1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Need Help: Rough Idling, Hard Acceleration & Car Shaking Like Hell

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Old Mar 25, 2010 | 03:24 AM
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Need Help: Rough Idling, Hard Acceleration & Car Shaking Like Hell

Done :
  1. ghetto compression test
  2. ignition coil
  3. igniter
  4. vacuum/hose leak
  5. fuel pump

could it be :
  1. AVC & PCV problem?
  2. water leaks to housing?
  3. carb problem?

it's 1982 S2, 12A
will post the video later
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Old Mar 25, 2010 | 04:01 AM
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did you do the fuel filter too?
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Old Mar 25, 2010 | 07:51 AM
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fuel filter is a prime suspect. also inspect the plugs for wear and corrosion. check the resistance of each plug wire and ensure they aren't arching. if what we've both mentioned is checked properly, including compression, its time for a carb rebuild.
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Old Mar 25, 2010 | 11:22 AM
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Check dizzy cap and rotor condition, too.
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Old Mar 25, 2010 | 12:17 PM
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Possibly bad fuel as well, water etc. in tank.
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Old Mar 25, 2010 | 04:54 PM
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What was the result of the ghetto compression test? While the engine is idling, pull 1 plug wire off at a time and note any changes in idle. If you find 1 wire that doesn't change the idle, inspect all of that part of the ignition system from the plug back to the dizzy rotor.
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Old Mar 25, 2010 | 09:03 PM
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Originally Posted by DivinDriver
Check dizzy cap and rotor condition, too.
Both replaced with new one. Any chance the pickup coil got problem? when i crank there are sparks at both T & L plugs, but i'm not sure if it is adequate enough to burn the fuel.
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Old Mar 25, 2010 | 09:11 PM
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Originally Posted by 2kilo2
Both replaced with new one. Any chance the pickup coil got problem? when i crank there are sparks at both T & L plugs, but i'm not sure if it is adequate enough to burn the fuel.
actually i just had the same problem with my car.. 79 (not sure what kind) 13B.. it had REALLY bad gas in it.. check ur spark plugs if they are falled then replace them and get a can or 2 of this stuff called SeaFoam.. works greak.. add about 6 gal of gas... should burn pretty well.. if it still idls funny.. replace the fuel filter...(might be 2 on ur car there is on mine) thats my suggestion
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Old Mar 25, 2010 | 11:46 PM
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Originally Posted by trochoid
What was the result of the ghetto compression test? While the engine is idling, pull 1 plug wire off at a time and note any changes in idle. If you find 1 wire that doesn't change the idle, inspect all of that part of the ignition system from the plug back to the dizzy rotor.
I got strong pulses from both rotors. I remember last week i've done that but forgot to note which plugs changes the idle when unplugged.

Originally Posted by Zackqw
actually i just had the same problem with my car.. 79 (not sure what kind) 13B.. it had REALLY bad gas in it.. check ur spark plugs if they are falled then replace them and get a can or 2 of this stuff called SeaFoam.. works greak.. add about 6 gal of gas... should burn pretty well.. if it still idls funny.. replace the fuel filter...(might be 2 on ur car there is on mine) thats my suggestion
Spark plugs seems fine, but not sure it had correct timings. i believe Seafoam only sold in US & Canada, not in my country (asia region), the best i have is MMO, i don't know if it is a substitute for seafoam. have stock it a lot since i realized that the MOP malfunction (few mths after i bought it from ex-owner + some searches in the forum).

Originally Posted by installer67
Possibly bad fuel as well, water etc. in tank.
Might be. I remember in the early 80's we only have RON87 & RON91 for our cars here. not sure which fuel is better as i stick with RON87 fuel.

Last year the radiator fins corroded & gone bad, i send it to the radiator shop to recore with new 3 row type. My mistake is i don't replace the water pump that time (coz of tight budget). Everytime i run 140km/h+ the engine temp starting to rise from normal temp to 110-130 degree celsius. Well engine overheat is bad for rotaries, but hopefully this is not in my case.

Last edited by mar3; Mar 26, 2010 at 01:02 AM. Reason: Merged back-to-back posts...
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Old Mar 26, 2010 | 12:10 AM
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Check your fuel filter first and foremost. It's a cheap and easy fix if it's the problem and just good maintenance even if it isn't the problem. The stock filters can clog up quickly and your symptoms sound like a clogged filter.
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Old Mar 26, 2010 | 12:11 AM
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Sorry guys for my bad english. I'm not that good in english. Hopefully you all understand the words i type here.

Originally Posted by orion84gsl
Check your fuel filter first and foremost. It's a cheap and easy fix if it's the problem and just good maintenance even if it isn't the problem. The stock filters can clog up quickly and your symptoms sound like a clogged filter.
Will do it ASAP. FYI, every time i filled in the gas i always mixed it with MMO or 2 stroke oil in the tank. I hope those MMO/2T oil is the reason the fuel filter clog up. I got no other way to run premix except by filling it in the tank.

Last edited by mar3; Mar 26, 2010 at 01:02 AM. Reason: Merged back-to-back posts...
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Old Mar 26, 2010 | 06:02 AM
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Just replaced the fuel filter, still no improvement. it must be something else.
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Old Mar 26, 2010 | 10:39 AM
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today i got chance to drive the car, max speed 100km @around 2500rpm for about 70km destination, water temp rise to 110 degree celsius which is not normal, coolant reservoir drying up (i filled up the radiator & reservoir before i drive).

possibility :

worn out water pump & inadequate air sucks to the intake which leads to carburetor Air/Fuel mixture problem (time to rebuild)?
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Old Mar 26, 2010 | 10:19 PM
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bump anyone?
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Old Mar 28, 2010 | 11:18 PM
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http://www.facebook.com/video/video.php?v=1258211581534
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Old Mar 29, 2010 | 01:35 AM
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nevermind, the rear rotor lost compression today. thanks for the help & suggestions.
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