leaky fuel injectors
Thread Starter
Instructor
Joined: Sep 2005
Posts: 145
Likes: 0
From: South Florida
leaky fuel injectors
I have read threads about checking for leaky fuel injectors and I believe I have that problem. When I pressure test, the gage goes up to a little over 40 but then it starts to go down. How long should it take to go down? Also how do I tell which injector is leaking? if I have a leak do I need to replace the fuel injector?
Thanks in advance for your help
Thanks in advance for your help
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
keep in mind that it COULD also be any of the connections within the fuel lines - or even the fuel pump/regulator itself not holding the pressure up.
If it leaks down over 24 hours or so I wouldn't worry, but if the needle moves in front of your eyes then I would try the injectors. Honestly, I am not aware of anyway to test the injectors short of removing the sparkplugs and continually priming the injectors (by turning on and off the key every few seconds). Disconnect the plugs to the injectors and then crank the engine a few times. The fuel that leaked out of the bad injectors should squirt/spray out of the sparkplug hole and reveal the reject.
Others may have an easier way - but that's the only thing that comes to mind right now. Also, you CAN test the resistance of the injectors with a voltmeter but I'd have to do a search for the specs on that one. Not sure if it works 100% of the time either.
If it leaks down over 24 hours or so I wouldn't worry, but if the needle moves in front of your eyes then I would try the injectors. Honestly, I am not aware of anyway to test the injectors short of removing the sparkplugs and continually priming the injectors (by turning on and off the key every few seconds). Disconnect the plugs to the injectors and then crank the engine a few times. The fuel that leaked out of the bad injectors should squirt/spray out of the sparkplug hole and reveal the reject.
Others may have an easier way - but that's the only thing that comes to mind right now. Also, you CAN test the resistance of the injectors with a voltmeter but I'd have to do a search for the specs on that one. Not sure if it works 100% of the time either.
Thread Starter
Instructor
Joined: Sep 2005
Posts: 145
Likes: 0
From: South Florida
thanks for the info.......I watched the needle start to go down slowly almost immeadiately. So if the injector or injectors are leaking do I need to replace them or is there a way to save them? Also, how can I check the regulator?
Melting Slicks
Joined: Apr 2002
Posts: 2,118
Likes: 0
From: St. Charles, MO Route 66 Corvette Club
88 Coupe: I suggest you remove the injectors and send them to Rich Jensen at Cruzin Performance. Rich will check them out and not charge you a fortune. His email address is: rich@cruzinperformance.com Your 88 came stock with Lucas injectors which are darn good. However, they could just need cleaning and Rich and do this along with flow testing them. Resistance is not usually a problem on Lucas injectors, but can be a real problem with the 89 to 91 models.
Once you know the condition of the injectors, you can better solve your problem. BTW, you can pull the injectors without pulling the runners. If you want info on this, send me an email to samlam@charte.net
SAM
Once you know the condition of the injectors, you can better solve your problem. BTW, you can pull the injectors without pulling the runners. If you want info on this, send me an email to samlam@charte.net
SAM
Last edited by Sam Lam; Jan 13, 2006 at 10:32 PM.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
You can check the injectors by lifting the fuel rail off with them still installled... then put paper underneath each and prime the system. With some creativity, you can also do a visual flow check of em... I have a pic somewhere of 1/2 of my rail on upside down with the injectors spraying into a box that I watch with a mirror while cranking. 
Just send em to Rich. The hard work is in removing and reinstallin them... The $90-100 for refurbishing them is the easy part. They'll come back looking and working like new.
Just send em to Rich. The hard work is in removing and reinstallin them... The $90-100 for refurbishing them is the easy part. They'll come back looking and working like new.
