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Hoping someone might be able to give me some advice as to what's wrong with my 96 SS. When starting the car and putting it into gear the oil pressure light comes on and it occasionally stalls. When driving I have no issues while moving. When I come to a stop the oil light comes on and it sometimes stalls. It does start back up with some difficulty. When putting it into gear the RPM drops to around 500 and then the fuel light comes one. As soon as I feather the gas the light will go away. When turning the wheel all the way in gear the car will stall/stutter with the oil light on (when getting into my garage). I have had the home base delete, the fuel pump, oil cooler lines, oil switch sensor, temp sensors and some minor things recently done. The issues with the car started after having these parts replaced/work done. Mechanic says the throttle body, idle air control and oil pump look good but haven't been changed. 111,000 miles, mechanic says the plugs and wires look good. Would a tune up help? Anyone have any suggestions as to what could be wrong or what I should check? Thank you!
 

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..... Mechanic says the .....oil pump look good ....





....Would a tune up help? Anyone have any suggestions as to what could be wrong or what I should check? Thank you!

I hope you mean the mech thinks the "above idle" oil pressure is ok. No way to pass judgement on the pump unless the pan was dropped. And of course a tune up will help. Regardless of miles all the parts normally associated with a tuneup are 25 years old and need replacing. But I would hold off throwing more variables in until solving the current problem.



Same as you, I strongly suspect something that is connected with the work you had done.
-home base delete, = pot. incorrect R&R the MAF. Even installed backwards.
-the fuel pump, = dislodged gunk and you need a new filter. Or fubared the pump flexline and getting only part flow volume
-oil cooler lines, oil switch sensor = damaged the connector or wiring. Wrong part. Or installed wrong.
-temp sensors, worn or broke ETC connector or wiring. It's relatively common on our car.
-some minor things recently done. What exactly were they? Look nearby all of them for fubared surrounding upset parts or cut or pulled wiring or hoses.
Search for procedure to do a static and running fuel pressure test. You'll need a gauge.

Up to you, but would resist going back to that mech. Any caught and corrected work may be claimed to be a different cause, and you're basically on the clock while he throws more parts at it.

It will be helpful to know a.) what prompted all this work in the first place? and b.) was it you who specifically ordered each item replaced or did you leave it all to the mech.?
 

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I bought the car about 3 weeks ago, and the old owner told me it was sitting for a year. I drove it 100 miles back to my area in Arizona and dropped it off at my mechanic for inspection. He has never done a poor job before, but I have never brought him a 96 SS before. Having said that, he has owned one, and has worked on them in the past. He looked it over and recommended the replacements mentioned above be done along with new seals, gaskets, etc because, ironically, the car was leaking oil when I bought it. I had been searching in other posts and saw that potential problems could be the throttle body, idle air control valve, TPS, oil pump. I bought all these parts before posting, and simply let my mechanic know that I want to be installed. I even grabbed a radiator because he did a flush, but the coolant in the reservoir looks muddy, probably from the car sitting so long. What should I be telling this mechanic, or another one to check? Do you know where I might look for any mechanic recommendations in the Phoenix, AZ area? Thank you
 

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Hook the car up and see what it wants to tell you. Even if there is no CEL now, there may be a code stored. If not, at the very least you can look at the data and decode any underlying issues much easier than doing it by feel. In addition to what 96 Black suggested above, if the car had fuel in the system and sat for a year, your injectors are more than likely clogged up with gunk. Same with your fuel filter and possibly even the sock on the in-tank pump. The fact that your mechanic never suggested dropping the tank, blowing out the lines and servicing the injectors makes me suspicious of the person's skills.
 

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.... if the car had fuel in the system and sat for a year, your injectors are more than likely clogged up with gunk. Same with your fuel filter and possibly even the sock on the in-tank pump. .....

OP mentioned a lot of work and new fuel pump is buried in there.





I bought the car about 3 weeks ago, and the old owner told me it was sitting for a year. I drove it 100 miles back to my area in Arizona and dropped it off at my mechanic for inspection. ......
If I'm reading this right the car did ok on the ride back, but you pulled the trigger on all this work more or less as PM???? My approach is is usually get something new back to the safety of my house and attend to 1st priority stuff - filters, oil change, undercarriage check, brakes..... And then start a shopping list of suspect issues as it gets driven around a bit. Not preaching, but wondering if we're getting the right picture.

