O2 Sensor Question?? - DodgeTalk : Dodge Car Forums, Dodge Truck Forums and Ram Forums
Closed Thread
Thread Tools
post #1 of 2 Old 07-20-2009, 06:18 AM Thread Starter
Registered User
Join Date: Jul 2009
Posts: 38
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
O2 Sensor Question??

Recently picked up a 1991 D150 2wd which was originally a 3.9 V6 truck, but now sports a 1990 TBI 5.9 V8. When cold, runs great, however, when warmed up after just a few miles, runs like a bag of marbles! Hesitating and leaning out badly. I noticed the TB temp sensor is disconnected, as well as the O2 sensor, since a bung was not welded into the collector downstream of the header to accomodate it. I know this sounds obvious, but would not having the O2 sensor plugged in cause it to run this poorly?? I would say so, but just want to hear some feedback from you guys. Apparently, the previous owner thought it was fine to not have it connected! Thanks very much!!
Scooby67 is offline  
Quick Reply
Sponsored Links
post #2 of 2 Old 07-20-2009, 10:37 AM
Join Date: Oct 2006
Location: Terre Haute
Posts: 5,443
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It WILL run dis-connected but with both the Throttle Body Temp Sensor and O2 sensors dis-connected,,but then the poor 'Computer' has only the Map sensor& TPS and ECT to aquire it's 'look up' fuel and ignition info from. The problem with this is the computer never gets to 'closed' loop and keeps it in open loop. This will cause momentary enrichment then lean then rich....but it's not programmed to do this in a fast rate of adjustment as the O2 can give it the info much quicker as far as how lean/rich the burn is and how much spark lead should be used.. I would get those connected as soon as possible.
threetwos is offline  
Closed Thread

Quick Reply

Register Now

In order to be able to use most of our features, you must first register.
Please enter your desired User Name, your Email Address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
The registration process requires you to activate your membership by following a link in an E-Mail that will be sent to you immediately upon completing this form. You must enter a valid email address or you will not receive this activation code and you will NOT be registered. Your E-Mail address is NOT publicly available to anyone as policy.

AOL E-MAIL USERS: Please click HERE for important info pertaining to your e-mail address.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Map Sensor, Air intake Sensor, & Engine coolant sensor Txaircraftmech 3G Dodge Ram Performance Talk 6 05-04-2007 09:51 AM
O2 Sensor Question 98RamSport 2G Dodge RAM - General Talk 6 03-15-2007 08:16 AM
O2 sensor question Hieneken49 2G Dodge Ram Performance Talk 4 08-17-2005 08:01 PM
O2 Sensor Question MrMonkey39 2G Dodge RAM - General Talk 11 10-07-2004 10:03 AM
Sensor Question black87 2G Dodge Dakota General Talk 2 07-10-2002 11:35 AM

Posting Rules  
You may post new threads
You may 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

For the best viewing experience please update your browser to Google Chrome