Lars Magne

Hello.

I have a 1993 Mazda RX-7 FD3S.

My problem is when i try to accelerate and get up to 5-6 psi in the intake manifold the car dies for a moment and then it comes again to the pressure is up to 5 or 6 psi again and then it cut's again.

I have measured the fuel pressure and it is fine.
I have also measured the voltage out of the MAP sensor and compared to the workshop manual and it works fine.

I havent tried to change spark plugs yet, but i have ordered new from mazdatrix, but it is probably a week until i get them.

Have anyone else had this problem???

gracer7-rx7

iTrader: (16)

Where are you measuring 5-6 PSI from? You are welcome to post a pic of the location.

What modifications does the car have?
Is the car new to you? Did this suddenly start happening after doing something or has it always done it?

Lars Magne

It is measured from the intake manifold were the air bypass valve gets its vacuum.

The car is new to me yes, and the car had this fault when it came to norway from japan.

gracer7-rx7

iTrader: (16)

Is the car running the stock ECU? If so, try and read codes. There is info in the FAQ thread on reading and interpreting codes.
If its not the stock ECU, then perhaps the previous owner has some odd tuning setup.
The gauge could also be inaccurate...

What RPM do you feel or see this cut? How long does it last? What is the general boost pattern over the RPM range?

Lars Magne

It is a stock ecu yes.

It can cut on 2500rpm, it cut's when the turbo start boosting. It is no pull what so ever in the car befor it cut's. When i give it full throttle and the turbo starts boosting the car cut until the boost have dropped... It isnt any boost controller or anything like that on it, it is stock!

gracer7-rx7

iTrader: (16)

Have you checked for boost leaks?

Try reading the codes and see where that gets you.