Something is letting the idle get too low, and then the self-preservation sensors and circuits are kicking in to stall it before meltdown.



You DEFINITELY should take advantage of searching on here. There was just recently an issue with stallouts connected with the oil pressure or level sensor on the oil pan, which I think you said got changed.



Of course if you just didn't mention the car was running crappy even on tthat 100-mile drive home and the the reason the car sat for a year was the same problem you're having now, well then that's a whole 'nother story. So you see so much goes into diagnosis than just a couple symptoms. You set out pretty decent background, but more of the above could sure help de-confuse things. Regrettably with so many things done at once makes finding the gremlin harder. In the absence of any better idea it's just time to hit the FSM and all its diagnostic charts.


There might be a point where you want to pay to get it hooked to a fancy complete garage scanner that reads errthing running realtime?
 

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OP

Being a "point & pay" guy with a 23 year old car is going to hit your wallet hard.

Do yourself a favor and buy a OBD2 scan tool. Several around and generally about $100+ for the ones that also show live data.

Buy a FP gauge with a Schrader valve end (Hypertech)

Get a IR temp gun for $20

This problem of stalling and low oil pressure "after" the fuel pump and oil pressure sensor were replaced.....checking fuel pressure with a gauge and inspecting the oil pressure sensor (wiring, sensor type) would be in order.

If the OP sensor reads 5 psi or less it will shut off fuel in attempt to preserve motor. The sensor itself may be the wrong one or messed up

...or it is working correct and you in fact have low oil pressure due to worn bearings...

low idle, especially when turning wheel at a stop, often means the OAC valve is bad. It could just need cleaning with throttle body cleaner. You need to remove throttle body to access the IAC. If the coolant hose still runs through the TB than this would be a good time to bypass it. You will need to bleed the cooling system if you do this but won't have to inn future if removing the throttle body for cleaning

car sitting for a long time the fuel, especially with ethanol, will gum up parts. Especially injectors. They can be serviced cheaper than buying new ones. I use www.cruzinperformance.com. IIRC it is about $15 per injector. Send all 8

Replace fuel filter

The FP gauge has a hose on it so you can tape the gauge to windshield. FP should be 42/5 at idle with vac line disconnected and plugged and drop about 5-7 lbs with vac line attached. It should rise to 42-45 PSI on acceleration. It should never decline while sustaining WOT. This is why you tape it to windshield so you can monitor it during deiving conditions and when the car idle low when stopped
 

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Discussion Starter #7
.... if the car had fuel in the system and sat for a year, your injectors are more than likely clogged up with gunk. Same with your fuel filter and possibly even the sock on the in-tank pump. .....

OP mentioned a lot of work and new fuel pump is buried in there.





I bought the car about 3 weeks ago, and the old owner told me it was sitting for a year. I drove it 100 miles back to my area in Arizona and dropped it off at my mechanic for inspection. ......
If I'm reading this right the car did ok on the ride back, but you pulled the trigger on all this work more or less as PM???? My approach is is usually get something new back to the safety of my house and attend to 1st priority stuff - filters, oil change, undercarriage check, brakes..... And then start a shopping list of suspect issues as it gets driven around a bit. Not preaching, but wondering if we're getting the right picture.

Something is letting the idle get too low, and then the self-preservation sensors and circuits are kicking in to stall it before meltdown.



You DEFINITELY should take advantage of searching on here. There was just recently an issue with stallouts connected with the oil pressure or level sensor on the oil pan, which I think you said got changed.



Of course if you just didn't mention the car was running crappy even on tthat 100-mile drive home and the the reason the car sat for a year was the same problem you're having now, well then that's a whole 'nother story. So you see so much goes into diagnosis than just a couple symptoms. You set out pretty decent background, but more of the above could sure help de-confuse things. Regrettably with so many things done at once makes finding the gremlin harder. In the absence of any better idea it's just time to hit the FSM and all its diagnostic charts.


There might be a point where you want to pay to get it hooked to a fancy complete garage scanner that reads errthing running realtime?


The mechanic hooked it up to a diagnostic scanner, and it has no active or stored codes. The machine he used can control anything and everything in real time and can scan it as well in real time. Nothing at all. Everything is running right according to the car's computer which is even more frustrating. I will be bringing it back this weekend to check now that the oil light is on, maybe it will throw a code or something.

