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Looking at a 8

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Old 08-18-2014, 07:38 PM
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Looking at a 8

Hey guys, I am about to trade my bike for a VR 8. Here is the listing. http://tampa.craigslist.org/psc/cto/4592633349.html Nevermind the wheels, they will be gone very quickly. I was wondering if anyone could fill me in on the TDC sensor. I couldn't seem to find any info on it.
Old 08-19-2014, 01:22 PM
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Glad there is some help going on in this forum.
Old 08-19-2014, 03:06 PM
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a TDC sensor is the same as a crank position sensor. Be sure to get a compression check before buying.

Also double check the engine codes to verify that it is the CPS.
Old 08-19-2014, 03:12 PM
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The low coolant light also looks to be on from what I can see in the pictures.
Old 08-20-2014, 11:53 PM
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Thanks. I have an appointment to get a compression test done. Also, I went and looked at another 8 today. Everything seemed good, but it seemed to have a loss of power. I was in 2nd gear and pedal to the floor it seemed hesitant and got to about 7K RPM and wouldn't go any further. Do you think that this is a sign of bad compression?
Attached Thumbnails Looking at a 8-20140820_194143%5B1%5D.jpg  
Old 08-21-2014, 12:04 AM
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I would also like to add that when I first started the car, there were some bad fumes. Could this also be caused by bad converter?
Old 08-21-2014, 05:18 AM
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Originally Posted by MazdaEight
Thanks. I have an appointment to get a compression test done. Also, I went and looked at another 8 today. Everything seemed good, but it seemed to have a loss of power. I was in 2nd gear and pedal to the floor it seemed hesitant and got to about 7K RPM and wouldn't go any further. Do you think that this is a sign of bad compression?
In regards to this one, I would probably go with clogged cat but also possibly a bad engine. The car seems to have been fixed up and the question you want to ask yourself is, do you trust this guys mechanical skills if he did mod his car? In my opinion, by just looking at the car, no. :P
Old 08-21-2014, 06:11 PM
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Alright, so I went and had a compression test done on the first car I posted about and it wad at 5.5 prettyuch all around. So no go on that. Now, the dealership (small privately owned) with the second car, daid they did a compression test and it came back as 98.7 psi. Is this even valid, and if so, what is it supposed to be for good compression under psi? Thanks in advance!
Old 08-21-2014, 06:33 PM
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OK, so what I have found in research and from racing beat here Rotary Tech Tips: How to compression check a rotary engine
the standard is 110-150 psi and minimum 75 psi.

So would you say because this engine came in at 98.7 psi, that it's on it's way to low compression?
Old 08-22-2014, 04:52 PM
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No replies? Wow, this site has changed since I had my last 8.
Old 08-22-2014, 05:02 PM
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Originally Posted by MazdaEight
OK, so what I have found in research and from racing beat here Rotary Tech Tips: How to compression check a rotary engine
the standard is 110-150 psi and minimum 75 psi.

So would you say because this engine came in at 98.7 psi, that it's on it's way to low compression?
How many miles?

That looks like it's on it's way to failing but it's unpredictable. All rotaries are ticking time bombs. They can fail at 50k they can fail at 200k.

You can gain compression from having maintenance items done, such as plugs wires coils and decarb cleaning but not by much.
Old 08-22-2014, 06:40 PM
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Originally Posted by MazdaEight
No replies? Wow, this site has changed since I had my last 8.
Don't mistake silence for apathy.
I try to help people within my scope of knowledge, but refrain from answering questions I know little about, like non-rotary specific compression test numbers.
The number of knowledgeable 8 owners is dwindling all the time I'm sure, judging from the amount of new owners asking the same questions repeatedly to the number of partouts and longtime owners moving on to newer models.
Old 08-22-2014, 07:01 PM
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I would not get any of those 8's. As a previous 8 owner, you should know what to look for in an 8. You're best bet is to go with a S2 RX-8 rather than an S1. You'll spend slightly more money but they are usually lower mileage and in better condition with a warranty.

Like BigCajun said, there are too many new members asking the same old question. The question regarding compression numbers can easily be found on this club. Also, what is the 8 going to be to you? Is it a daily, track, weekend? Are you in need of it to be reliable when you first purchase? There are a lot of variables to consider that us members do now know about as well.

I come on rx8club every so often, i do still have my 8 though it's currently having low compression on the rear rotor but I also have a MS6 and FD. I'm on rx7club more often now looking for rare parts and such than i am on here.
Old 08-23-2014, 09:41 AM
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Originally Posted by MazdaEight
Glad there is some help going on in this forum.
Originally Posted by MazdaEight
No replies? Wow, this site has changed since I had my last 8.
Those posts make you sound self entitled

Not happy?
Go to another forum.



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