Hi All,
I've been scouring the internet looking for a solution to my problem but I can't seem to figure it out. My 95 Corvette will not start... I've done all of the standard checks and I'm down to the injectors not firing. I am getting a strong signal to the injectors but they aren't pulsing when the car turns over. The car will run for a few seconds when I spray ether into the intake so I know it is getting spark.

Regardless, I changed the distributor, the spark plug wires, and the spark plugs. The fuel pump is working and I'm getting excellent fuel pressure with the key on and it's holding when I shut the car off. I brought the car to the dealer and had them install a brand new computer. I checked the connections to the distributor and they are all connected, I even disconnected and reconnected them. There was water in the lines and the injectors were gummed up. I pulled the fuel pump out and cleaned all of the gas, I then blew out the fuel lines. I pulled the fuel rail off and bench tested each fuel injector. I was able to get them freed up and ran some alcohol through the injectors. They all worked great. I got some fresh high octane gas in the car right now...

Do you think it's the fuel injection ground? Is that on the drivers side of the car on the bell housing with about 3 or 4 other wires?

Thanks in advance.

-Larry

 

Did you test the injector plugs with a noid light?do you have 12volts to the injectors?you maybe losing the ground signal.the ecm grounds the injectors to pulse them.the injector harness could be bad.ive seen this happen once

 

All most likely not all 8 injectors would fail at once and the car would run rough. sounds like a electrical problem. Check your voltage to the injector connections

 

Hi,
Thanks for getting back to me. I agree it has to be electrical because my light is not pulsing when I have the car turn over.

I don't have a meter to test if I am getting exactly 12 volts but the test light I have gets very bright. What I did to test this is disconnect the wire harness from the injector. Touch one end of the tester to the injector wire harness and ground the other part to somewhere on the engine block. The test light is very bright.

I'll buy a multimeter tomorrow so I can test voltage, I've been wanting one for years anyway...

-Larry

 

First, put your fuel pressure gauge on the shrader valve on the end of the right fuel rail. You should have 35-42 psi and it should hold up for a long time with the ignition turned off.
The signal to the injectors is a pulse to ground on the green/blk wire of each injector. The black wire on the injector goes to 12v. Get a noid light at a parts store and see if your injectors are being pulsed during cranking. If not, first check both injector fuses with an ohmeter, they see a lot better than you do. If you have a pulse and fuel pressure and still no starting, you have contaminated gasoline. Engines that start on starting fluid have no gasoline/air mix in the intake due to no gas, or no injecting.

 

Larry,
Even a cheap $5 multi-meter will work for you.
Check for +12 volts at the black wire of each injector connector or check continunity between all of them and then for +12V.

Check for continunity between the green/black wire and at the ECM connector. Take the connector off the ECM to get at the pin. Also disconnect the neg battery cable before doing this one.

As an owner of a '95, I have interest in this thread.

Lanny

 

Hi JFB,
In my previous posts I mentioned that I did all of the tests on fuel and fuel pressure. I put fresh high octane gas in there after cleaning the tank and blowing out the lines. I have a fuel pressure gauge and already checked that. it's good.

You did answer my question though about the green and black wires though because I think they ground out underneth the car on or around the bell housing correct???

-Larry

 

Lanny,
I didn't get a chance to do those checks last night because I have co-workers in from out of town and had to go to dinner. I will get the meter today and check this info out. Thanks everyone.

-Larry

 

No, neither injector wire goes to ground! The black injector wire has 12v on it with the ign sw in run. The black/grn wire goes to the ECM which pulses this wire to ground allowing the injector to spray for the duration of the pulse. The blk/grn wire goes to a fuse first and then to the ECM. The noid light will tell you if your injectors are being pulsed while you crank the engine. The fact that your engine runs on starter spray tells you that everything in your engine is working except it isn't getting fuel either because the injectors aren't pulsed or no fuel pressure or the gasoline is contaminated.

 

No codes? Could be VATS - it causes these symptoms I think.

 

If it were VATS, then the engine would not crank....I think??? Now I am second guessing myself....

Also, before doing any continunity checks....remove the negative battery cable. Otherwise you will most likely damage that $5 Multi-meter.

 

I have 12 volts at all injectors. I disconnected the negative cable. I'm looking at the ECM but can't determine where the green and black wire is.

-Larry

 

Ok, I'm going back out to check for the green and black wire again...

Thanks
Larry

 

Ok I have green and black wires at injectors for cyliders 2 and 4. Am I in the right place?

 

Just found a major coolant/antifreeze leak out of the right side of the block. I put water in and it's just pouring out from the right side about the starter. I can't see exactly where it's coming from...

-Larry

 

Sounds like one of the freeze plugs is leaking (I hope it's a freeze plug leaking rather then a cracked block) or maybe a heater hose going into the firewall.

 

Not sure. Unless someone else has a bright idea I'm going to pull out the starter tomorrow to see if I can see anything. I figured if it was a cracked block then I would have seen some water in the oil but there's none. This water pours out as fast as I can pour it in.

 

Each injector plug has two wires, one is black and the other is blk/grn stripe. The most significant test you can do is with a noid light, get one! See if the injector/s are being pulsed during cranking. If not, check both INJ fuses with an ohmeter. You can look at them too, but an ohmeter is best. If you have coolant coming out of the engine as fast as you are pouring it in, take care of that problem first! Good luck!

 

I think the green and black wire you are talking about is from earlier Corvettes (pre-1994). I don't have green and black wires at each injector. I also have another wire harness here for the same year car and it does not have green and black wires for each injector...

-Larry

 

True, but each wire goes to the same place as older C4's, one to 12v, one to an injector fuse and then to the ECM.