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Hello I have a 1986 buick regal with a 307 olds engine in it im getting a oil choke light after driving for awhile it only comes on at stops I have put a edelbrock intake and carb on it not sure if the car was doing this before hand I put these parts on directly after buying it listening to my cuzzin who is a mechanic the intake has no egr and I caped a few vacuums on the intake as well.
Suspect the oil sensor sending unit needs replacement. The oil sensor (I believe) should have one wire if I'm not mistaken. With the IGN in the ON position, ground the wire to the oil sensor sending unit - if the dash lamp illuminates the sending unit is bad.
I see another very dangerous situation there. It appears in your first pic, you have a rubber gas line from the fuel pump to the carb. I have seen many special cars lost due to that same thing. Get rid of it and put in a steel line. If you have to use rubber at each end, make it as short as possible.
I see another very dangerous situation there. It appears in your first pic, you have a rubber gas line from the fuel pump to the carb. I have seen many special cars lost due to that same thing. Get rid of it and put in a steel line. If you have to use rubber at each end, make it as short as possible.
And make sure the fuel line is rated for current gas/ethanol blends because ethanol will eat regular gasoline line
Oil/choke warning can be several things. Actual low oil pressure, faulty sending unit, or the electric choke heater coil which is wired into the oil pressure switch circuit.
Not sure if 86 307 QuadraJet in G-body was using an electric choke. Joe P will know and offer advice if he sees this thread.
I see another very dangerous situation there. It appears in your first pic, you have a rubber gas line from the fuel pump to the carb. I have seen many special cars lost due to that same thing. Get rid of it and put in a steel line. If you have to use rubber at each end, make it as short as possible.
interesting will look into that I recently put a spacer on cause i though I was having a vapor lock but that maybe the other issue I'm dealing with thanks
The OEM carburetor had an electric choke that was wired up to work with the oil pressure switch. The carburetor that was installed has a manual choke. After the installation the electric choke wire was left disconnected. That is why the Oil/Choke light is on. You may have to change the oil pressure sending unit and modify the vehicles wiring to get the oil pressure light to function properly with out an electric choke.
To help you further please tell me if your car has a gauge cluster or indicator lights, how many terminals your pressure sending unit has, and a clear picture of the wiring to the current sending unit.
I included the OP/Choke diagram so I can early refer back to it.
Maybe Joe Padavano can help out here and let us know if there are OP sending units that are normally open and normally closed.
Last edited by Dynoking; August 2nd, 2022 at 05:01 AM.
Was this car originally a V6? The 307 cars used a hot air choke, not an electric one, and did not have the same OIL/CHOKE functions as the V6 cars. Also, the gold engine paint suggests that this is not an original 307 (which would have been black). Post a photo of the block casting number above the water pump.
The bigger problem here is that your car originally had a computer controlled carb and distributor. There is no ignition advance mechanism in the original distributor, advance is all controlled by the computer. Replacing the carb removes several sensors that the ECU needs to operate, sending it into the "limp home" mode. This locks the distributor advance at a fixed advance. Did you replace the distributor with a non-computerized version when the carb and intake were swapped?
Does the car have actual gauges ? Or just the lights ?
If the light is flickering on at hot idle I would suspect low oil pressure more than anything. That would be the first thing I would check.
I think everyone is reading way too much into the OIL/CHOKE light thing. My money is on a loose choke wire that is intermittently grounding out and triggering the light. If the oil light were real, chances are the clattering lifters would corroborate it.
The oil/choke light started coming my 81 Delta 88 20+ years back. I checked the oil pressure with a mechanical gauge, it was just low enough to make the light flicker when hot with 5W30 at idle in gear. I ended up using GM engine flush, since the 307 engine had Ok power and used no oil. The 20 year Ford mechanic I apprenticed with, swore by the stuff. He eliminated cold piston slap in his 2.9 V6 Ranger. The flush raised oil pressure by a solid 5 psi and no more flickering light and ran many more miles, on top of the pile already on it. Throw an oil pressure gauge on it to confirm. If you your oil pressure is above 7 psi at hot idle in gear, look at the switch and wiring or ignore it.
Last edited by olds 307 and 403; August 2nd, 2022 at 05:36 PM.
Was this car originally a V6? The 307 cars used a hot air choke, not an electric one, and did not have the same OIL/CHOKE functions as the V6 cars. Also, the gold engine paint suggests that this is not an original 307 (which would have been black). Post a photo of the block casting number above the water pump.
The bigger problem here is that your car originally had a computer controlled carb and distributor. There is no ignition advance mechanism in the original distributor, advance is all controlled by the computer. Replacing the carb removes several sensors that the ECU needs to operate, sending it into the "limp home" mode. This locks the distributor advance at a fixed advance. Did you replace the distributor with a non-computerized version when the carb and intake were swapped?
as far as I know this is the original engine it was at 61000 when I got it last year it know sits at 62500 because I have to drive it daily do to my truck going out
The OEM carburetor had an electric choke that was wired up to work with the oil pressure switch. The carburetor that was installed has a manual choke. After the installation the electric choke wire was left disconnected. That is why the Oil/Choke light is on. You may have to change the oil pressure sending unit and modify the vehicles wiring to get the oil pressure light to function properly with out an electric choke.
