92 classic

[jwb1266]

Having idle issues. Got a code 48 so I replaced the stepper motor. It now idles great at 700 rpm, except after about five minutes it will jump from 400 rpm to 1300 for about 20 seconds. It then idles at 700 rpm throws a code 44 and never has any other dramas. This code refering to the 02 sensors. Is it possible for the o2 sensors to cause the idle to do this. I also had the rear muffler replaced at midas three weeks ago, could this be the culprit? The muffler says cherry bomb turbo on it. I live on the big island of Hawaii and no one will work on the car. There is one rover mechanic and he does not have the diagnostic computer for this car, and is not very interested in working on it. Any help would be much appreciated. Thank you

 

[joey]

Muffler has nothing to do with your issues.

Lets start with the basics, since I haven't followed all your posts.

Last tune up?
plugs
Wires
Distributor cap
fuel filter
Mileage on the RR
Last time you cleaned the throttle body
Air Filter

O2 sensors will normally cause issues like poor fuel economy, not a spike in idle.

 

[jwb1266]

First off, Thank you for always responding to my posts Joey. Being isolated out here is difficult, thank god for these forums. About the car, It has 117,000 miles. I just bought it 1 month ago and dont know the history. It looks as if the heads were worked on not to long ago (judging by there cleanliness compared to the rest of the of the engine compartment). I have not replaced plugs, wires, distributor cap or fuel filter yet. I have replaced fluid in front and rear diffs, transmission, engine. Also new air filter, stepper motor, and soon to be abs pump when it arrives. Yesterday I cleaned the Mass air flow sensor and the car seemed to enjoy that. It idles good and will still throw a code 44 after about 5 minutes of idling. The idle no longer bounces as much, just a little 650 to 800 for about 20 seconds then throws the code 44.
One more recent experience is the battery is dying overnight. Everything is off in the car. I'll jump it and after 20 minutes of driving it starts up fine for the rest of the day. One morning its dead, the next moring it starts no dramas, the next its dead. I did not replace the battery but the sticker says it was replaced 12/07. Just when I think I'm making progress, now this. Yikes! I do plan on replacing all the things you mentioned too. Oh and i have spraed throttle body ceaner through the throttle body and have run sea foam just in the gas, I have only been using 93 octane. Thanks again Joey, I appreciate all your help, and the help of anyone else who replies.

 

[joey]

Draining battery could be alot of things... easy test is remove the negative battery post and either use a light tester or a multimeter and remove fuses until the amp draw is gone.

 

[jwb1266]

Seems to be that the fuel pump fuse is the culprit to the battery drain, any idea on why this would be happening. The pump shuts off with the key off so how could that fuse be drawing on the battery. Thanks for the suggestions!

 

[joey]

stuck relay.

 

[jwb1266]

Joey, could bad 02 sensors cause the rough idle? They are on order and will be replaced along with many other new goodies. Thanks for your help

 

[joey]

Bad 02 sensors can in effect cause a rough idle, since if they go bad it will cause the engine to run rich, which can foul spark plugs.

 

[jwb1266]

When the sensors come and new plugs i will replace simultameously, and get back with you. They are going to take some time to get here however. Shipping charges are rediculous, the tune of 135 bucks so they will be shipped to florida, then here for 25 bucks total. Unbelievable. Thanks and I'll keep you informed

 

[jwb1266]

replaced the fuel and main relay, and no more rough idle. All the other goodies go on this weekend. Thanks for the help