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having engine and trans problems

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Old May 20, 2010 | 02:11 PM
  #1  
venom90's Avatar
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From: yuma, az
AZ having engine and trans problems

about a month ago i bought an 86 rx7 gxl for $450 but the engine need to be replaced. so i found a deal for 2 engines for $300 and i replaced the engine and got it running. i then noticed that on first gear it barely had power. so i decided to replace the throttle body and dynamic chamber with an extra one i got with the car to see if the would be any difference. i noticed that i made it worse because it has a hard time staying on. so now i have to give it a little extra gas so it won't die when I'm at a stop but when driving its just fine. i also noticed that the clutch is a little hard to engage even though the clutch still has some meat on it and the slave cylinder was rebuilt. the clutch does engage but it has a hard time when putting it into first or any of the gears.

Should i put back the throttle body dynamic chamber it had before?
Is first suppose to barely have power, if not what can i do to improve it?
What could it be thats making the clutch have a hard time engage?

thanks in advance

heres some pics of it



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Old May 20, 2010 | 07:35 PM
  #2  
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Not sure why you decided to change the TB and dynamic chamber at all. That should get you nowhere. In fact, if you didn't replace the gasket to the UIM, you created a vacuum leak. Vacuum leaks will stall the car at idle, and can cause hesitations.

1st gear has the greatest torque multiplication, which means the greatest acceleration. You could just have a blown engine. Compression test it.

For the clutch, you should probably bleed the system some more to be sure it's not full of air. You can also adjust the rod on the back of the clutch pedal to ensure solid disengagement. The FSM or a Haynes manual will tell you the spec for clutch pedal freeplay.
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Old May 22, 2010 | 11:20 AM
  #3  
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thanks for the info, I'll check the gasket to the UIM

i don't think i blew the engine, well at least i don't think so cuz i have barely driven it. I'll compression test as soon as possible. What kind of numbers should i get when i test it?

ok thanks I'll see to that

Last edited by venom90; May 22, 2010 at 11:42 AM.
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Old May 22, 2010 | 03:02 PM
  #4  
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From: phoenix, az
AZ

90 psi and up is good (the better the higher) any below is bad, and probabaly wont run at all below like 50-40.
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Old May 23, 2010 | 12:17 AM
  #5  
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ok thanks
i read that you have to remove the schrader valve. Why is that?
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Old May 23, 2010 | 12:45 AM
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If you don't remove the schrader valve, or hold a release button, you'll only measure the chamber with the highest pressure. Since a rotor has 3 faces, you need to see what all 3 show. With pressure allowed to vent from the tester, you'll see "bumps" for each rotor face.
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