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I installed in 95 a new crate LT-1 engine in my street rod. Vette engine, with fuel leads on RIGHT side of engine.


Today it didn't start, starter spun the engine fine, but no sounds of it trying to start. I pulled a plug and no signs of fuel, plug NOT wet.

I'm NOT electrical, but very hands on, I pulled the cover in the trunk to expose the tank pump. What's the best way to see if power is getting to the pump? Painless wire horness, fuse for fuel pump looks good.

If I understand correct, when key is in start mode, pump works for 2- 3 seconds then shuts down if no oil pressure.

Comments most welcome.

Thanks,
Smithbrother
 

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Should be able to hear pump pressurize line when you turn key to on, not start-yet. Turn key back to off, back to on, back off, back to on....then try to start. My LT1 had weakness issue with pump and following that sequence at least got me started. I ultimately had to replace fuel pump. Nonetheless, with car door open, the first key turn to on, you should be able to hear pump pressurize fuel line. You don’t hear it...then pump isn’t weak, it’s toast (unless fuse or broken wire).


Priming fuel pump with on and off will also eventually melt your ignition switch...ask me how I know.


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I'm not familiar with the painless wiring harness. But if you are using the stock 95 computer, here is what happens.

First of all, when you turn key on, the security light comes on for a few seconds and goes out. This indicates that vats security is working. If security light stays on, fuel injectors will not open.

Also if you have a code 16 for low res opti signal not present, neither fuel pump or fuel injectors will work. If you have icm codes 41 or 42, injectors will not open.

So, if you still have vats security system enabled, you need to make sure it's still working.

You need to check for codes to see if you have dtc 16, 41, or 42. The only 100% way of checking low res signal, if you have dtc 16, is with an oscilloscope. You can buy a PC based scope for around $70 on ebay, amazon, etc.

Also if you have dtc 41 or 42, the fuel injector enable signal will be absent. Same with vats security problem. The scope will show you if fuel enable signal is present.

All this is dependent on you having a stock 94 or 95 pcm, an aldl connector port, vats security present.
 

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Should be able to hear pump pressurize line when you turn key to on, not start-yet. Turn key back to off, back to on, back off, back to on....then try to start. My LT1 had weakness issue with pump and following that sequence at least got me started. I ultimately had to replace fuel pump. Nonetheless, with car door open, the first key turn to on, you should be able to hear pump pressurize fuel line. You don’t hear it...then pump isn’t weak, it’s toast (unless fuse or broken wire).


Priming fuel pump with on and off will also eventually melt your ignition switch...ask me how I know.


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Thank You, been out of town, so hoping to get back to it tomorrow.

I don't know the year of the computer, it was part of the wire harness I bought from Street performance. It could very well be a 95 computer since Street Performance knew the engine was a 95.
 

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Pump should run for a few seconds just turning key to 'on'.
If not running during that time(the fuel pump) what does the wiring harness use as as a safety in rhe event of an accident to shut the pump off. Most use a pressure switch activated by oil pressure. Check there ?
 

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Pump should run for a few seconds just turning key to 'on'.
If not running during that time(the fuel pump) what does the wiring harness use as as a safety in rhe event of an accident to shut the pump off. Most use a pressure switch activated by oil pressure. Check there ?
Lack of oil pressure shuts my fuel pump off after a few seconds. I'm still out of town, so can't do more for a few days, THANK YOU.
Dale
 

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I would check the shrader valve at the back of the engine for fuel pressure. I personally just bought a kit at Harbor freight for $30 for my 94' and twists right on and can read fuel pressure to the rails.
 
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