oil light on at idle...sometimes

[alini]

On the way home from a 35 miles one way trip, the car ran great going but on the way home when I approached the first stop light of the trip (five miles in) the oil light flickered.  It jumped on then off, not glowing, solidly on and off, twice maybe three hits.  I immediately put the car in neutral and had no issue.  So we continued on.  The very next light after coming to a complete stop and a few seconds of sitting in idle the light would flicker.   As I travelled I did some testing, if I arrived at the light in neutral the light would never come on.  Only when in gear and only when at a complete stop.  It never came on, just a quick blip or two.  The car ran awesome the whole way home, no noises.  When I got home I checked oil was at the add line and clean, especially for an engine with 365 miles on it.  I topped it up and I checked my idle speed.  It was down to 450 when in gear, so I bumped it up to the book 550 and ran the car for a few moments in gear with no further issue.

This is a fresh rebuild with a new oil pump, new pressure switch.  I have cancelled attending the show that I just registered tonight for.  Due to the fact its so far from home I wanna do some local testing with it.  I need to install a gauge, just need to find the right place to put it.  Im thinking the idle speed in gear was too low and the RPM wasnt truly loaded up until I was at a complete stop.   Opinions???

 

 

UPDATE-  it was the oil filter   Since it's a fresh rebuild the filter collected the. It also break in stuff. Since I have pretty much done everything city the 350 miles at the time of the light flashing was equal to the operating time of the 500 I planned on changing the oil.  Change the filter and turn up the idle to 550 and just drive 35 miles to the show without missing a beat

 

Edited September 24, 2016 by alini
Added update for result (see edit history)

[KongaMan]

Your idiot lights are powered through the same connection as your dash lights, fuel gauge, etc.  I wouldn't bet against this being a different manifestation of the same problem.

Edited September 24, 2016 by KongaMan (see edit history)

[telriv]

Install the gauge where the oil pressure switch is located.

[rodneybeauchamp]

I chose both a gauge and a light by using a tee piece that fits the block, the standard oil pressure switch and sender for the gauge.

No brainer in my opinion. Installed a water temp gauge in at the same time, much nicer knowing what it is doing than guessing or relying on a light. 

 

Dont know why the PO put in the two push button switches below, they look something shocking, so I'm thinking a tacho might have to be installed as well. (If anyone has a good working Buick one for sale I would be interested?)

 

Hope this helps!

Rodney

[Riviera63]

Chris,

 

I had this same exact problem a couple of years ago when I was out in Colorado for the ROA Convention. We were stuck in bumper to bumper traffic around Denver. Every time we stopped the oil light came on and I had to pop it into neutral and give it a little gas and it went out. Very annoying. We got back to a friend's house where we were staying, gave it a quick tune and got the idle reset. I have not had a problem since. That was 5000 miles ago, including the 1100 miles back home from Colorado. I don't know if this is your problem but, that solved mine. 

 

Bill

[EmTee]

The symptoms definitely sound electrical, rather than mechanical.  I agree with KongaMan that this could be a different manifestation of that other pesky gremlin you're chasing.  It may also be the sending unit is right at its ON/OFF point when hot and idling in DRIVE.  If so, raising the idle slightly (as Riviera63 did), or replacing the sender may fix it.  In any case, temporarily (or permanently) installing a gauge will confirm or rule-out an engine issue.

[KongaMan]

4 hours ago, EmTee said:

The symptoms definitely sound electrical, rather than mechanical.  I agree with KongaMan that this could be a different manifestation of that other pesky gremlin you're chasing.  It may also be the sending unit is right at its ON/OFF point when hot and idling in DRIVE.  If so, raising the idle slightly (as Riviera63 did), or replacing the sender may fix it.  In any case, temporarily (or permanently) installing a gauge will confirm or rule-out an engine issue.

This is all true. 

 

It could be electrical, it could be a matter of your idle dropping below spec, or it could be a matter of a faulty sending unit.  A tach and a gauge will sort out the last two possibilities quickly enough.

[alini]

Read original post for update on condition.   Bottom line. Replaced the oil filter

[alini]

For the record I just finished a 70 miles round trip and the car ran fine.  No issues with the light.  In fact I got 11.6 mpg, so the motor is strong and it was just the filter got clogged faster than I anticipated.   I have 432 miles, next weekend I should be at 500 we will change the oil and filter again.

[telriv]

How can a new filer get clogged that fast????  I would cut open the old filter & check for any UNWANTED debris.

