Loss of power and only 12 mpg?

  #1  
Old 04-17-2008, 08:55 AM
Thread Starter
Join Date: Apr 2008
Posts: 3
Default Loss of power and only 12 mpg?

Hi out there
Would anyone know off the top of tier heads what would cause an 81 Caddy to have loss of power (no get and go) and fuel milage so bad it would be cheaper to drive a kenworth?
the check engine light comes on on occasion not always (I don't know how to get the codes) and the valve train does have some noise in it.
If you have any ideas it would greatly help thanks.
Rob N
 
  #2  
Old 04-17-2008, 09:15 AM
Stealth's Avatar
Super Moderator
Join Date: Feb 2007
Posts: 3,945
Default RE: Loss of power and only 12 mpg?

ORIGINAL: runtime

Hi out there
Would anyone know off the top of tier heads what would cause an 81 Caddy to have loss of power (no get and go) and fuel milage so bad it would be cheaper to drive a kenworth?
the check engine light comes on on occasion not always (I don't know how to get the codes) and the valve train does have some noise in it.
If you have any ideas it would greatly help thanks.
Rob N
No missing? just lack of power ? timing?

Pull the codes and we can make an assesment.



 
  #3  
Old 04-17-2008, 09:26 AM
Thread Starter
Join Date: Apr 2008
Posts: 3
Default RE: Loss of power and only 12 mpg?

I'm not sure how to pull the codes for this car, it was a birthday gift to me from my inlaws.
 
  #4  
Old 04-17-2008, 10:46 AM
Tech Certified Members
Join Date: Jul 2006
Posts: 424
Default RE: Loss of power and only 12 mpg?

Hey runtime; Turn ignition on, motor off, go to the CCC and push off and warmer at the same time and hold untill 88 comes up and then let go of buttons. The codes will come up in numerical sequence like 27 30 38 then it will repeat them and go back to 70. write the codes down and get back to us. Sounds like TPS and the ECM are not relaying info. to each other.
 
  #5  
Old 04-17-2008, 10:56 AM
Tech Certified Members
Join Date: Feb 2008
Posts: 463
Default RE: Loss of power and only 12 mpg?

This is an 81. I think you have to ground 2 pins in the ALDL connector and count the light blinks. This person needs either a factory service manual or at the least a Haynes manual to proceed.
 
  #6  
Old 04-17-2008, 10:56 AM
Thread Starter
Join Date: Apr 2008
Posts: 3
Default RE: Loss of power and only 12 mpg?

THANK YOU
Ok got the codes the numbers are 24, 30, 45, and 88 came up again at the end not sure if it was supposed to or not.
 
  #7  
Old 04-17-2008, 03:36 PM
Tech Certified Members
Join Date: Jul 2006
Posts: 424
Default RE: Loss of power and only 12 mpg?

O.K. here we go, code 24 is the speed sensor cuircuit, possible failure. Code 30 is the Idle Speed Control cuircuit. Code 45 is the O2 sensor is rich. 45 is most likely a bad O2 sensor and they are easy to change. If you want to do it yourself you will need an O2 sensor socket to do the job. The socket is about $12 and it has a side cut out of it to accomodate the sensor wires so they are not damaged. Before doing the job just check all the wires and make sure the connections are good and the wires are sound and not broken or cracked. There is a possiblility that with these kind of problems that the ECM may be at fault. That was the case on my 81 and a reman unit was around $170. For the code 30 there is a sequence of test to determine if the ISC is functioning properly so let me know if you intend to try the work yourself , have been over this many times on mine. Code 24 could be a number of things too, defective speed sensor, defective buffer amplifier, defective wires or terminals, ECM not processing siganl, a speedo not functioning. Many diagnostic steps on this one too. Good luck and keep us posted.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
gopher
Cadillac Deville
0
03-20-2015 04:08 AM
Floyd Rivers
General Tech
0
09-29-2012 09:54 AM
mistrbbkp
General Tech
2
07-18-2007 03:01 AM
mar322
Cadillac SRX
0
05-30-2007 05:11 PM


Thread Tools
Search this Thread
Quick Reply: Loss of power and only 12 mpg?


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.