To help you further please tell me if your car has a gauge cluster or indicator lights, how many terminals your pressure sending unit has, and a clear picture of the wiring to the current sending unit.
I included the OP/Choke diagram so I can early refer back to it.
Maybe Joe Padavano can help out here and let us know if there are OP sending units that are normally open and normally closed.
I am not mechanically stupid but not mechanically smart enough to read this chart lol the oil sending unit run back to the distributor cap as far as I can tell her are some pics
as far as I know this is the original engine it was at 61000 when I got it last year it know sits at 62500 because I have to drive it daily do to my truck going out
That's a 1968-76 350 block casting number, so it is definitely NOT the original engine. The VIN will tell you what engine it was born with.
The car only have a oil choke light no gauges for the oil
Originally Posted by Dynoking
The OEM carburetor had an electric choke that was wired up to work with the oil pressure switch. The carburetor that was installed has a manual choke. After the installation the electric choke wire was left disconnected. That is why the Oil/Choke light is on. You may have to change the oil pressure sending unit and modify the vehicles wiring to get the oil pressure light to function properly with out an electric choke.
To help you further please tell me if your car has a gauge cluster or indicator lights, how many terminals your pressure sending unit has, and a clear picture of the wiring to the current sending unit.
I included the OP/Choke diagram so I can early refer back to it.
Maybe Joe Padavano can help out here and let us know if there are OP sending units that are normally open and normally closed.
That's a 1968-76 350 block casting number, so it is definitely NOT the original engine. The VIN will tell you what engine it was born with.
Yes, not a 307. What is the large number by #1 and #8 cylinder on the heads? Check VIN pad on the block below the #1 cylinder for the year and application.
That's a 1968-76 350 block casting number, so it is definitely NOT the original engine. The VIN will tell you what engine it was born with.
I was told this car had two types of 307s the one with 5a head and the one i got with 7a heads the vin number confirmed it but im sure you know more than me judging from your responses
I was told this car had two types of 307s the one with 5a head and the one i got with 7a heads the vin number confirmed it but im sure you know more than me judging from your responses
Here is the VIN decoded. 5 litre engine.
VIN 1G4GM47Y8GP223874 Make BUICK Model Regal Year 1986 Drive Type - Style/Body 2-door sedan,hardtop,coupe Engine 5L Manufactured in PONTIAC, MICHIGAN, UNITED STATES (USA) Age 36 years
Please disconnect the connector at the OP switch. Post a picture of both the terminals on the switch and the switch side of the connector. Tell me how many wires are coming out of the connector. Can you post a picture of the choke assembly (Black cap) that was on the carburetor that you took off? While you are under the hood can you look for a single light blue wire with a black connecter that is not connected to anything near the right side valve cover. Post a picture if you can find it.
I was told this car had two types of 307s the one with 5a head and the one i got with 7a heads the vin number confirmed it but im sure you know more than me judging from your responses
Well, you were told wrong. In the 1986 model year, the only V8 available in the Regal was the VIN Y Olds 307 roller cam motor with the 7A heads. The "Y" in the eighth position of the VIN confirms that this car originally came with that motor. The block casting number that you posted also confirms that the motor currently in the car is an older Olds 350. Whoever told you that it's the original motor is lying to you. The next question is, how much did they muck up the wiring when they swapped the engine?
The wiring diagram I just downloaded from Shopkey for that vin number shows the V-8 oil pressure switch to be your typical normal 1 connector switch with a tan wire going to the instrument cluster. All of the stuff shown in the other diagram above is for the V-6 and Turbo V-6
The only strange thing is the diagram shows the switch to be NO (normally open) which I dont think is correct ?
Either way I am pretty sure the only thing that will make the light come on in this car is lack of oil pressure.
Last edited by BillK; August 3rd, 2022 at 06:09 AM.
Carl,
That engine should be perfectly fine with 10W30 oil 20w50 is old school for big bearing clearances and very hard running.
I really think what you need to do is take the oil sending unit out and hook up a mechanical oil pressure gauge to the engine and see what the oil pressure really is. That is the next logical troubleshooting step.
Carl,
That engine should be perfectly fine with 10W30 oil 20w50 is old school for big bearing clearances and very hard running.
I really think what you need to do is take the oil sending unit out and hook up a mechanical oil pressure gauge to the engine and see what the oil pressure really is. That is the next logical troubleshooting step.
thanks that has come up frequently I will see if my neighbor has one or purchase one from autozone on my off day and post results maybe even tonar after work
Yeah, you should be high enough with 20W50 to not turn on the light. What is your rpm in gear?
I don't know but I'm sure it is higher with the high performance intake unless edelbrock blew smoke up my butt lol in going to test the oil pressure and see what I get
I don't know but I'm sure it is higher with the high performance intake unless edelbrock blew smoke up my butt lol in going to test the oil pressure and see what I get
RPM in gear at a specific speed has nothing to do with the intake or anything else. It is purely a function of the rear tire diameter, rear axle ratio, and transmission gear that you are in (yeah, with a little added fudge factor for converter slippage). You can calculate this just by knowing those values.
August 1st, 2022, 03:09 PM
The wiring diagram is also for a V-6 Emissions sticker is not readable.
