Help! Damp Weather / Won't Start??

[Donne Trav]

Since early this past summer, and into this winter, my '94 won't start
after raining or most recently, after "wet" snow/rain mix? I've had the
wires, fuel regulater & pump replaced, along with, most recently, the
Opti (this summer), all within the past 1 1/2 to 3 years. The old COIL WIRE still remains though. After sitting a day or 2, then it cranks right up. Moisture must be getting in the system somewhere. Any thoughts would be greatly appreciated. Thanks

 

[Tuna]

Point a hair drier at the Opti for 30-45 minutes, then see if it starts. If it does, then moisture is likely in the Opti.

 

[boomdriver]

Since early this past summer, and into this winter, my '94 won't start
after raining or most recently, after "wet" snow/rain mix? I've had the
wires, fuel regulater & pump replaced, along with, most recently, the
Opti (this summer), all within the past 1 1/2 to 3 years. The old COIL WIRE still remains though. After sitting a day or 2, then it cranks right up. Moisture must be getting in the system somewhere. Any thoughts would be greatly appreciated. Thanks

Do you mean that it does not fire? or that the starter does not crank the motor?

When you turn the key, does the starter engage? or no?

 

[Donne Trav]

Do you mean that it does not fire? or that the starter does not crank the motor?

When you turn the key, does the starter engage? or no?

Oh yeah, the engine turns over like normal, continuously, just as it
would if you were out of gas. After a day or two, and the damp/wet
weather clears, it cranks right up, even in sub freezing temps.
Thanks "Boom"

 

[Schrade]

Are the SP wires in the looms?

What did you have goin' on last with your vette?

Moisture in the atmosphere will impede vaporization of fuel. I don't know what the threshhold is for firing, but if your injectors' spray pattern is borderline already, the threshhold could be crossed.

You done FP leakdown tests? You can observe spray pattern, but it's not a picnic... Pull the rails, with the injectors attached, get a glass jar under each injector, and jump the FP circuit. You don't have to spin the motor to do it...

 

[John Robinson]

There is a wire connector on the top of the opti that you can see from the right side of the engine. I had the same crank and not start condition as you describe. What I found was the problem was that on my 93 when I removed that connector the insides were corroded and it had moisture in it. I used my compressor to blow air on it and then I cleaned it with contact cleaner. After that I put some Vaseline on the rubber seal at the top of the wire connector and it fired right up. Time and heat are getting to the connectors on my car and I have had several issues with bad connectors bad grounds broken wires.

 

[Donne Trav]

There is a wire connector on the top of the opti that you can see from the right side of the engine. I had the same crank and not start condition as you describe. What I found was the problem was that on my 93 when I removed that connector the insides were corroded and it had moisture in it. I used my compressor to blow air on it and then I cleaned it with contact cleaner. After that I put some Vaseline on the rubber seal at the top of the wire connector and it fired right up. Time and heat are getting to the connectors on my car and I have had several issues with bad connectors bad grounds broken wires.

Thanks for your response. Are you talking about the COIL WIRE? If not, and I can see this wire connection
(poor eye sight), how difficult is it to get to -- remove and check out? I hope it doesn't involve removing
the parts I ended up removing just to get to the Opti when I replaced the wires a couple of years ago.
I hope that is the problem and it's an easy fix. Thanks so much.

 

[John Robinson]

Thanks for your response. If I can see this wire connection (poor eye sight), how
difficult is it to get to -- remove and check out? I hope it doesn't involve removing
the parts I ended up removing when I replaced the wires a couple of years ago.
I hope that is the problem and it's an easy fix. Thanks so much.

I have just taken some pictures but will have to send them later I have an appointment that I have to keep.

 

[John Robinson]

http://i285.photobucket.com/albums/ll72/John-68/Copy2ofOPTIconnector003.jpg

The connector just below the hose clamp

 

[Donne Trav]

http://i285.photobucket.com/albums/ll72/John-68/Copy2ofOPTIconnector003.jpg

The connector just below the hose clamp

Okay, but I need to look at the other end that goes to the Opti, right?

 

[John Robinson]

Okay, but I need to look at the other end that goes to the Opti, right?

That connector is plugged into the opti and the wires from it go to the ECM. I would guess that if that connection is shorted out then the ECM will not receive any input from it and therefore will not send a signal to the injectors for fuel to them. That is why I think you can crank but can not get it to fire because the ECM is not getting a signal that the opti is making spark to the plugs. I found it easiest to remove the plug from the TPS and the Air Intake to get more room and visibility to work on this connector. Be careful when you tug on the wires to get the connector off the opti socket. You don't want to compund your problems by breaking the wires.

Also I uses a long thin screwdriver to release the connector.

 

[boomdriver]

Okay, but I need to look at the other end that goes to the Opti, right?

Something that you might try just for grins....before taking stuff apart...

Sometimes under certain conditions the cold-start is harder, wet, cold...whatever.

What I have discovered and now do almost everytime I try to start mine after its rained or its been sitting a couple days, is to crank it for 1-2 seconds, turn key off, then crank a 2nd time and it fires instantly.
If I attempt to just keep cranking until it fires on the first try, that may be
5-10 seconds IF at all...For some reason that 1st brief attempt won;t fire it, but the 2nd try always will...instantly.

I'm not sure whats going on....I've tested fuel pressure at cold start and thats fine, (45 psi @ key on) and it holds it. But for some reason it just won;t fire easy that first rotation of the key when its stone cold. If its even semi warm, it fires off well.

 

[Donne Trav]

Thanks Boomdriver

Something that you might try just for grins....before taking stuff apart...

Sometimes under certain conditions the cold-start is harder, wet, cold...whatever.

What I have discovered and now do almost everytime I try to start mine after its rained or its been sitting a couple days, is to crank it for 1-2 seconds, turn key off, then crank a 2nd time and it fires instantly.
If I attempt to just keep cranking until it fires on the first try, that may be
5-10 seconds IF at all...For some reason that 1st brief attempt won;t fire it, but the 2nd try always will...instantly.

I'm not sure whats going on....I've tested fuel pressure at cold start and thats fine, (45 psi @ key on) and it holds it. But for some reason it just won;t fire easy that first rotation of the key when its stone cold. If its even semi warm, it fires off well.

Responding much appreciated. In DRY weather (very cold or hot), it
cranks right up. But, after it RAINS or a WET SNOW, for some odd reason, no start. It cranks just fine, but won't start. After the DAMPNESS leaves the air, usually a day or two, it cranks right up. I dread this happening away from home. I'll be using your starting technique in a few hours. Thanks Again