Stvictus

Hi:

I have a '91 FC N/A which has good compression and cold starts to factory setting (idles up with the proper cold start assist and then down to the right idle RPM). It drives and responds well. After running the engine for a while though, if you shut the engine down and then attempt to restart it, it takes several attempts to start up again.

Again, good compression. Also, RX-7 specialist looked into bearing failure and that wasn't it. Ran the car hard for a bit and used additives to try to expell any carbon buildup. Replaced the fuel filter which was nasty and that seemed to help for a while, but the problem has come back. The engine has 111,000 miles and new NGK spark plugs.

Would appreciated any ideas or leads on the issue. It's annoying because the car is otherwise in really good condition. . .

Thanks in advance.

misterstyx69

iTrader: (142)

If your fuel filter was nasty then think about what that filter did NOT catch.That crud can play with your start ups and cause hot start problems,leaking fuel into the internals and flooding.
I'd get the Injectors Cleaned and serviced.That means taking them off and sending then to a professional.
The Crap in a can is just that..so don't even bother buying that stuff.It's useless on engines such as this.
.You can send me the money if you'd like...and I'll send you back a Pic of me holding your money with a Big THUMBS UP!..lol!!...(it would be the same thing as using that ****!).
You can also check the water-thermo sensor and see if it is spec,as that is one thing that can cause hot starts..
But right now,I'm more towards the Injection cleaning.It's a common thing.

Edit:..I don't know why they would be checking Bearings,unless it was eating oil or shooting smoke.
Low Compression ..that is what I would have been looking for.
First thing you should check is compression on these engines.To rule out any internal concerns.

Stvictus

That's really helpful. I had the compression checked first thing. I've had a few RX-7s over the years and with the mileage, I needed to be sure the car had a bit more juice in the engine when I bought it. The car's in Florida and the first guy I saw didn't test the compression -- he just looked at the car and told me I'd need a rebuild at $4k. I took it to someone else who did the test and thought the engine itself was fine.

Would the best thing be to simply replace the fuel injectors at this point? I don't know if I will have time to take the car back to a rotary guy. Mazdatrix has new injectors for just under $300.

As background, the car just basically sits in a garage in Florida and I only get to drive it a couple of times a year at this point (until I move away from NYC and have a garage). I want to keep maintenance to a minimum and mostly keep it drivable as I can't do the service myself from here and have to rely on family to take it to places to have things done. I'm willing to deal with the cost of new injectors to save the hastle of removing and having someone professionally clean them...

Stvictus

Found a shop in the Orlando area with the proper equipment to clean fuel injectors. Going to give that a try and see what happens. Thanks again - will let you know the result!

Rot005

Try to check you fuel filter again you said it was nasty the first one may be a problem with you gas tank some sediments inside or water. Also check the compression with the car warm under normal temperature in all 3 faces of the rotors. Had the same problem with mine also a 91 vert when I bought it 118,00 miles ending up with a completed rebuilt, there are good rotary guys in the Orlando area.

misterstyx69

iTrader: (142)

If you take them off and send them out you save a fair chunk of money.
An Injector usually does not go bad.It just gets gummed up.

Guys on forum usually just send them out and get them done.They come back with a nice flow sheet of before and after,and new Orings and grommets to boot.

If you get NEW injectors,you are paying for unnecessary parts and you still need the new Orings and grommets to put them back in.

Look at a site called "witchunter" or try Injector-Rehab Fuel Injector Cleaning Services .This will give you a peak at what it entails.


NOTE: If you don't care about spending excess money then THIS is the Car for you.

This car also shows you to SHOP around if you are a little Budgetarily Challenged!

Stvictus

Thanks - I certainly don't mind saving money! I gave a speciality shop near where the car is currently located a call and they can do same day. They have the proper equipment and can do the full monty (pictures before and after of the injector flow, measurement of flow, etc.) and will put new o-rings on.

I'm crossing my fingers that this will help solve the problem but I won't know until just before Christmas when I'm in town to get this done.