Thanks for your prior compliments btw, but just a reminder, I’m a driveway diy’er and no experience w/that particular vehicle. If I had that problem and noticed nothing obviously wrong during a visual inspection, I’d start w/using a scan tool to check the fuel trims. That will give you needed data to base a next step on. Suggest you have a shop do this for you, if you can’t do it yourself. They may figure out what’s wrong just by doing that, then if you want you can fix it yourself. I’d probably also use the scan tool to check the O2 sensors basic operation, and possibly do a fuel-rail pressure test.
I expect however that you’ve got a vacuum leak of some kind, given the lean code and the higher than normal idle rpm. I’d start w/the starter spray (or propane) test for that. If the pcv valve is simple to replace and the part inexpensive, you might just swap it out w/a new one on a flier.
You may be a shadetree mechanic by definition, but you don’t need to get a paycheck from GM to make you an expert, which you clearly are. Where is a good place to get the scans you mentioned? My mechanics have a high end scanner, but it’s a handheld and I don’t think it can isolate components in the way you detailed. Thanks GSJ
A couple of questions if I may, I’m topping off my coolant every 3-4 days and the place I park has fresh wet fluid on the street every day, what can one expect to pay for the labor on a water pump? Why do I have a “low coolant” error on my driver info console even now when I’ve topped it off? I’ve been topping this off for a year and the message has always gone away once I did? I had the hoses replaced this summer if that matters.
Tommy
BTW When I saw my undercarriage when my friends at the shop were replacing the serpentine belt last week, it looks like someone took a lube gun and shot the front half of my car. One said the valve cover gaskets were leaking, but it looks much more like the oil pan gasket given the location of the wetnesss (the oil pan is saturated). Would you go after the valve cover gaskets or the oil pan gaskets first? (and how could he even tell if the valve cover gaskets were shot from under the car, when it’s clearly soaked the oil pan itself. It may as well have a sign that says “your oil pan gasket is leaking”. Of course I realize this is also probably the coolant leaking from the water pump housing and spraying the underside of my car. I’m adding about half a quart of 10-30 every 2 weeks
I think the water pump cost me about $100-150 plus the pump after I spent all day trying to get it out with the special tool needed and had to take it to the dealer. The dealer has the $20,000 equipment plus people trained-although they are disappearing fast that know anything about that car. What can I say? You’ve got an oil leak, coolant leak, some electrical issues developing, etc? The engine breaks in half so you don’t just replace a pan gasket like regular cars. Please consider again whether it is time to end the misery. They were great cars when new but should be disposed of before the 100K mark.
It may take a few miles of driving to clear that warning light. Or the place you are topping off the coolant isn’t where it is measured low. From what I can tell the coolant level is measured in the radiator, and you are probably topping off the overflow bottle. With a coolant leak in progress the radiator and overflow bottle levels usually don’t track well.
If your 96 Olds is OBD II compliant (most 96 models are) then most any pro shop that works on GM cars should be able to do that for you. A GM dealership is the backup. They’d have the GM scan tool. If it is OBD I, you’ll have to find a shop that has a digital lab o’scope and knows how to use it. I don’t believe fuel trims are possible to measure on OBD I cars. But checking the O2 sensor signal should be.
Just a guess , but I’d budget for about 2 hours labor & $50 - $100 for the replacement pump. Note that small coolant leaks can occur in places other than the pump. I wouldn’t assume it is the pump that’s leaking myself, unless I actually saw a leak occurring there. There’s usually a small hole on the body of the pump, but near the pump’s pulley. On the top or bottom or both. If the dynamic pump seal is leaking slightly the coolant will usually drip out of that hole. It you only see a little dampness in that hole, but no coolant dripping out, that’s probably not a sign of a bad pump.
In my experience valve cover gasket leaks are much more common than oil pan leaks. Unless you have a reason to think there’s an oil pan leak (like you banged the oil pan against a big rock or curb one time), I’d bet on the valve cover being the oil-leak source. I’ve had several valve cover gasket leaks on my Corolla, but never an oil pan leak. There’s so much wind in that area as you drive down the freeway that where the oil is now usually is unrelated to were the leak is. A shop could figure out the source of the coolant leak and oil leak at the same time. That’s probably the way to go. This is something shops do all the time, so they know what to look for. If all else failed they could clean the engine as much as practical then use a dye/black light tool to find where the leaks are occurring.
Hey Bing,
I hear you about the headaches, but unfortunately my wife just had major surgery, insured but 20% of $50K is still a big #, plus her tranny gave out last month at just 70K (GMC Terrain), add my car and we coughed up well over 5 figures in a month. Anyway, we believe in cash and carry so no credit cards and we are about to pay off her “new” SUV after 6 years…we won’t lock ourselves into another loan anytime soon…so the Aurora has to stay.
Today the passenger seat died, I’m on board with your diagnosis, just far too many components are failing for it to be the units themselves, there’s a ground issue or damage at a wire bundle, I’ll start looking asap. Thanks so much for your time and research!
I have a question you may be able to view. i know of a broken ground wire, if you are in front of the car, hood open it is on the left side. it begins from the top left corner of the pretty intake manifold cover (underneath it) and it was mounted to a bolt just outside that location on the block. The clip is still bolted to the block but the broken wire is now missing (perhaps my mechanic tucked it back underneath the manifold cover. i would guess it to be about a 16 gauge, just a bit thicker than the typical wires used in 90% of most electrical stuff which is 18 gauge.
Can you see a single wire that begins under the back left corner of the manifold and ends just outside it on a fat bolt on the block? No other wires would be anywhere near it on the block, I havent pulled the cover off to see where it begins. Thank you
George, my mechanic put it on the rack and showed me a slow drip coming from the very end, just as you described…no reason to think the water pump is ready to quit, and you’re right, the oil is clearly from the spray, not the oil pan gasket. I think we must next deal with the car running too lean. It’s idling a bit too high, and just feels like it’s rough also. I guess I’ll let my mechanic try to scan it, but if his scanner is inadequate I’ll have to pay for a real scan.
Low oil pressure at idle only, will most often mean that the engine is low on oil . As more power is applied to the engine via acceleration, the pressure builds up inside the engine. … High oil temperature can cause low oil pressure . A defective oil pump can also lead to low oil pressure at idle .
Probably the high temperature is causing the the oil pressure to fall at idle.
Need your advice, so my ,96 Olds Aurora (big V8 Northstar Motor from Cadillac) is making a quiet grinding noise at the motor where the pulley belt attaches, so my water pump is going out soon. My mechanic is also a friend, says it needs a special tool to pull it, and will charge me $250. While I have this off, anything else I can repair to save labor next time? I can tell you my coolant was almost pouring to the ground and I had to add a half gallon of it daily until I used stopleak, it worked for a month and the leak returned, same time as the bearings in the pump began making noise…Fair price? What else can I address with the H2O pump pulled? I know I have a valve cover gasket leak (1/2 quart of oil every week or so) Thanks