Hello,

I have dreamed of owning an RX-7 for years now. One month ago today I made that dream become a reality when I purchased a 1991 Black GTU for $2400. A price that I think is a steal for a well cared for car.

The car is in really good shape and has just over 100k miles on the odometer. There are a few minor issues which I have begun to address that I need some advice on. Most notably is that the car idles funny. As in the car idles at 1200 to 1500 rpm constanly. The car pulses from 1200 to 1500. It also has a very rich smell coming from the exhaust, and the check engine light comes on whenever the car is at idle, but dissapears when the throttle is applied. I suspect the Oxygen sensor is to blame. Am I right? Is the timing perhaps off too?

I am not very experienced with auto mechanics, but am very skilled at other technical tasks. I prefer to do most of the work myself. If this is a problem with the sensor, how do I go about replacing it? Any comments would be most appreciated. Thanks.

 

I would think it is the TPS (Throttle position sensor)...


The Oxygen sensor is usually used during cruize only..


There is a procedure to test the TPS on here somewhere. just do a search....


-Zach

 

Well they sure are nice. Except when they don't work. Anyway, yea I am going with TPS as well. Mine just had some **** on it and when wiped clean it worked fine. I suspect it takes in a certain amount of air and it was plugged. You did get yours for a steal since mine has 140000, year = 89 and I payed 2000. Mine is in mint condition though so I really can't brag . The thing is that my stupid fog lights don't work. Anyone, are these prone to being mis-wired? MAKE SURE you change all the fluids. If not all make sure it is the OIL!!!! Have a happy time with the 7, Once you get it to your liking the thing will last forever, and it people's faces are priceless when you just walk up to them and say "I've got a Wankel."

 

It IS the TPS. My 91 TII had the exact same problem, along with intermittent hesitation during acceleration. Replaced the TPS and adjusted it and it worked FINE. I think you'll be happy when you find that the non-turbo flavor TPS is MUUUUUCH cheaper than the turbo TPS. You can order one from www.mazdatrix.com (usually cheaper than dealer...). I wouldn't try buying a used one, with that many miles, you will probably have the car for a while, so why not have a new part.

After you install it, you will have to adjust it. The method for 89-91s IS different than 86-88s, and whenever your ready, PM me and i'll send you detailed instructions for setting the TPS using a Digital Meter (you know the voltage measuring things...radioshack sells a great one for 18 dollars...)

Congrats on the purchase, sounds like a good buy once you get it running 100%.

Take it easy,

Joe

 

I also would agree that it is your TPS and take advantage of the offer to get adjusting instructions and put them into your fix-it file. They will come in handy again and again.
As to your car, I have a question. In 1991, there was only a coupe, convertible and TII offered, no GXL or GTU designations. Also the wheels were different than on your pictured car. Those are the 89-90 wheels pictured which makes sense along with the GTU designation. What does your title say is the year of the car? Just curious. This information courtesy of the 91 RX7 brochure...
RW

 

Curious thing about the GXL - GTU designation.. The car was listed for sale as a GXL, however when the DMV ran the vin number it came up as a GTU. Go figure. :P

Thank you all for the info! It has been a big help. Joe, I will PM soon about the HOW TO for the TPS adjustment. Thanks again.

 

The GTU was a TII without the turbo and the GXL was more of a rich mans luxurious edition. The GXL usually had Leather with powere everything and such. Usually the GTU didn't have power everything and it didn't come stock with leather. I believe that LSD only came on the TII and the GTUs. The GTUs is also different from the GTU. Um there probably is more but I forget

 

Yep, that's about it. GXL was always the luxury version. GTU in 88 was the hot rod without the turbo. That became the limited edition GTUs in 89 and I believe a few were built in 90, though Brian Long's new book does not reflect any GTUs built in 90 for this country, but some on this site say there were. Go figure. The plain jane GTU is like the SE, but built in 89-90. I have a GTU with appropriate labeling as a parts car. In 91, there were no stickers or models. It was just the coupe, turbo and convertible.
Ralf

 

The GTU was a TII without the turbo and the GXL was more of a rich mans luxurious edition. The GXL usually had Leather with powere everything and such. Usually the GTU didn't have power everything and it didn't come stock with leather. I believe that LSD only came on the TII and the GTUs. The GTUs is also different from the GTU. Um there probably is more but I forget