I appreciate all the advice. I'm new to all this stuff but a quick learner.
 

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Everyone has their favorite

"If the OP sensor reads 5 psi or less it will shut off fuel in attempt to preserve motor. The sensor itself may be the wrong one or messed up"

This is FALSE !!!!!!

The 94-96 PCM does not have a clue what the oil pressure is !!!

The 94-95 does have a oil pressure switch that parallels the relay , but the relay stays energized by the PCM as long as it sees rpm, not matter what is going on with the oil pressure
The 96, doesn't even have that oil pressure switch .

If the PCM sees rpm, Connector C1 7 circuit 465 is powered energizing fuel pump relay terminal E9

The "my oil light came on, then the engine stalled" is typically backwards.
More like " my engine was stalling and the rpm was so low, the oil pressure lamp came on"

The only time low oil pressure lamp coming on would stop the engine is if the relay , ( on a 94-95) is not working already.
This would also show up as the fuel pump not cycling with key on and extended crank times because the pump would not run until you had oil pressure.
 

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"If the OP sensor reads 5 psi or less it will shut off fuel in attempt to preserve motor. The sensor itself may be the wrong one or messed up"

This is FALSE !!!!!!

The 94-96 PCM does not have a clue what the oil pressure is !!!

The 94-95 does have a oil pressure switch that parallels the relay , but the relay stays energized by the PCM as long as it sees rpm, not matter what is going on with the oil pressure
The 96, doesn't even have that oil pressure switch .
Well darn Gerry...my bad if I got this wrong. FWIW my 96 does have a oil pressure sender on top. rear, of block

Back when you & I were talking about gauges I knew that would be a location to "T" a mechanical gauge sender but I chose to use the port above oil filter adapter for that and left the stock dash sender as is.

My bad if I posted wrong 411, I thought the sender, if OP got below 5 PSI, signaled PCM to shut fuel off but if that is not the case thanks for clarifying.
 

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if the relay fails you will still be able to start once pressure gets above 5 psi. i believe it also takes some load off the relay contacts.
 

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::snip::
....., oil switch sensor, ....!
Well color me confused too. From the wording I thought that referred to the switch in the oil pan.

At least I (finally) learned something about it, - pulled from another forum:
[" The PCM only checks oil level right after startup (and after the engine has been off for a little bit). It does not keep monitoring oil level while driving."]

And from this it apparently has no control to shut down while driving. But sounds like it either will not permit start-up or just show a light if reading low:
https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-low-oil-level-sensor


All the above just to let OP know he don't have to change it ;)
 

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I can say that on my 95, it started and ran just fine with the factory pressure sender disconnected. It did store a code though.
 

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Reeeeaally ??
What code?
I don't recall the exact code - it was some weird code(s) about a reading being out of norm. I'll disconnect it once I get my gauges re-installed and post the code. There were two.
 

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i remember 15 years ago trying to add a 3 wire o2 to my '89 caprice either taping into the fuel pump relay coil voltage or fuel pump supply and got code 54. I think ending up popping something in the ECU and had to replace it. you could also be getting code 44 (lean) because your fuel pumping is running at a lower voltage from what I mentioned above.
 

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Hi SamSS, from post #7 sounds like mech verified fuel pressure is okay, if not get that done.

Playing keyboard cowboy, and i hope i'm wrong but my money is on this....

...or it is working correct and you in fact have low oil pressure due to worn bearings...

Cuz happened to me... oil light comes on at red lights and then goes off when i take off.

Good Luck.
-ALF out....
 

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If you are going to get a reman engine, get the Corvette engine with aluminum heads. Price is not much more, and with a tune, you get more power.
 

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Hi, if you go that route of getting a F-body or Y-body motor in your B-body, PLEASE report back how it feels.

From all i've read the cam is so different and made for cars about 1000 pounds lighter, it may feel slower. Curious about real world results though.
Trading Torque for HP basically.
Thank you.

EDIT:
just so you know i am on my 4th motor average 100K each, over 300K now :),
for the price of that jegs motor i get used cappy motor and warranty and it gets installed.

If doing it yourself, then jegs sounds like FUN !
 
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