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Car jolts/jerks

Old 06-07-2012, 10:39 AM
  #21  
mattdel
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Originally Posted by cepowers18
Also, my fuel pressure is around 42 or 43 at idle. Not sure if that is too high for my engine and mods.
Way too high. Fuel pressure values shouldnt change much with mods. Only reason to have 42psi at idle is to be producing like serious HP, funny car serious. Too high of fuel pressure can actually snuff out the spark.
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Old 06-07-2012, 11:03 AM
  #22  
cepowers18
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Originally Posted by mattdel
Way too high. Fuel pressure values shouldnt change much with mods. Only reason to have 42psi at idle is to be producing like serious HP, funny car serious. Too high of fuel pressure can actually snuff out the spark.
What is an acceptable range? I've read that around 30 psi is about right at idle... does that sound correct?
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Old 06-07-2012, 02:49 PM
  #23  
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31-33 at idle, 37-40 with the vacuum line off (simulates WOT).
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Old 06-07-2012, 11:06 PM
  #24  
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My GT had an occasional case of hiccups awhile back, not sure if its the same problem you're having, but I changed the ignition coil and ignition switch and it solve the problem.
Hope this helps.
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Old 06-08-2012, 11:23 AM
  #25  
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Originally Posted by mattdel
31-33 at idle, 37-40 with the vacuum line off (simulates WOT).
Alright, so I have slightly more positive results to post. I adjusted the fuel pressure down to 32-33 at idle and 37-38 with the vacuum line off. This helped a lot in terms of the car not shutting off and maintaining idle when at normal operating temp. Also, the jolting and jerking for the most part has smoothed out, but there is a little bit of a hiccup still left.

After I took it out for a test run, I came back and ran the KOEO and KOER tests again. KOEO I got a 111, so I'm still good there. KOER I got a 311 code and then the car shut off during the test. The book says 311 is Thermactor air system/fault during engine run self-test. From what I've researched so far online and on forums, this has to do with the smog pump and is on the right side.

Can anyone help explain this code and what may be wrong with the smog system? I don't know much about them or what to check.

Also, fl1a, my oil pressure needle stays steady when at operating temp. I got under the car this morning to find that I have an oil leak. Pics attached.
Attached Thumbnails Car jolts/jerks-oil-leak-1.jpg   Car jolts/jerks-oil-leak-2.jpg  
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Old 06-12-2012, 10:10 PM
  #26  
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Anyone? Code 311?
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Old 06-12-2012, 10:45 PM
  #27  
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311 is: air injection system inop during test.

Possible causes:
vacuum hoses damaged
air bypass valve inop
air pump inop
tab/tad solenoids bad/damaged (50-100 ohms resistance between the terminals is acceptable, otherwise junk)

inop means inoperative, btw.

Last edited by mattdel; 06-12-2012 at 10:52 PM.
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