fuel injector replacement starting issues

1996 CHEVROLET TAHOE
120,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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CHRIS BECKER
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My vehicle has 320,000 km on it and I just replaced the spider injector and upper manifold.
I went to start it after putting everything back and no go, not even a fire. I later decided to try to start it with putting some fuel right into the throttle and it fired right up and ran like a dream after the air intake pipe was put back on. Lots of power and a steady consistent run from the engine. After letting it sit and run for about twenty to thirty minutes I snugged it down to try and fire it up again and no fire again. Does not even give a little bit of a fire just turns over. Any ideas would be appreciated.
Aug 14, 2016 at 6:10 AM
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HMAC300
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check fuel pressure with a gauge shold be 60-66 psi if they do not have 60 psi they wont run.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
Aug 14, 2016 at 6:17 AM
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CHRIS BECKER
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It will run its just the start up. It wont even burp unless I put a little fuel in the throttle first. I bled the air out of the fuel system and it seems to have good pressure in the lines. Its just the start on its own without the initial boost of fuel in the beginning.
Aug 14, 2016 at 6:26 AM
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HMAC300
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read what I sent in first reply.
Aug 14, 2016 at 7:09 AM
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CHRIS BECKER
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It has good pressure. Are there any other problems that could arise after a spider injector replacement? My reader is not picking up any codes, but the EGR symbol is flashing.
Aug 14, 2016 at 11:01 AM
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STRAILER
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Did you use a oem (original equipment manufacturer) unit for the replacement?
Aug 14, 2016 at 11:45 AM
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CHRIS BECKER
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It was not a Chevrolet part, but the engine is running good when I start it using gas through the throttle body. It idles at around 700 rpm. Trying to start it on its own though it just turns over and does not even try to fire it seems.
Aug 14, 2016 at 11:53 AM
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STRAILER
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This only starter after installing the new injector assembly? The reason I ask is because we have seen this problem at the shop before and the after market injector for some reason will not let the injector start up, it is like it needs the engine running voltage to work, not engine cranking which is less.
Aug 14, 2016 at 12:24 PM
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CHRIS BECKER
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Yes, starting was no issue before but it ran badly and was throwing backfire and system to rich codes. Now the injector is in and it runs great, but wont start unless that initial boost of gas is put into the throttle body.
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Aug 14, 2016 at 12:49 PM
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STRAILER
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Let me know what happens when you change it out.
Aug 14, 2016 at 2:35 PM
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CHRIS BECKER
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I was really hoping it would not be the brand new part I bought that was faulty. I even went with the original design instead of the newer design.
Aug 14, 2016 at 2:48 PM
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HMAC300
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I do not go by the "pressure is good" what is the psi? like I asked in very first reply. get a gauge reading.
Aug 14, 2016 at 11:49 PM
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CHRIS BECKER
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Running pressure is around 47 prime pressure us only 40 seems to drop 10-15 psi in five minutes. Hoping it is just a clogged filter but preparing to have a fuel pump job on my hands.
Aug 18, 2016 at 7:17 AM
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STRAILER
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Yes is it sounds like it, you say it drops is this when the engine running or after the key is shut off?
Aug 18, 2016 at 8:45 AM
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HMAC300
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it needs 60 psi minimum to run and start. that has been your problem all along if the pump comes with a new harness about a foot long replace that as well as that model year they had problems with the harness and pump connections.
Aug 18, 2016 at 8:54 AM
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CHRIS BECKER
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It bleeds down after its been running. Its supposed to stay within five psi from what I have learned but it loses close to twenty when its shut down
Aug 18, 2016 at 11:43 AM
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HMAC300
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you have apump or blocked line problem and it's probably the pump it shouldn't bleed down more than 5-10 psi after shutting down with in 5 minutes...replace the pump
Aug 18, 2016 at 10:57 PM
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