[alini]

The car ran 350 miles of 90% city stop and go.  Every traffic light sitting at idle for how long.  We cruised Las Vegas Blvd last Saturday in bumper to bumper traffic for about two miles.  So the engine ran for how much longer than a car on more open road in the same distance

i cut the filter open this morning when I removed it.  Nothing out of the ordinary except a lot of normal  sludge for a break in.  Just because the odometer said 350 I'm sure it's closer to 600 miles on the engine.  I'm comfortable with the fix. It ran great today

[KongaMan]

OTOH, bumping the idle might've been the fix.   450 is a little low.

[alini]

Based of the dark sludge out of the filter I'm going with that one as the prime.  Regardless it's running great right now and that's all that matters

[1965rivgs]

I`m with Tom T. on this. It would be exceptionally unusual for the filter to clog that fast. Even so, I would expect the bypass to supply enough oil to satisfy minimum pressure specs.

If you also changed the oil the fresh oil will tend to be more viscous than the used oil and raise pressure a little bit. No doubt raising the idle speed helped also.

I would install an actual pressure gauge or at least swap out the oil pressure switch for the idiot light. It`s always a good thing to be able to measure the actual oil pressure instead of guessing based on the idiot light or the calibration of the oil press switch.

  Tom Mooney

 

[lrlforfun]

OK Chris: I concur with the "put a known working  gauge on it" . The gauge won't lie. I certainly hope you won't need to take it  apart again.  Good luck, Mitch

[60FlatTop]

On a fresh rebuild or if any question arises that can be monitored with a gauge I like to watch closely, but I don't care to have the gauges hanging under the dash permanently. My '60 Electra came with a set that I watched for a while and then removed when I got to know the car.

 

 

When we did all the work on my '86 PA I put a set of gauges under the hood. I open the hood often to check things so, for me, they get checked a lot during those first few months. Once I am confident (or get around to it) they are removed.

 

Some guys on the forum thought it was pretty stupid to put them under the hood, but it works fine for me. I'm looking for more of a trend rather than an immediate failure.

 

About 10 years ago the HOT light on my Riviera started coming on, even when I knew it was cold. I put a temporary gauge in the sensor well and tie wrapped it to the AC liquid line on the inner fender. Everything was fine. I open the hood on that often, as well. Maybe I'll get the new sensor this year.

Bernie

 

 

15 PIS difference between the Mac and the Sunpro, just a gauge.

Edited September 27, 2016 by 60FlatTop (see edit history)

[RIVNIK]

I consider an oil pressure gauge to be one of the most important features on an old car, even one with a newly rebuilt engine. Way more important than a clock, especially for me ( I always have a wristwatch on, and I have a quick-disconnect on my battery for when I'm not driving, so my clock was only right twice a day anyway.) I removed the clock and found an oil pressure gauge which matches the appearance of the other instruments. it's a perfect fit and also in the perfect location, front and center. Nothing has given me more peace of mind. The clock is in storage.

[Guest dwhiteside64]

I wing it the old school way and go by the sound of the engine....  

[60FlatTop]

Any of the basic systems, lubrication, cooling, charging, and the like, if inspected and maintained on a regular basis are more reliable than the gauge you might find to monitor them with.

 

My first experience in this concept happened about 25 years ago. Liebert builds the best quality and most reliable computer room and IT air conditioning units available. So I'm checking one over and find no oil pressure cut out switch for the refrigeration compressor. I found out that down time had been caused by failed pressure switches and the lubrication pump rarely, if ever, failed. The safety switch was deleted to improve reliability.

 

Got to a parts supplier and ask for a gauge. The guy slaps one on the counter in seconds. "We sell those all the time." Ask for an oil pump. "Oh, that's not a stock item. I can have one in two days."

 

Cars are the same. My gauges are installed right after the fingers have been in there monkeying around. I trust the system. I don't trust the mechanic. Once I know the system is functioning I maintain it and really don't pay attention to the gauges, and like my '60 Electra, I remove them.

 

My Chevy has an engine oil cooler. That line could rust through and pump all the oil out while driving. I'm not worried. It is something I check.

Bernie

[DiskHarv]

On ‎9‎/‎27‎/‎2016 at 10:50 PM, RIVNIK said:

I consider an oil pressure gauge to be one of the most important features on an old car, even one with a newly rebuilt engine. Way more important than a clock, especially for me ( I always have a wristwatch on, and I have a quick-disconnect on my battery for when I'm not driving, so my clock was only right twice a day anyway.) I removed the clock and found an oil pressure gauge which matches the appearance of the other instruments. it's a perfect fit and also in the perfect location, front and center. Nothing has given me more peace of mind. The clock is in storage.

 

[DiskHarv]

I'm having my 425 nailhead rebuilt and I want to follow your lead replacing my clock with an oil pressure gauge  It would be a great help if you could tell me what gauge you used and where I can order it along with any other pointers in putting in.  Thanks again for your help !