Just changed injectors..Runs terrible!
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Joined: Oct 2004
Posts: 92
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From: Toms River NJ
Just changed injectors..Runs terrible!
I just got done changing my injectors. My original ones went bad and had a hard starting problem. I got some Ford 24# injectors off ebay with about 8,000 miles on them. It starts great now but it soungs as though it is missing and it is searching for an idle. It stalls once in a while too. There are no vacuum leaks and I had to change a couple of vacuum lines. I didn't touch the timing or anything like taht. My mirst question is would an adjustable fuel pressure regulator help? My second question is the vacuum line going to the for...Does it matter where it gets its vacuum source? I ran it directly from the rgeulator to the plenum.
Burning Brakes
Joined: Jun 2003
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From: smithtown ny
i don't know what you spent on them but i changed mine and i bought pink injecters from 5-o-motorsports for $180 i did what you did for my 91 and i wasted my money. you bought 24# injectors for one it's running rich. 2 you will need your chip redone the ecm will not correct the added fuel. contact ski-down-it for that. the injectors could be bad anyway you will have to test them. are you sure the injecters are all the way in the bores?? it only takes 1 to be bad.
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Joined: Oct 2004
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From: Toms River NJ
These are grey and light blue. They are definitely sitting in the bors. But when when I pulled one injector terminal off at a time, the car bogged a little. However, #1 made no change. I did notice that injector had a small crack on the tip. Would that be a factor? I know, stupid question, but I just want to make sure there may be something I am missing before pulling it all apart again.
Pro
Joined: Aug 2001
Posts: 617
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From: Loudon, TN
Originally Posted by 6spd
i don't know what you spent on them but i changed mine and i bought pink injecters from 5-o-motorsports for $180 i did what you did for my 91 and i wasted my money. you bought 24# injectors for one it's running rich. 2 you will need your chip redone the ecm will not correct the added fuel. contact ski-down-it for that. the injectors could be bad anyway you will have to test them. are you sure the injecters are all the way in the bores?? it only takes 1 to be bad.
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Drifting
Joined: Aug 2004
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From: Oceansaide CA
Get your DVM and test each one. I found my #5 to be bad, currently looking for a nice cheap set of 8, except all this BS that's flying around about pink/purple/ford etc makes me want to go OEM...
Pro
Joined: Dec 2001
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From: Oregon
Originally Posted by ClarenceT
Get your DVM and test each one. I found my #5 to be bad, currently looking for a nice cheap set of 8, except all this BS that's flying around about pink/purple/ford etc makes me want to go OEM...
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
you can put iin brand new injectors, but if you dislodge some crap while changing em, they'll clog instantly.
I put in 8 'flow tested and cleaned' injectors, and 2 of them didn't flow at all. i did the same test, by unplugging them one at a time like you did.
I then confirmed the flow by installing 1/2 of the fuel rail upside down and watching the spray pattern, or lack thereof.
I put in 8 'flow tested and cleaned' injectors, and 2 of them didn't flow at all. i did the same test, by unplugging them one at a time like you did.
I then confirmed the flow by installing 1/2 of the fuel rail upside down and watching the spray pattern, or lack thereof.
Summit sells a set of 8 new injectors for $230. 
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Originally Posted by ClarenceT
Get your DVM and test each one. I found my #5 to be bad, currently looking for a nice cheap set of 8, except all this BS that's flying around about pink/purple/ford etc makes me want to go OEM...
Team Owner
Joined: Jan 2003
Posts: 20,332
Likes: 262
From: Summerland B.C. Canada
Originally Posted by dirtnapp
I just got done changing my injectors. My original ones went bad and had a hard starting problem. I got some Ford 24# injectors off ebay with about 8,000 miles on them. It starts great now but it soungs as though it is missing and it is searching for an idle. It stalls once in a while too. There are no vacuum leaks and I had to change a couple of vacuum lines. I didn't touch the timing or anything like taht. My mirst question is would an adjustable fuel pressure regulator help? My second question is the vacuum line going to the for...Does it matter where it gets its vacuum source? I ran it directly from the rgeulator to the plenum.
Good Luck
Advanced
Joined: Jul 2004
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You can easily check the resistance of your injectors to find out if you have a bad one. Each injector should be 14-16 ohms. Lower resistance means shorted coil wires and that injector must be replaced. An impedance bridge will give you more information and will find an injector whose resistance is good, but has other problems (contact jfb for details). A crack on the plastic nose doesn't mean much as those pieces simply help the injector resist deposits on shutdown when the residual fuel on the tip evaporates leaving the heavy ends. BTW, I'm in Orange county New York and have a couple of good original injectors from my '91. You can have them if you'd like (closer than Canada - no offense Agent 86), but for what it's worth, I'd get a new style injector that doesn't let the electrics see the fuel (I got mine from Summit). GM had a problem with injectors in the late '80s/early '90s with acidic ethanol (or water) attacking the insulation on their injectors and causing shorts - I think that's what happened to mine. Newer injectors don't let the electrics touch the fuel.
