engine running rough after installing new injectors

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rabeatyourmeato
Posts: 10
Joined: Sat Nov 07, 2009 7:57 am
Car: 1992 240sx s13

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i just installed new fuel injectors and it fixed my problem. i ran my car for bout two hours here and then came home. when i went to restart my car to go back out it runs rough. i have no vac leaks already fixed them, my compression is fine, and so are plugs and wires. when the cars on its almost pours gas from the exhaust like its getting too much gas. can anybody give me some advice on what to do next?


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moso
Posts: 801
Joined: Sat Jul 04, 2009 5:14 pm
Car: 89 240sx ka24de 5spd
90 240sx ka24de RIP

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chances are you broke an o-ring, its really common. unbolt and remove the fuel rail and the attached hardlines form the intake. leave your fuel lines connected. place a rag under your injectors and have a friend key on the car but dont crank it. when your fuel pump pre loads the system it will cause the leaky o ring to wiz gas all over your rag. remove and reinstall your injector with new rings. dont be supprised if you have to do it a few times, try using baby oil, vasoline, or just plain motor oil. WARNING- if you have keyed on and off your car a few times you can fill your cyl full of gas and possibly break something if you crank it. remove all your spark plugs, put a rag over the holes, and crank the car to expel any fluid.

rabeatyourmeato
Posts: 10
Joined: Sat Nov 07, 2009 7:57 am
Car: 1992 240sx s13

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yeah but they were brand new o rings. and would that cause just two cylinders not to fire?

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moso
Posts: 801
Joined: Sat Jul 04, 2009 5:14 pm
Car: 89 240sx ka24de 5spd
90 240sx ka24de RIP

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i went through 8 boxes of injector rings when i rebuilt my motor and ended up replacing 2 injectors. one because the plastic cap broke, the other because the lower o rings upper seat was disfigured and was causing the oring to not sit properly in the bucket. this is very very common. and it would cause any number of cylinders to not fire.

rabeatyourmeato
Posts: 10
Joined: Sat Nov 07, 2009 7:57 am
Car: 1992 240sx s13

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theres gota be a tool to take them injectors off. when i took my stock injectors out i broke everyone. haha. i just bought these 4 for like 150 bucks. i cant break these b****es.

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moso
Posts: 801
Joined: Sat Jul 04, 2009 5:14 pm
Car: 89 240sx ka24de 5spd
90 240sx ka24de RIP

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its common to distroy them taking them out. especally if thay are old. just be careful with the new ones. and there is a tool it just dosent work all that well.

rabeatyourmeato
Posts: 10
Joined: Sat Nov 07, 2009 7:57 am
Car: 1992 240sx s13

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well im goin to get a tool to take them off today. i was also told to check the connectors to see if they are pulsing. and that if they arent there just constantly shooting gas.

psmith
Posts: 214
Joined: Sun Mar 02, 2008 5:51 am
Car: 92' 240sx

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I just went through this the other day. I took a spare fuel rail with the injectors in and tested every solvent I had to try and simplify the process of injector removal. PB Blaster worked the best, hands down. Spray a little around the top of the injector. Let it soak. Spray again and start spinning the injector until it spins pretty easily. THEN start prying up in it. Pry with one hand, spray a little more with the other hand. Then it should slide right out. Clean up as much of the blaster as you can. I use vasoline on the new injector when installing it. Good luck!

rabeatyourmeato
Posts: 10
Joined: Sat Nov 07, 2009 7:57 am
Car: 1992 240sx s13

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yeah man i keep putting new ones on and right when i come back to my car to drive it after it sitting another o ring is broke. can i get better made o rings? like outa nylon or something?

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moso
Posts: 801
Joined: Sat Jul 04, 2009 5:14 pm
Car: 89 240sx ka24de 5spd
90 240sx ka24de RIP

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not that i know of but if you find some please let us know cause its always a pain in the a** like this. thats why its so popular to change to top feed injectors.

rabeatyourmeato
Posts: 10
Joined: Sat Nov 07, 2009 7:57 am
Car: 1992 240sx s13

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wen tto all my local auto stores and they didnt have the lower o rings that i needed. so i just went to lowes and got some o rings from the plumbing section. shes been runnin perfect all day.


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