Please help! I have just got a 1988 Turbo II and was out playing with it the other night. It pulled really smooth and idled great, until just before I got home. It would run up to about 2k RPMs and then drop quickly to about 1k, then do the same thing over and over again, very consistently. Will a vacuum leak cause this?

 

first thing get some carb cleaner and spray and see if you have a vacuum leak from a popped off hose. if not you can your TPS. those are the two most common problems

 

Okay, thanks! I'll try that this weekend.

 

Is this the first time driving it this long? If it is, it is probably your TPS. When Mine went bad, it always acted up well after the car warmed up. Then Again, It could just be a vacuum leak!!



Good Luck!



Brandon

 

Well, I still haven't fixed it, but I know a little more. I can't find a vacuum leak, but some of the tubing is suspect. I plan to replace all of it as soon as I can order some silicone tubing. The up and down thing starts only after the car is fully warmed up, and it bounces between 1400 and 1600 on the tach, about once every two seconds or so.

 

It really looks to me like a TPS adjustment and even more, the whole idle setup process. When I bought my RX7 about 12 years ago, I went to a Mazda dealer and repair shop in order to set idle speed and got home with about the same problem as you. So I bought the Haynes manual and decided to do it myself. That was the solution for me. But it costs nothing to check it.