TBI Troubleshooting

[HighFlyer]

Hello Everyone,

I am new to the site, so I am hoping that I can some help with the following issue on the my 82 Vette TBI's, Here it is. I have just finished restoring about 90% of the vehicle to original specs, including engine, tranny, and TBI's. I had the TBI restored by a shop in AZ, and had them shipped to the shop that is performing the restoration, however once they were installed the front TBI, when ignition is induced, even before the engine start, there is a huge amount of fuel coming out of it, and it continues even after the engine starts, the rear TBI is running fine. I called the shop that restored them, and they said that it could be the ECM, or the the prom in it. The TBI in question is being adjusted to .525 volts and all the electrical leading to it has been double and tripled checked. The shop that performed all the restoring is at awed with the issue, the ECM and prom have been replaced and the only items that have not been replaced is Fuel Pressure Regulator and the injector itself, but before I continue to throw parts at it, I was hoping someone had an idea, thanks in advance

 

[Hib Halverson]

Hello Everyone,

I am new to the site, so I am hoping that I can some help with the following issue on the my 82 Vette TBI's, Here it is. I have just finished restoring about 90% of the vehicle to original specs, including engine, tranny, and TBI's. I had the TBI restored by a shop in AZ, and had them shipped to the shop that is performing the restoration, however once they were installed the front TBI, when ignition is induced, even before the engine start, there is a huge amount of fuel coming out of it, and it continues even after the engine starts, the rear TBI is running fine. I called the shop that restored them, and they said that it could be the ECM, or the the prom in it. The TBI in question is being adjusted to .525 volts and all the electrical leading to it has been double and tripled checked. The shop that performed all the restoring is at awed with the issue, the ECM and prom have been replaced and the only items that have not been replaced is Fuel Pressure Regulator and the injector itself, but before I continue to throw parts at it, I was hoping someone had an idea, thanks in advance

I'd think it unlikely there was an ECM fault.

When you key-up but don't start, the fuel pump comes on for a few seconds but when the ECM doesn't sense rpm pulses, the pump shuts off. What you're likely seeing is a faulty injector on that TB. It's leaking, so as soon as you hit it with fuel pressure, fuel sprays.

You've got a 30 year old car. I'd replace both the injectors and the FPR.

 

[HighFlyer]

I'd think it unlikely there was an ECM fault.

When you key-up but don't start, the fuel pump comes on for a few seconds but when the ECM doesn't sense rpm pulses, the pump shuts off. What you're likely seeing is a faulty injector on that TB. It's leaking, so as soon as you hit it with fuel pressure, fuel sprays.

You've got a 30 year old car. I'd replace both the injectors and the FPR.

Thanks Hib,

That's what we figured, I have ordered both injectors and FPR's and will take it from. Thanks a bunch for your reply

 

[XLR8]

Just wanted to say WELCOME TO THE - HIGHFLYER!!!
Let us know how it turns out and share some pix when you're able.

We promise to be appropriately appreciative of your 82!

Jane Ann

 

[HighFlyer]

Just wanted to say WELCOME TO THE - HIGHFLYER!!!
Let us know how it turns out and share some pix when you're able.

We promise to be appropriately appreciative of your 82!

Jane Ann

Thanks, we'll do