89 injector leak down
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Corvette Enthusiast
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From: So. Cal.
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89 injector leak down
The current injectors are from autozone. Bought them before I was a member here and now know better.
They leak down to 15 lbs after 50 minutes. Havent ohmed them yet.
I have several things I want to do, and getting close to starting them, depending on my injectors. The car runs fine. Hard starting a little in the morning.
Thanks in advance
Corvette Mike
They leak down to 15 lbs after 50 minutes. Havent ohmed them yet.
I have several things I want to do, and getting close to starting them, depending on my injectors. The car runs fine. Hard starting a little in the morning.
Thanks in advance
Corvette Mike
Last edited by CorvetteMike2024; May 1, 2009 at 08:46 PM.
Thread Starter
Corvette Enthusiast
Joined: Oct 2007
Posts: 6,797
Likes: 2,721
From: So. Cal.
2025 C7 of the Year Finalist- Unmodified
2024 C7 of the Year Finalist - Unmodified
2023 C7 of the Year Finalist - Unmodified
vette
My car runs fine right now. I am going to be polishing all the TPI stuff and wanted to know about how much leak down is acceptable before I start the project.
Thread Starter
Corvette Enthusiast
Joined: Oct 2007
Posts: 6,797
Likes: 2,721
From: So. Cal.
2025 C7 of the Year Finalist- Unmodified
2024 C7 of the Year Finalist - Unmodified
2023 C7 of the Year Finalist - Unmodified
Agent 86
Hey Agent 86, Thanks, How's the construction project comming along?
Team Owner
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From: Summerland B.C. Canada
Melting Slicks
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From: St. Charles, MO Route 66 Corvette Club
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Safety Car
Joined: Jan 2008
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From: Vero Beach Florida
Hey Mike leak down sounds ok however you will have it all apart for detailing so if you have the extra cash you could always swap them out for the Bosch lll's. Other then piece of mind no real reason to / remeber if it ain't broke don't fix it. Let us know how the polishing is doing.
Le Mans Master
Joined: Dec 2000
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From: San Diego, Ca
Leakdown/balance is pressurizing the rail and then measuring the drop after energizing an injector for 5 ms. You can buy a tool - about 80 Bucks - to do the energizing, but reading the drop on most pressure gages is difficult because the graduations are too small to read. Enterprising souls have pulled the rail, left the injectors attached and juryrigged a graduated beaker below each injector so they could measure the flow. Doing this hot and cold would be the ultimate test. This seems like a lot of effort when you could simply replace or have yours cleaned and rebuilt (which is what you're going to do anyway assuming you confirm a problem). PS - Years ago, I bought the tool, tested mine and from what I could read, there wasn't a problem. Replacing the injectors however, cured a cold hardstart that it had since new.
