ComBoost

Hello all, I'm kinda new to rotaries and RX7s and i'm running into a problem.

Turbo2 Motor with a bigger turbo/halfbridge port.

Whenever i start my car it wont hold idle on its own, if i keep it running by giving it gas it runs a bit harsh while smoking like crazy and starting to bog down due to flooding is my guess. I've checked compression, spark, and fuel. In doing so after pulling the plugs after each go at it i find that my rear rotor plugs are usually soaked each time and the front rotor plugs are fine.

Does this mean I'm getting too much fuel in my rear rotor from a leaky injector or one stuck wide open? if so does that mean do a leak-down test?

Thanks, I appreciate the help.

RotaryRocket88

iTrader: (7)

What was the result of the compression test; specifically on the rear rotor? If the plugs are wet, it's a good bet that there is no combustion taking place, which would result from a lack of compression.

ComBoost

They were all nice even bounces. I pulled the uim and tested the primary rail to test for leak and they weren't the problem. I've already got the second rail off just haven't strapped it down and tested it yet, I will in the morning and post up results. Hopefully that will be the problem.

Thanks for the reply.

Aaron Cake

iTrader: (1)

What EMS system are you running? What injectors? Fuel pump?

Bridgeports need a LOT of fuel. It may be leaning out just after the afterstart enrichment stops. Do you have a wideband?

ComBoost

Nope no wideband. Getting one very soon though.

So after testing the secondaries there were no leaks... wth?

I put everything back together then ran it again.. still the same problem though it It had run fine before.

I pulled the plugs once again and realized the trailings were soaked leadings were fine?

So i tested the spark with new plugs and tried again. With the same result. Trailings still soaked. Car still dies.

I'm not sure what I should do now.
Replies Appreciated.
Thanks.

86RotaryRx7

my 86 does the same thing. non-turbo

ComBoost

Yeah. I'm not sure. I'm fairly new to rotaries. I'm not sure what to try next.

Aaron Cake

iTrader: (1)

Answer my questions and I may be able to help.

What ECU?

Injector sizes?

ComBoost

I'm Sorry. Everything is stock. Stock ECU and stock injectors(orange right? 550?)

I do need to upgrade a lot and tune, but it ran before. I didn't drive it really at all though. It's just been a work in progress.

It was an ordered swap and it accidently came with those goodies.

Thanks.

Aaron Cake

iTrader: (1)

There's your problem.

The car will never run like this. Ever. You may be able to get it to start, maybe idle a bit when the engine is cold and the ECU is hammering fuel in, but that's about all. Swapping to larger injectors all around (720CC) should get it running, but it will run poorly.

You need a full standalone ECU to run a bridgeported engine.

Your bridgeport requires 50% more fuel just to idle then a stock port.

ComBoost

Dang. Well i don't really have the funds to do any of that as of now.

Is it odd that it was running before and i was able to drive it?

It all seemed to happen after i put in my t2 afm, so i figured that was the problem so i swapped my old one back in but it still had the problem.

I did the same process with the boost sensor to check as well (even though it was doing fine with the new one.)

I don't really want to sell the car but I also need something I can drive.
Maybe i'll have to find a cheap dd or something.

Thanks for your help man, I appreciate it.

Aaron Cake

iTrader: (1)

It was running before on a bridgeport with a stock fuel system? Probably, but certainly not well.

For the record, any turbo upgrade on an RX-7 requires a standalone and a fuel system to support it. Most anything on the stock turbo can be accomplished with the stock ECU but once you get into turbo upgrades and porting (especially bridgeporting) then you need a standalone.

ComBoost

Yeah it was running but crappy.

Ah i understand. Well it wasn't supposed to come with those goodies but there weren't very certain terms that had to be followed i suppose.

I was just confused as to why it would run before.

Well thanks for you help.