Hello guys and girls
I was able to get out of the house today and did some trouble shooting on the vette.
I started with the service engine light first. Found the bulb good, but bad connection with the bulb to holder. Just had to move small wires around on bulb and reinsert into holder and reinstall back into display center works now. Then I ran a code search. Found this codes. 44 lean exhaust 45 rich exhaust 54 Fuel pump circuit ( low voltage).
I recheck fuel pump regulator and did no find any fuel leaking on vacuum side.
Check egr valve with hand vac. pump sounds like it opened when I pull vac. and also sounds like it closes when I release vac. I attached a fuel pressure gauge with long hose to the fuel rail and taped it to the windshield.Stared engine and it seemed to run pretty good at cold start up with close to 40 psi. when I turned engine off the pressure dropped to zero in about 15 seconds. So I took it for a ride and seem to have good pressure over 40 but not more than 55psi at hard accel. No major missing and lots of power until engine temp started to go over 190 degree than started to missfire and Idle went away. Started to lope at stops and felt like it would die and then it did. Fuel pressure still holding at a little under 40 around 38psi but pressure drop when turned off much more quicker. Seem like a few injecters are no holding and raw fuel is filling cylinders. Get harder and harder to start after a few stops and can lots of fuel in exhaust. I am including a few pictures of old plugs pulled from engine after first trip home. I will post them my photos under black smoke

 

Ok here we go I got the vette into the garage and replaced the injectors with rebuilt bosch 3 from FIC. But still runs bad when it gets hot seem to run ok at first start up.
I have no new codes yet. Could this be the o2 sensors?

 

A bad 02 is definitely possible. You should check to see if the system is going into Closed Loop mode. I suspect the rich conditon may have killed the 02.

With a scanner you can see if the 02 is cycling properly. It should cycle it's voltage from about .100 to about .900 quickly and repeatedly.

Also, without a scanner you can check to see if the system is going Closed Loops by using a paper-clip or wire in the ALDL and monitoring how quickly the SES light flashes: Quick flashes indicates Open Loop and slow flashes indicate Closed Loop.

Either way, a scanner is always a good addition to your tool chest. It'll continue to be an asset and used over and over.

Jake

West Point ROCKS!

 

what terimals should I jump ok I fiqured it out seem like it is going in and out of closed to open not staying in closed. but sometime the closed mode has steady slow on and off flashes and then sometimes it comes on slow and big gap before the next one.

 

This is a strong indication that the fuel pressure regulator is bad. There is a simple way to check this. Pinch the return fuel line (rubber part on passenger side) and turn the key to on. If the fuel pressure does not drop quickly like you said it did before then you found the problem. The fuel pressure regulator is bad. I recommend replacing with a BBK unit. DONT get the Holley.

 

what are the terminals used on the alcl to monitor SES light while running to check for closed loop I used a&b With paper clip did I fry my ECM?

 

I FOUND THIS AND IT CLEARED ME UP ON EVERYTHING
Re: How to extract trouble codes for OBDI (up to '95)

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I thought I would add a little to this. You can go into "Field Service" mode by grounding the A&B pins and starting the engine. In this mode, the SES light will indicate whether the system is in Open or Closed loop. In Open Loop the SES light flashes two and one-half times per second. In Closed Loop the SES light flashes once per second. Also in Closed loop the light will stay OFF most of the time if the system is running Lean. It will stay ON most of the time if the system is running Rich. While in the Field service mode new codes cannot be stored and the closed loop timer is bypassed. Try not to drive the car due to the fact all timing advance is cancelled.
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Wow, never knew that.

 

I really want to get these problems behide me and cruise this vette around town. Burn the rear rubber off the wheels. I hope to feel the presents of my dad next to me. He would have like the Idea of me keeping this car in the family. Mike

 

here is my next attemp block off return line to the the tank and see if I can hold fuel pressure if not take out 9th fuel valve ( cold start valve) and see if it is leaking. If this is not leaking it must be the check valve in the fuel pump. At that point I well change out the fuel pump. I did a check on pressure regulator looks like a new diapham and no leak to the vacuum side. hope this gets better in time with the checks and not just replaceing parts. any help would be good.