97 T&C 225000 low oil pressure at stop signs.

First clean the pressure sensor plug with contact cleaner. Was the pump actually replaced or just the bent pick-up tube? Did you actually request to see the parts?

Take out the oil pressure sending unit, replace it with a T-fitting reinstall sending unit hook up mechanical gauge it is simple.

BIG BIG MISTAKE!!! on 20w50, use the correct vescosity in your ownres manual. A heavier weight oil WILL cause premature oil pump failure, along with bearing and ring failure your engine was not designed to run on that viscosity.

Coasty

Sure, get a mechanical oil pressure gauge from your FLAPS and use a tee-fitting wherever the sender screws in (probably on the head somewhere, but may be on the oil filter mount.) you'll need to find a hole in the firewall through which to pass a tiny nylon piece of tube, but that's it. also will need to find the dash lights circuit if you want to read the gauge at night.

You should read *some* pressure at idle, at least 7-8 PSI, and at least

10 PSI/1000 RPM when driving. (NB: these are generic recommendations. The actual repair manual for your vehicle may have slightly different specs) If you lose pressure by more than a couple PSI when you stand on the gas, but it immediately comes back when you lift off, that's a sign of excessive rod and main bearing clearances and your next step should be to drop the pan again and roll some new shells in there. If nothing else loose rod bearings can confuse your knock sensor and cause driveability problems.

Thicker oil will definitely "help" if the only problem you have is low oil pressure (i.e. there's no rattling or knocking.) I know my Porsche looks like the bearings are about shot by the gauge when running Mobil 1

0W40 but after switching to Rotella T 5W40 - which isn't even a different grade, just towards the heavier end of the 40 weight spec than the Mobil - it looks a lot better.

Is it possible that you have a bad oil pressure sender? IME when they've failed, they tend to fail by not driving the light (won't light up with key on/engine off) but I have heard tell of them failing the other way. The only way you will know is to hook up a gauge and see what it says.

good luck

nate

(doesn't drive cars without oil pressure gauges, except for the company heaver.)

I would suspect the sensor. Why did you switch from Mobil 1 to Quaker State? Not a good move.

Matt

At 220+K miles, I'd suspect the oil pressure sender switch may be worn out. It is fairly inexpensive and easy to replace, so I'd try that first. While you have the sender out, you can hook up a regular mechanical oil pressure diagnostic gauge and measure the actual oil pressure under idle conditions and watch it as the engine warms up and the oil thins out.

If the new sender doesn't eliminate the flickering, then I'd suspect the oil pump or possibly a clogged pickup, although the mechanic that removed the pan and installed a new one should have made sure it was in good shape before reassembling. This is why I'd suspect the sender first.

On the heavier oil, I'd personally not use the 20W-50. I'd go no higher than 10W-30 and in winter if you are in a colder climate, I'd keep to the recommended 5W-30.

Bob

Let me be the third vote for a bad pressure switch. Replace it and your problem will go away. It would be a good idea, as others have suggested, to actually measure the pressure for peace of mind.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

A bad connection is not his problem. If it were, the light would not come on regardless of the oil pressure.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Thanks for the insight, everybody.

The pump and pan were replaced. As to old parts, no I didn't see them. But, I'm pretty sure they put in a new one (I was doing some computer work for the dealer, they offered discount on labor to 'employees', and they were doing me right). The actual mechanic, on the other hand, was too busy to move to the next task to discuss much. The service manager said hey, he's good, he's fast, and he's not real talkative.

They didn't remember my comment on Mobil 1, and didn't recognize what the case of it was doing on the floorboard of the passenger side. Oh, well. So that's why the Quaker State.

I'm not real mechanical anymore since losing the use of one arm in a little motorcycle adventure. But I'm going to have to get someone to help me with a guage. As someone said earlier in the thread, all of his vehicles have guages.

I must say, I've already done an oil change with some mineral based

20W-50. Perhaps the reason I've gottten so many trouble free miles is the Mobil 1, but I've had more than a few gearheads tell me that at 5k changes I'm just spending extra bucks. At a quarter of a million miles, I've sort of gotten my use out of the thing, and I shan't expect another quarter even if I use synthetic.

As to dropping the pan and rolling some new shells in - yikes! I haven't seen the crankshaft of anything except my model airplane engines in years. I just can't get that deep into things anymore. I've been 12 years with one arm dangling, and most folks are surprised I even change my own oil still. With the quality of service this T&C has given me, I'll buy another when the day comes. What a bullet proof vehicle. 160k on the 1st transmission, one replaced alternator, replaced brake disks once, and some a/c work (new evaporator/condenser or whatever it is that looks like a radiator under the dash), I simply can't complain. Even the driveshaft to the AWD is original, though the boot has been torn for a few years. Original shocks/struts even (wheels still don't hit the fenders). I live on a dirt road and it ain't like it'll ever drive like a new vehicle again. Alas, it has a nice stereo.

Anyhow, you folks have confirmed that it should be easy enough to install a gauge. And that a dirty or faulty sender could be replaced at the same time. As to replacing the oil with 20W-50 and it not being recommended, I'll hope I haven't signed my death wish. We'll know if I throw a rod on my little trip. I'm under the gun, and had already made an executive decision prior to getting back to my computer. I'll report back in after I go hopping across the country to visit my crazy brother.

Again, thanks everybody for the insight.

Clayton

You may well be spending extra bucks, I won't argue that, but I live in a cold climate and the much better cold temperature cranking makes the Mobil 1 worth it for me even with 5K changes. My 96 GV has 178,000 miles on it now so I just lenthened my change intervals to 10,000 miles rather than switching to dino oil. I cut my costs in half that way and since I no longer care if this van lasts much longer, I see nothing too lose. However, I've been using the 10,000 mile intervals since 150K and so far, I can't tell any difference! The oil is a little blacker at 10K than 5K, but barely enough to tell the difference. The old 3.3 uses about a quart every 1500 miles, so it gets 6 or so fresh quarts between every change anyway. It has used this much oil since I bought it with

33K on it, so nothing has degraded oil consumption-wise in nearly 150K miles. And the engine is as quiet at idle or WOT as it has ever been.

Yes, installing a gauge is the best way to confirm your problem. I'm still betting on a bad pressure sensor, but it could be something more serious. The gauge will help you know.

Matt

I started using Mobil 1 back in the days of my Moto Guzzi 650. The racing guys at Daytona swore it was worth another 5 mph or half a second or whatever. And my 93 Dakota did 175k with no trouble (guy I sold it to for 3/4 of what I paid for it said it was the nicest vehicle he'd ever owned). It never used oil, and the T&C still doesn't. I like the stuff.

That said, the spousal unit's 2001 PT Cruiser has used a little since day one. 75k, and no worse than at the beginning, but I add 1/2 qt every 1500 miles or so. Probably twice between changes (5k) anyhow.

A gauge. And a sending unit. I'll hope one of my motorhead friends can help me out.