Oil light comes on while releasing clutch

[ForcedSHO]

Alright,
After getting the car up and running. I found that the car would shut off when the a/c was turned on. The oil light (far left) would go on as the alt. was conking out. Checked and replaced the alt. Turn a/c on now and it stays at 1,000rpm and may drop 100rpm and go back up.

The oil light would also and still does come on when I am releasing the clutch with not enough gas to shift or just letting it out in gear. Little confusing as to why the oil light keeps coming on. It seems to be coming on when the rpm's are dropping.

Thanks again,
Ed

 

[K-Dawg]

That light comes on when the oil pressure drops too low. Either the sending unit is failing, or your oil pressure is going dangerously low. The sending unit is located on the backside of the block above the oil pan, on the transaxle end. Bad rod bearings may be causing the oil pressure to drop.

FWIW, the light should come on when the RPMs get below 5-600 I believe.

 

[bigblock]

first at what rpm does the light flicker? what oil are you using? is you oil at the correct level? are there any extra engine noises? ie knocking, ticking? my car was doing this for awhile. it would flicker when the rpm dropped to 500 or less. turned out to be plugged cats and bad plug wires. this might be a case of rod bearings might not. you also might have a bad pressure switch. does the car have any other symptoms?

EDIT: k-dawg got it before me.

 

[ForcedSHO]

That light comes on when the oil pressure drops too low. Either the sending unit is failing, or your oil pressure is going dangerously low. The sending unit is located on the backside of the block above the oil pan, on the transaxle end. Bad rod bearings may be causing the oil pressure to drop.

FWIW, the light should come on when the RPMs get below 5-600 I believe.

I believe the oil light is coming on when the RPM"***** that 5-600rpm range. I'll have to check my Ford CD about diagnosing the Sending Unit and rod bearings

first at what rpm does the light flicker? what oil are you using? is you oil at the correct level? are there any extra engine noises? ie knocking, ticking? my car was doing this for awhile. it would flicker when the rpm dropped to 500 or less. turned out to be plugged cats and bad plug wires. this might be a case of rod bearings might not. you also might have a bad pressure switch. does the car have any other symptoms?

Oil and all fluids were all changed three weeks ago. Using synthetic oil. No extra noises that I can hear, no knocking or ticking. The car has had ShoShop ypipes on for about 55k miles. Wires seem to be ok. Otherwise no other real issues. Engine still feels strong

 

[Phoenix]

You dont have to seek for the infos on the rod bearings in your ford cds , Im not even sure if the rod bearings are in that list of possible issues.

The "weakest" link on a sho v6 are the rod bearings , and when that light flickers , its 99% of the time the rod bearings going out. Its a common and known issue.

If you wait too much , you will regret it. When you see the light , they are due NOW , not in 2 weeks.

 

[bigblock]

well it seems to be your in proper order. from what i understand its normal for the oil light to flicker when the rpms drop that low. the question is why is it dropping that low. like i said for me i had engine resistance causing it to bog down but your car seems to be all clean. not much else i can suggest. good luck

 

[tardboy21]

just keep it at 1k or higher when letting out the clutch. Are you just idleing it out? These motors have decent torque, but not that far down in the basement. It ain't a truck motor. Give a little more gas while letting out.

 

[sperold]

Did you have synthetic oil in it before this oil light thing? Did you put in a "winter grade" oil like 0w30 or lighter than usual in viscosity. Is it Quaker State?
The rod bearings sounds like a good guess, but you would expect some noise. I had a Mustang with bad bearings and you sure knew it by the sound, especially when you did an oil change and you started it without filling the new filter.
I have an 89 SHO with 320,000 kilometers, and it refuses to accept synthetic oil.... goes through it in no time flat, yet gets good consumption with regular premium oil.
Some people think that the filter brand makes a difference, are you using a Motorcraft FL-400S? I have read that this motor uses a high volume but low pressure oiling system, so the filter can be a problem with volume (if it is brand X).
It is times like this when you wish you had a real oil gauge in the car!

 

[AREA 91]

I believe the oil light is coming on when the RPM"***** that 5-600rpm range. I'll have to check my Ford CD about diagnosing the Sending Unit and rod bearings


Why are your rpm's in the 500-600 range? The factory idle is 900rpm.
You should NEVER have the rpm's that low.

