C4 injector change issues
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Heel & Toe
Joined: Jan 2017
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C4 injector change issues
My father just passed down a 85 corvette and it needed injectors so i got a set of bosh injectors after i put them in the car will start up and act like the gas is to the floor then just die off as it starts to idle. The car would idle and run ok before the injector change. I was careful making sure to plug everything up right. Can anyone please help me private message or whatever thanks
Burning Brakes
Joined: Nov 2016
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From: Buchanan GA
I just changed the injectors in mine and had to cycle it a few times to get everything primed and all the air out of the fuel rail. Double check all your vacuum connections and test your fuel pressure.
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Look at your FPR too pull the vacuum line off and smell for fuel.
Last edited by antfarmer2; Feb 1, 2017 at 10:31 AM.
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Thread Starter
Heel & Toe
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Ok guys made progress tonight the fuel pressure is running 39-40 lbs. I change the spark plugs and checked all injectors they seem to be working fine. Got the car to idle but now its surging up and down. Throttle seems weird like if i push the pedal then let off it idles high even with my foot off the gas for a couple of seconds then back down to a surging idle.
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Heel & Toe
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Almost makes me think the computer isn't adjusted to the new injectors. The car had run for 10mins maybe. Also i could adjust the tps and make it sound alot better but like i said if i give it gas and let off the engine still gains rpm for a second after my foot is off the gas pedal. Anyone know where i should start?
Burning Brakes
Joined: Nov 2016
Posts: 761
Likes: 79
From: Buchanan GA
Almost makes me think the computer isn't adjusted to the new injectors. The car had run for 10mins maybe. Also i could adjust the tps and make it sound alot better but like i said if i give it gas and let off the engine still gains rpm for a second after my foot is off the gas pedal. Anyone know where i should start?
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I believe they are supposed to be 24lb. Sounds like your car is trying to use them. You could pulll the battery power off and let it reset then drive it 30 or so miles to relearn. But I would do this with the right injectors.
Team Owner
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From: Hartford WI
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Thread Starter
Heel & Toe
Joined: Jan 2017
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Hey guys i been thinking when i put the throttle body back on i noticed the gasket had a bad spot could that be causing (a vacuum leak) or any kind of problems with the idle surging? Please respond guy's and thanks to everyone helping me
Last edited by Tredzilla; Feb 2, 2017 at 06:51 PM.
Team Owner
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From: Hartford WI
Seriously? You also reuse your condoms? What possess you to use an old gasket?