Greetings to all...
I have appreciated all of the info I have received so far...but now a new issue has come up that has me absolutely stumped.
I took the vette out yesterday and drove it around for about 2 hrs....city and highway...just to blow out the spiders. ran great and lovin life.
Got it home into the garage and when I shut it off heard kind of a buzzing/clicking coming from the passenger side of the car. Went to start it back up and it idled horribly and oil pressure was registering about 4-6 lbs. If I push on the accelerator it runs fine...good oil pressure...about 50 lbs. I researched many threads as well as perusing the manual and everything pointed to the fuel oil pressure switch.
Long thread short, I have replaced both MAF relays, cleaned the MAF sensor, replaced the oil pressure sending unit, PVC valve, fuel pump and internal filter, fuel filter, and fuel pump relay. I have checked the FP fuse as well
Doing the exact same thing, but I did find a lot of little things to be corrected.
The car is throwing no codes ...except 12...and I have no idea what to look at now...
Any ideas?????

 

Test the injectors. I bet you have a stuck injector.

 

Code 12, by the way, is the code that indicates the start and stop of code displays. So you have no codes.

 

I forgot to mention that every time I did a cold start the motor would blow smoke like crazy.
Bad fuel or still think it's an injector?

Would I be looking at a whole bank or just one?
What is the best method for treating injectors?

By the way...thanks for the reply....

 

That could be a number of things.

The diaphragm in the fuel pressure regulator might have a hole in it. To check for that, remove the vacuum line from the fuel pressure regulator and look for fuel in the line.

You might have worn valve stem seals.

There might be a problem with the cold start injector. Try unplugging it and see how that affects things. Cranking time might be longer before the engine starts.

The ECM coolant temperature sensor on the front of the intake manifold might have a problem or there might be a bad connection. If the ECM sees an open in this circuit it will think the coolant temperature is -40° and will drastically enrichen the fuel mixture.

 

Smoke? What color? Or is it steam?

 

Black smoke...
The fuel is about 2,5 yrs. old and it has stabil and sea foam in it...about 1/2 tank....I was trying to just burn the fuel up then fill it with good stuff...until this problem arose. I thought maybe it was just the sea foam burning through the system.

 

Adding to the above, use your FP tester (have one?) to ensure it's proper, with pump running before start. during engine run, and if it holds when shutdown. Lots of threads on that, plus the FSM. Some of us tape it to the windshield for viewing ease.

Smell the dipstick for gasoline odor.

Don't allow this to go on too long as all that richness can ruin your CAT, or worse if the oil is diluting.

 

Not to mention the fuel filling the crankcase or a hydro-static lock that WILL bend con-rods. This will normally be caused from a bad FPR diaphragm letting fuel into the engine via the vacuum system. To check pull the vac hose off the FPR and check for fuel. If fuel is present do not attempt to start the car. You gotta a lot of work to do.

A bad injector can be dumping fuel full time when running and when the engine is off, dumps residual pressure/fuel into the manifold or if that valve is open, into the cylinder. Pull the plugs after she is cooled off and check for a wet or very oily plug/s. You gotta a lot of work to do.

Mind you this work isn't all that intensive but will use up a Saturday learning all the hoops and tricks to get the job done. Good news is you'll be and expert when all is finished.

 

Take a block of wood and a hammer and tap each injector several times firmly but carefully. This may free it up and saves a lot of time. It works sometimes, trust me. If it does get some Techron and use it.

 

Ok...pulled The plugs..all looked fine,checked the new fuel pump...comes on for 2 seconds then shuts off as it should,pulled the vacuum line from the fuel pressure regulator...no gas smell or fuel spill,tapped on the injectors.
I put a pressure gauge on the shrader valve and got the following readings:
Key on- 45# for 2 seconds
After 2 seconds-drops to 41 #
Let sit for 68 minutes- drop to 25#
Started engine and took to 1200rpm- bounces between 46 and 48#
Took foot off of throttle...instantly dies
When I started it oil pressure was about 78 lbs.
What the heck am I missing?

 

Oh ya...oil looks good...no fuel smell or discoloration or viscosity change

 

Just took the vacuum line off of the FPR and started the car...no fuel spitting out... Still at 42 psi at the fuel rail...

 

Just checked all of the injectors. All of them clicked when running a 9v battery test.
Cylinder#:
1-16.2 ohms...2.3 at the connector
3 -16.1 ohms...2.3 at connector
5 - 16.2 ohms...2.8 at connector
7 - 16.2 ohms...2.8 at connector
Cold start - 3.7 ohms...0.4 at connector
2 - 16.1 ohms...4.4 ohms at connector
4- 16.1 ohms...4.4 at connector
6 - 16.1 ohms... 4.3 ohms at connector
8- 16.2 ohms...4.3 ohms at connector
Car reeks of fuel at the exhaust when running..
Still pointing to the FPR?
All help is greatly appreciated

 

Not having a cold start injector car, I suspect that one is identical to the others and should test the same. An easy, cheap test is to unplug it and observe how it runs, especially when warmed up and the CS should be out of the ECM's picture, so to speak.

 

Based on your exam, all the fuel system components are functioning normally.
9th injector may be the problem, only one way to find out.
Pull the plug OR pull the injector and block off the hole

 

The cold start injector only functions during cranking.

It could be leaking fuel, so unplugging it may not prove anything.

 

However IF this injector remains open, it will continue to dump fuel after the start sequence.

Of course pulling the plug should have nothing to do with the problem....