High Idle Issue After Flat Battery
 

Hi All,
Looking for help.


I have a 1998 Grand Cherokee Orvis all standard.


Problem I left the keys in overnight and flattened the battery The key was left in the accessories position.


I jump started the car from a friends car no issue just started first time.
But the idle went to 2500 rpm very high as it usually idles around 900 rpm
if I put it in Drive the rpm falls to 900, but as soon as I put it in Park up goes the revs 2500


When I jump started the car I cant remember if the AC was switched to on position, if it was could a stuck AC relay cause this?
Please your thoughts and advice.


Thanks in Advance


Markie (Big Tent) in the UK.

you need to use the car some hours to get the ECU to read the sensors and re-program itself.
BUT, you could have a bad TPS or/and IAC. Its seems that if the TPS or IAC goes bad over time the ECU adjust to that, but then when you reset the ECU (remove power) it cant adjust to the bad sensors, i think.

Hi,
Thanks PWB for your reply could you clarify.
Whats is the TPS and how do you clean it?
I have found a good write up on cleaing the IAC idle Air Controll Valve and will try that.

Thanks again.

Markie

First put your battery on a charger and leave it until it's fully charged. I'd unhook the cables while it's charging (in case your key is on) ;) Your alternator isn't designed to charge up a discharged battery.

You cant clean the TPS, repalce it. Dont buy the cheapest one.