fine, showing 25psi at idle when warm, and over 60 psi at highway speeds.