Oil and all fluids were all changed three weeks ago. Using synthetic oil. No extra noises that I can hear, no knocking or ticking. The car has had ShoShop ypipes on for about 55k miles. Wires seem to be ok. Otherwise no other real issues. Engine still feels strong

Change the oil pressure sending unit. It's cheap.

 

[91PDXmocha]

im doing rod bearing right now... do yourself a favor and do them early.

 

[ForcedSHO]

how hard are the rod bearings to do?

 

[walser]

Did you have synthetic oil in it before this oil light thing? Did you put in a "winter grade" oil like 0w30 or lighter than usual in viscosity. Is it Quaker State?
QUOTE]
i just put some Q oil full synthetic in my car. and it seems like it is burning more oil now.. is quaker state known for this?

 

[sperold]

My 89 will go through any synthetic oil in record time. I have not bought Quaker S in a very long time, as I never had any luck with it (synthetic or regular).
I am a firm believer in Synthetic oil, but it didn't work out in my 89. I tried it twice, and both times my low oil light was on in a few weeks. One clue for oil consumption is you will find a trace of smudgy oil on your finger when you drag it across your back bumper cover, but that takes a long time to build up and one oil change interval would not be enough time for it to show up.

 

[jmpSHO]

You dont have to seek for the infos on the rod bearings in your ford cds , Im not even sure if the rod bearings are in that list of possible issues.

The "weakest" link on a sho v6 are the rod bearings , and when that light flickers , its 99% of the time the rod bearings going out. Its a common and known issue.

If you wait too much , you will regret it. When you see the light , they are due NOW , not in 2 weeks.

I'm sure the oil pressure switch fails more than RBs.

 

[Phoenix]

I'm sure the oil pressure switch fails more than RBs.

Then you need to use the search button and count how many rod bearings were changed versus failed oil switch.

Plus you'll have to count all the failed engines (V6) that people failed to comply the rod bearings rule. It would be safe to say that 95% of all failed V6 sho engine were caused by a spun bearing.

You will see the odds then.

 

[jmpSHO]

Then you need to use the search button and count how many rod bearings were changed versus failed oil switch.

Plus you'll have to count all the failed engines (V6) that people failed to comply the rod bearings rule. It would be safe to say that 95% of all failed V6 sho engine were caused by a spun bearing.

You will see the odds then.

Are you serious? I'm sure everyone that replaced there oil pressure switch didn't post about it. Out of all the rod bearing failures out there I'm sure alot had to do with owners either running there car low on oil or not changing there oil regularly or even using cheap oil.

 

[sperold]

I would start with the oil pressure sender first, thinking that it is easier, but I don't have any first hand experience on that. I have always thought that a mechanical gauge would be great, as well as the light. I would even settle for one that was only readable in the engine compartment with the hood up, just for situations like this one. I am afraid to drill a hole through the firewall for the mechanical gauge tubing, with my luck it would go through something expensive.
Do people still use plasigauge? I would give that a try on the rod bearings to see which rod / journal was the problem. We used to look for the grey coating on the bearing to see if there was any copper colour showing, the upper half wears first.

 

[ForcedSHO]

Haven't gotten the light for a few days. Running very well. I still haven't had a chance to look into the sending unit.

 

[JRA2000TL]

When you bog the engine like that, the oil light comes on; that's normal. I think it's the 500-600 rpm range. That's not good for the car. If that's the ONLY time it comes on then it should be fine. If it comes on any other time, look at the sending unit like they said 1st--cheaper and easier. If that doesn't fix it, then look at the rod bearings.

When I was learning to drive my SHO I wound up bogging it alot because I didn't want to ride the clutch and burn it up by over revving it. I've found out though that it's better to wind it up a little higher and slowly let out rather than bog the engine. You can rev it to about 1500-2k rpms and let it out. These engine run on lower oil pressure as it is and bogging it like that can **** it pretty quick I'd assume.

I'd say it's cheaper/easier to replace the clutch than the engine in these cars but ironically it's the other way around. Engines can be had cheap but alot of times you have to do cleanup work to them and the maintenance history of the engine is unknown whereas a new clutch you know will be good. Either replacement is a PITA though. Find the happy medium where you don't bog the engine or over rev and ride the clutch.

 

[ForcedSHO]

Thanks JRA and everyone else for the explanation. I have not had the light come one at all. Have been giving it a little more rev before moving.

Now the only problem is that my Low coolant light comes on in the morning. It's been below 50 everynight so far. Not on when I leave work though. Checked coolant and it's fine. Wondering if the coolant sensor needs some help.