I bought an 87 rx7 non turbo Im having some problems with it... Its running very rough and dies without constant throttle(sometimes). I pulled the plugs out and got some one to crank the engine, three of the holes didn't do much but got a little wet, the other(lower front) shot out jets of fuel, my question is are all the hole supposed to have fuel spraying out like that one, an if so are my injectors garbage?

Thanx for the help
EvilDalton

 

I'm not sure where to start on this one.

My first thought is to have the injectors professionally cleaned but I don't want to send you out to do that if the engine is blown.

Perform a compression test: http://www.aaroncake.net/rx-7/blown.htm

Now, unflood the engine totally (see FAQ).

How does the car run?

If poorly, try a new set of plugs.

If that doesn't do it and one rotor is obviously richer then the other (pull the plugs and post a picture...) then you may have a bad injector.

 

might be worth the effort to messure the resistance of the inectors to verify that they are within spec and also maybe litsen to them with a steathascope(spelling?) making sure they aren't sticking. sounds like one might be sticking open longer than it should flooding out that rotor.

 

Duh, of course! I forgot about the stethoscope which is always my first step when troubleshooting injectors. Don't know where my head was on that one.

An acceptable substitute can be a length of vacuum hose with a bolt shoved in the end. Hold the bolt against the injector and listen. However due to how far they are tucked under the manifold this can be very hard to do. Automotive stethoscopes are cheap and well worth the investment.

 

Thanks for the help I'm gonna check the injectors tommorow...

I changed the plugs and wires it runs a little better but still idles(after warming up) around 600Rpm and quite roughly. I also pulled my intake off to check out my throttle body and all of the butterfly valves were sticking so I freed them up using throttle body cleaner but after that I was unable to start my car(with intake still off) the car started a few times but didn't stay running, then the car got horribly flooded and I have to pull the plugs and cleaned them multiple times and the car would still not start...

However i found a place with injectors for $45 a piece(as apose to mazda for $242 a piece...) So im going to change them but when I looked I could only see 2 injectors. Is there only 2? or are the other two hidden? Im pretty sure I have one injector sticking or at least I hope so...

EvilDalton

 

There's no need to change the injectors unless there is something wrong. Get them cleaned, which will run about $20-$30 per injector.

There are 4 injectors on your car; two primary and two secondary. Review the fuel section of the FSM to learn more. The secondaries are on the upper intake, the primaries are on the middle iron.

 

Thanks for the help can you tell me what the resistance spec is for the injectors so I can compare them? And i have a service manual coming tommorow.

EvilDalton

 

Resistance will only tell you if the injector is electrically sound, which it most certainly will be. Around 2 ohms for 86-87.5, around 12 ohms for 87.5 - 91. But you'll likely find nothing electrical wrong with the injectors.

 

It was cold outside so I started the car before bringing it in and let it run an hour... After running for an hour the injector cleaner ran through the system and freed that sticking injector. Now the car runs perfectly every time I start it and does not hesitate at any Rpm!!! HOWEVER.....

I went to register it and the bastard that sold me the car for dirt cheap lied and now I need a Out of Province inspection... I am going to have to pay alot of money to repair it, which I will if it doesn't get ridiculious.

EvilDalton

 

Be warned, "injector cleaner" isn't really what you need. It may remove small deposits, but what I was referring to was an actual injector cleaning performed by an injection shop. The injectors are removed, sonically cleaned, run through a testing rig and then all rubber is replaced.

It can happen that an injector gets a bit sticky from disuse and then it frees up with a little runtime. Sounds like that's what happened to you. However if it stuck once, it will stick again. Get them cleaned.

 

Cool Thanks for the help I have alot of work to do now that I found out its needing an OOP...

 

i have an 87' also and it will sometimes flood out i think for no reason when it is sitting. when i go to start it, it cranks over but does not start. BUt the weird thing is that i can push start it and it starts but blows gas out the exhaust. What is the problem?

 

Typical flooding issue. It's leaking injectors, poor tune, low compression or a combination of all three.