Car jolts/jerks - Page 3 - MustangForums.com


5.0L (1979-1995) Mustang Technical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.

Reply
 
 
 
Thread Tools Search this Thread
Old 06-07-2012, 11:39 AM   #21
mattdel
6th Gear Member
 
mattdel's Avatar
 
Join Date: Nov 2006
Location: Spfld, MA
Posts: 9,240
Default

Quote:
Originally Posted by cepowers18 View Post
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.
mattdel is offline   Reply With Quote
Old 06-07-2012, 12:03 PM   #22
cepowers18
3rd Gear Member
Thread Starter
 
Join Date: May 2004
Location: Richmond, VA
Posts: 614
Default

Quote:
Originally Posted by mattdel View Post
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?
cepowers18 is offline   Reply With Quote
Old 06-07-2012, 03:49 PM   #23
mattdel
6th Gear Member
 
mattdel's Avatar
 
Join Date: Nov 2006
Location: Spfld, MA
Posts: 9,240
Default

31-33 at idle, 37-40 with the vacuum line off (simulates WOT).
mattdel is offline   Reply With Quote
Old 06-08-2012, 12:06 AM   #24
Foureyed
 
Foureyed's Avatar
 
Join Date: Apr 2012
Location: TX
Posts: 35
Default

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.
Foureyed is offline   Reply With Quote
Old 06-08-2012, 12:23 PM   #25
cepowers18
3rd Gear Member
Thread Starter
 
Join Date: May 2004
Location: Richmond, VA
Posts: 614
Default

Quote:
Originally Posted by mattdel View Post
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  
cepowers18 is offline   Reply With Quote
Old 06-12-2012, 11:10 PM   #26
cepowers18
3rd Gear Member
Thread Starter
 
Join Date: May 2004
Location: Richmond, VA
Posts: 614
Default

Anyone? Code 311?
cepowers18 is offline   Reply With Quote
Old 06-12-2012, 11:45 PM   #27
mattdel
6th Gear Member
 
mattdel's Avatar
 
Join Date: Nov 2006
Location: Spfld, MA
Posts: 9,240
Default

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 11:52 PM.
mattdel is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
New from Pittsburgh chain New Member Area 6 08-17-2015 09:52 AM
Groaning noise coming from rear when turning right 92 5.0stang 5.0L (1979-1995) Mustang 4 08-13-2015 07:46 AM
FORD FRENZY!!! Milan Dragway-September 12th Milan Dragway Members Rides and Car Show Section 0 08-12-2015 04:43 PM
Torque Bias explained... ccwebb GT S197 General Discussion 2 08-11-2015 07:47 PM
Need Help Diagnosing Have Codes (Confused) djbigskrilla 2005-2014 Mustangs 13 08-11-2015 01:59 PM


Tags
1500, 2010, 2011, 2k, 5th, 89, changing, filter, fuel, gt, jerking, jerks, mustang, rpm, wot

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -5. The time now is 06:45 PM.