I own a 91 Mazda Rx-7 Tubo coupe I’ve had for 99.96K miles. I am told I need a throttle body ( Mazda part #'s B370-13-650B Throttle Body and N370-13-645 Insulator). My current throttle is jammed open to full throttle. Mazda no longer makes the part and it doesn't appear to be available on the Mazda Dealer parts network. Any suggestion? I'd really like to break 100K!



This is the second time this has happened to the car. The first time was at ~30K Mazda replaced the throttle body for zilch. Is this a common problem?

Junkyard, or thepartstrader.com or you can go to Mazdarecycling.com and get the Phone # and give them a call..

how can it be stuck? Try using some wd-40, PEN etc and try and free it up. Maybe the TB mod might get rid of whats causing u the problem, its up top.

If a nut on one of the rods gets loose then the parts on the rod can get crooked and jam, leaving the throttle open. Take the TB out and see if anything is loose.

Oldguy,

there are 3 sets of throttle plates in the throttle body:

1) the primary plates (2) [bottom]

2) the secondary plates 1 (2) [top ... same plane as primaries]

3) the secondary plates 2 (2) [top ... in front]



the secondary plates open with the primaries but only past a certain angle



the front secondary plates open with a delay (when cold, via the double throttle diaphragm and thermo valve) with the back secondary plates (the ones in same plane as primaries)



Which ones are stuck open ? the primaries ?



FYI, the TB mod gets rid of the front secondary plates.



hugues -