justinss

I recently bought an 87 TII, and I am having trouble diagnosing some problems (although I may not really know what to look for, since I've only owned NA's in the past). First off, the previous owner did a few things to the car that may have some effect on how it boosts. He put a homemade PVC pipe TID on the car. I don't think there are any problems with it though. He also took the exhaust off from behind the cat, so it is left with only the pre-cat and the main cat (if the main cat is the next piece of pipe after the pre-cat). He also made a homemade BOV with a check valve from home depot. It works well too though.

Anyway, here is what I am experiencing. When I am accelerating, at about 3500 rpm the car makes a sound that is hard to describe. It's kind of like the sound you make when you hit your tongue to the roof of your mouth really fast (pa ta ta ta ta ta) or maybe like a small engine or something. It keeps making this sound while the boost gauge reads about a notch over the 0. At about 5000-5500 rpm, I can feel the boost kick in and the noise pretty much quits, but the boost guage never reaches the 40 inHg (which is like 7.5 psi I think). I know the car should be loud since it doesnt have a full exhaust, but when this noise kicks in, it gets louder.

Also, my TID and my blow off valve have oil in them. The pipe from my intercooler to my turbo also has a little oil, but from what I have read, it is supposed to have a little. The car doesn't smoke, and there is no for-aft play in the shaft.

Another thing I have is, whenever I start to take off (slow take-off or quick), the back end sinks down a little. Thanks in advance for your help.

justinss

anyone?

Touge fc33

im kinda in the same boat..except ive never ownd a rx before and never worked with turbos either just all motor hondas

anyways i got my car running yesterday after 3 years of sitting and when i would drive it i heard a whine which i think was the turbo but then when i shifted i heard a "dododododooo" in between every shift...what is that noise?and my car lacks huge amounts of power..the whole time i was driving it the boost guage never moved..what should i look for?

sorry to ask a question in your thread but i figured we were kinda in the same boat so why make 2 threads kinda the same ..if you want me to make a thread of my own just ask and ill move it

Rob500

Justinss:

Boost is basically a mechanical issue. If you have exhaust flow, the turbine is spinning, and the wastegate and BOV work - you should have boost. Engine timing and plugged up exhaust obviously impact boost. The previous owner did a lot of home made mods. How is the wastegate controlled? I've seen cars with home made boost controllers that never release the pressure on the wastegate controller. Thus the wastegate always stays open and no boost. Is the BOV staying closed? Maybe the noise you hear is the BOV. You should be making boost before 5K rpm. Stock boost on an 87 is 5psi.

Rob

RylAssassin

Couldent it be a clogged cat, it seems like that would limit the boost and make wierd noised like hes describing (although ive never heard a rx7 without a catback)
Why is it running without a catback anyways?? I mean its really loud, must smell terrible, and looks kinda retarded. Id say get an exaust system for that car ASAP! That should fix some probs. I mean you really need one anyway dont you think?

Rob500

If he really has no cat back I'm supprised the car hasn't caught fire.


Rob