I don't know my way around 2nd gen RX-7's very well, but I'll take a stab
here anyway.
A plugged up cat was my first thought as well, but since you do not have
one, it obviously cannot be plugged up. My suggestion would be to check or
have checked the mass air flow meter (MAF). Here's why: On some mass air
systems (versus speed density systems), there is no manifold absolute
pressure sensor (MAP). Instead, the engine's fuel demand is calculated
based on input from the MAF sensor and throttle position sensor (TPS).
Well, you ask, if there is no pressure sensor, then how does the boost gauge
work? The ECU calculates the manifold pressure, probably based on measured
air flow and engine speed. Now, if the MAF is malfunctioning and indicating
more air flow than actual, this could cause a high boost reading (because
the ECU thinks a lot of air is being packed into the manifold). Also, the
ECU will be adding fuel for all this air it thinks the engine is getting.
This overly rich mixture could cause the rough running you describe, and
could be burning after it leaves the engine (overheating the turbo and
making it glow red).
A large pressure leak between the compressor and engine could cause a
similar situation. You may also want to check for a seized up turbo,
causing high back pressure, rough running, and lots of turbo heat. However,
I don't know how you'd get high boost readings with a seized turbo.
Steve Wynveen
Mercury Marine
R&D Engineer - Engine Development
ICQ: 5764003
1994 RX-7 R2, Vintage Red, #141 SS (Milw. Region)
1988 323 GTX
----- Original Message -----
From: Patty Lee <aggressive@lanyap.com>
To: Team.Net <autox@autox.team.net>
Sent: Wednesday, December 01, 1999 5:32 PM
Subject: Mazda help!!!
> We desperatly need some 88 Mazda RX7 / Turbo help. We are located in
> New Orleans and are looking for someone to hold our hands through a
> problem or someone to bring the car to.
>
> The problems (which I presume are all related) are:
>
> No power and sputtering under acceleration.
> High boost readings. (on the guage on the dash)
> Turbo glows red hot (yes it did catch fire) on short test drives.
>
> Pretty much Mazda illerate, but have excellent mechanical skills.
>
> Help!!!!!
> Mike and Shane Poupart
>
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