Help! 1994 corvette coupe VIN P has no spark

[94blackvette]

I own a 1994 corvette VIN P and it has had a lot of problems in the past year. My opti spark when bad so I replaced it with a new AC DELCO opti. I was running for about a 6 months. About three days ago went to start it and it just turns over. I noticed that my water pump started to leak out of the weep hole and was leaking on my opti spark so I replaced it with a new ac delco. I am not getting any spark? What can I test or do to fix this problem???? Thanks.

 

[Toms007]

Are you getting any spark to the plugs? If so then are you sure you are getting fuel? Got to have these two things first.

Do you have a Fuel Pressure gauge? If so hook it up to the back of the fuel rail and crank the engine, I think it needs to have at least 41 PSI to fire the injectors. If the injectors don't fire then no fuel will be pumped into the cylinders.

Check all the basic stuff first.

 

[94blackvette]

I does not have spark at the plugs. I checked three spark plugs and nothing. I also checked to see if there was spark from the opti to the coil and there was nothing. Could this be a coil or a ecm?

 

[G Winter]

Opti spark plus water not good. The leaking water pump might have toasted your new opti.

Glenn

 

[Toms007]

Check all the wiring around the Opti. There is a coil and spark module.

 

[Paul Higg]

Tom, I have NO idea how you guys DO it! I mean, I can't even SEE in there even WITH a mirror. It sounds easy but it ain't. I mean I was so frustrated I had a Vette specialist do mine. Do you lift the motor up or something? How in the world do you get IN there?

 

[Toms007]

The spark module and coil are up pretty high, and I could feel with my hand. But you are right, I didn't say it would be easy.

 

[94blackvette]

All of my wires are on they way they are supposed to be. I check to see if anything had been pulled from the coil and everything checks out. What would you guys suggest I do first? I don't want to dump money in parts that are still working. Is there a way to test my coil or to see if my opti is communicating with my ECM? I tried to pull codes and there are no codes. I have fuel pressure and I bought a new battery about a week ago. I tested the injected with a node light and they seem to be working? I check the fuses. When I was installing my opti it found the spinned tooth marks and matched then up so I know it installed correctley because it will not go together right if those teeth are not alligned. Any suggestions before I buy a new coil?

 

[gmjunkie]

I does not have spark at the plugs. I checked three spark plugs and nothing. I also checked to see if there was spark from the opti to the coil and there was nothing. Could this be a coil or a ecm?

First you need a service manual,then you need to check and clean every Ground,Fuses and Wireing plug from the ECM to Ignition Module,Coil and Opti!!(Requires a Service Manual,Helper,Volt Ohm Meter and Test light!!)

Tom, I have NO idea how you guys DO it! I mean, I can't even SEE in there even WITH a mirror. It sounds easy but it ain't. I mean I was so frustrated I had a Vette specialist do mine. Do you lift the motor up or something? How in the world do you get IN there?

Nobody said it was easy!!!

Thats why we get the Big Bucks!
Witch usually converts to 3 skinned knuckles,$7.50 an hour and a Thanks!!!!

 

[John Robinson]

TPS

Before you get to far down the road with the big bucks try a few things and then let us know what happens.

First disconnect the TPS and try to start the car if it turns over and does not start then spary a small amount of carb cleaner or something like CRC into the throttle body while you have someone crank the engine over. If it runs for a short while reconnect the tps and try the same thing again

The tps tells the ecm how much fuel to deliver and if it goes bad then the ecm will not provide any fuel to the fuel rails. Oh and it won't code.

Also check this site for information on the tps and how to check it out.

Good Luck

 

[Hib Halverson]

If you are trying to solve this problem on a DIY basis, it's better to buy the factory service manual then perform the diagnosis in those books listed in Sec. 6E "Engine Controls Vin P" under "cranks but won't run".

In most cases, if you follow those diagnostic instructions, they'll lead you to a fix.

In addition, "gmjunkie's" advice about checking ground connections is very good advice.

 

[Hello]

how does your ignition coil tower look? Do you have a new wire from your opti to the ignition coil

 

[94blackvette]

I have no voltage on the A and D wires from my ignition module. I just the wires that go to the coil and they are fine. I even did a continuity check and they are good. What is a grounded coil circuit?

 

[94blackvette]

I still don't have spark. I don't know what to do? Would there be any codes? How do I check if the Ignition module is bad? Any help? Also where can I get a good service manual? I need electrical flow charts ect..

 

[Toms007]

Man, I'm sorry that I can't help you. But the best service manual is the Helms or FSM you can buy them from a number of sources, even directly from Helmsinc.com Here's a used set from ebay eBay Motors: 1994 Chevrolet Chevy Corvette Service Shop Manual Set (item 390023102583 end time Jan-16-09 16:12:14 PST)