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I dont know why I didnt think of it earlier. Someone else did. But now that I think about it this does sound like a converter clog. Drill 2 small holes in the pipe before the cat, if that fixes it then that is your problem. My friends MX6 did the same thing and that is how we checked it. If it makes a loud noise that sounds like air rushing when you crank it after you drill the 2 holes then it is a bad cat. Its not hard to have 2 tiny holes welded up.
 

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ECU is possible but Cat is def where I would start.

Honestly the cat is what this sounds like. Under load and after a certain point it bogs which says that more then likely.

I have had ECU problems and trust me its much different. Your car will rev just fine slowly but fall completely on its face if you floor it and you will smell so much gas its not funny. (You could reset your ECU unplug the Neg terminal and hold the brake down for 15 Secs or so and your reset on OBDI (93-95)).

As for the VAF, I doubt it. You can try it but I doubt it.

As for timing... I guess its possible but it would have to be 1 tooth (Any further then that and having a smooth idle and reving to 4k in N says there is most likely not a timing jump... however I guess it could be possible or the CPS to be out... but the ECU would throw the code). Personally I would return that Disty and get your 300+ back put the HEI back on and run with that as HEI is def much easier to replace and deal with (not to mention cheaper and the external coil options it opens up).

Let us know how it goes.
 

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i saw that a lot at a gm dealership i was at the cat would plug up and then no power. but you only need to find why it did it. most of the time it was raw fuel.
 

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how about the ECTS guys ? will that cause the problem too ? i had this problem a couple months back (my engine wouldnt rev up past 4-5.5k) and it turned out to be a clogged cat. good luck dude
 

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Discussion Starter #26
Thanks for the replys. I'm going to disconnect the cat (in front of it) and see what happens. Its a rusty mess on the exhaust clamp so it's not going to be fun. It's a catco cat I bought from Summit maybe about 3-4 years ago, I haven't really thought about it being possibly clogged because it's not a old stock cat. I just had someone revving it and I was watching the end of the exhaust and it does some very quiet back there and not much pressure coming out. My 94 rx7 puts out a lot more exhaust.
 

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I want pics of this cat this will be worth it lol
 

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hey tom ,I dont think its your ecu...if you would like to barrow anything just send eric I have a parts car here and 3 engines, check tps and I ac if I can Ill stop out next weekend and help figure it out.btw I just came back from Va with 2 klzes
 

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Discussion Starter #29
I want pics of this cat this will be worth it lol
YES YOU ARE GOING TO WANT TO SEE THE PIC OF MY EXTREMELY CLOGGED CAT!!!!! I will get the pic when I get the cat off.

I unbolted the exhaust from the manifolds (that looked easier than the extremely rusted cat bolts), and it was reving nicely, and higher rpms, no bogging when I would rev quickly like going full throttle. So then I knew it had to be a clogged cat. Then I cut the exhaust pipe in front of the cat with my sawzaw, looked inside to see the clogged cat, there is a bunch of junk in there. I'm not sure yet what I am going to replace it with. I'm gonna go drive it now and see how it runs, I tied up the exhaust pipe.

I'm very happy to have found the big problem, this probably is also the reason for my lack of power over the past year or two. Thanks everyone who helped or tried to help! Tom
 

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just get a screw driver and poke away. it will still appear that you have a can with no plugging issues
 

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I second that
 

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Discussion Starter #35
I just gutted out the cat. It took a while but I did the job with it connected to the back half of the exhaust system. The filter piece or what ever it is called, on the engine side of the cat was not in the correct place, it was just sitting in the middle on the bottom of the cat. Then there was a whole bunch of crap clogging up the back filter in the cat, some of it black. I busted it all up and pulled it out the front of the cat using some long needle nose pliers, and a peice of metal wire I used to fish it all out. I used a breaker bar and long drill bit to bust up the back filter that was still attached properly to the cat. I assume the small particles will just blow out the muffler.

I just need to get the correct pipe adaptor to patch the pipe back together right in front of the cat, and get the car inspected before I can legally drive it. I assume it won't pass an emmisions test with a gutted cat, assuming the exhaust fumes are going to stink badly like they do on my RX7 with no cat. I seen a universal cat at Advance auto parts and it was only about $80. I might have to get me one of those if the guy doesn't pass the emmissions, or drive an hour to a friends garage who will pass it like he does for the stinky rx7.

I hope the car doesn't sound crappy like it did when I had a test pipe (mid pipe with no cat) on before I got the catco cat, it sounded so much better after the catco hi-flow cat (which might have lasted a year before it must have started clogging up and taking away power!). It ran like 18 or 19 seconds last time at the 1/4 mile because of the power loss, too bad I didn't check the cat back then when I knew there had to be something wrong robbing me of power but I didn't know what, I just assumed the motor was going bad and losing power, glad I don't need a new motor.
 

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Hope you got those pics before you broke it all out :p

good to hear things are looking better for you!
 

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cat

just FYI tom, the filters u speak of are actually honeycombs of elements that help to reduce the amount CO, HC's and NOx gases that come out of your tailpipe.. depending on wat type of cat u have, there are two or three different elements that do this and they are platinum, pallidium and rhodium. like my teacher used to say, u learn something new everyday.
 

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Discussion Starter #39
The car now has alot more power and goes much faster than it has in a long time. And it sounds great with the gutted cat and greddy catback, it's not too loud. I can now go 60 again in 2nd gear, it only went about 40-45 in 2nd gear last time it was drivable, that cat must have started getting bad a long time ago. It might be running better than ever for me now that it has no cat, and a new/reman complete disty. It's hard to remember how fast it used to be because it's been so long since it has ran great (and the RX7 I have been driving too much lately makes everything feel slow lol).

I almost sold the car, now that it is running right I don't want to sell it.


Anyone else with a catco cat experience any power loss?? It might be clogging up, mine did quickly!
 

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LOL I should have bought your car instead :p then we would have a pic! :p
 
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