Been having issues with my 99 Cherokee lately
I'm throwing p0443 and p1685. My gas mileage is a steady 16. Mpg when it used to be 18 about. I also have to cycle the key twice to start it. Runs fine minus the bad gas mileage. Also I can pull the key out while it's running

 

I might help but I don't carry my trouble code decoder charts around with me. And don't feel like googling a problem not involving my rig. What issues do those codes refer to.
The key thing is a bad lock cylinder.

 

Po443 is related to evap purge solenoid and p1685 relates to skim and invalid key

 

Also I noticed when I cleared the codes by pulling the battery it started right up

 

NEVER disconnect the battery to clear codes.. That just HIDES the issue, by resetting the computer into learn mode. Chances are the codes will come back sometime in the next 50 start/run cycles.

 

With code P1685 I take it you have the Sentry Key Immobilzer System.

Here's some diagnostic data pertaing to 1685: The fact that you're having ignition key issues it may be related to 1685. Fix the ignition key issue and I'm sure it will clear this code.

P-1685 INVALID SKIM KEY

Set Condition: The PCM does not receive a valid key message from the SKIM.

Possible Causes:

INCORRECT VIN IN PCM
INVALID SKIM KEY NOT PRESENT
NO COMMUNICATION WITH SKIM
NO VIN PROGRAMMED IN THE PCM
PCM
SKIM TROUBLE CODES SET

Concerning the P0443 code, here's some diagnostic data:



P0443-EVAP PURGE SOLENOID CIRCUIT

Possible Causes:

FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
EVAP PURGE SOLENOID CONTROL CIRCUIT OPEN
EVAP PURGE SOLENOID CONTROL CIRCUIT SHORTED TO GROUND
WIRING HARNESS INTERMITTENT
EVAP PURGE SOLENOID
POWERTRAIN CONTROL MODULE

The EVAP Purge Solenoid is that gizzy mounted on the firewall that clicks. If it no longer clicks after the coolant temp gets up to around 150*F the control fuse in the JB may be blown. If the fuse is okay the solenoid assembly may be defective.

The fuse is #10 in the JB.

 

You're referring to under the hood correct,?

 

The JB (Junction Block) is the fuse panel in the passenger footwell.

Check the fuse but it may be okay because there are orther circuits protected by this fuse and if it were blown other sytems would be inop as well.

 

Yeah isn't the fuse

 

See if the solenoid is clicking after the coolant temp gets above 150*F. If it is, something else is wrong

If it isn't clicking check the electrical connector for corrosion.

The solenoid connector has two pins. The White wire is power from the F10 fuse in the JB, the other pin is a Pink/Black tracer wire which is the ground driver from the PCM.

You can use a voltmeter to see if 12 volts is getting to the connector and a test lamp to see if the ground driver is working. The ground should be pulsing. If you connect the test lamp to the Pink/Black wire pin cavity and provide the test lamp with 12 volts, you should see the test lamp flicker. Use an LED test lamp.

If all is okay, replace the EVAP Purge Solenoid Assembly.

FYI, I had to replace mine several years ago because of the same code.

 

Do you have a link to the part?

 

The OEM part number is 4669475AB.

Rockauto has them.

http://www.rockauto.com/catalog/raframecatalog.php

Judging by the manufacturers shown you can probably get them at Advance or O'reilly auto parts as well.

 

Thanks!

 

I just want to thank you personally for all of the help that you provide to us Cherokee owners. I have been building Bronco's, Scouts, CJ's and TJ's since the early 80's. I'm now 62 years old with 6 herniated discs and fingers that look like capital " C's". I got my first Cherokee a few years ago because wheelin is still in my blood and I needed a smoother ride and love my XJ. The forum has been very helpful to me with ideas and repairs. You and some others are most helpful all of the time. It really gets to me when members have to be rude and treat you like a dummy or insult you for asking a question. I utilize the search but there are times when my results to not address the exact specifics of my problem and the search results are generic to my problem. I am very hesitant to " Ask a question" and being reprimanded or having my intelligence questioned, or being crucified publicly. Everything but the help I need at the time. There are a number of solid members like yourself who want to help and share information. Then there is another group whose only design seems to be to bash, be arrogant or disrespectful. I wish I could thank all of the members like yourself, however you always seem to come up with solid helpful information, so I guess to me, you are the most gracious with your time and consideration and to that, I say Thank you!!!
Jplug2007

 

I just want to thank you personally for all of the help that you provide to us Cherokee owners.You are the most gracious with your time and consideration and to that, I say Thank you!!! Please see my other post CCKen
Jplug2007