- This topic has 2 replies, 2 voices, and was last updated 8 years, 11 months ago by
.
-
Topic
-
I have a 99 jeep grand cherokee with the 4.7L V8 engine. 141,000 miles. It idles really low and crappy rough idle at 450 rpm in drive and feels like its going to stall out but idles fine in neutral and park. It Has PO171 obd II code. I sprayed carburetor cleaner around hoses near the intake manifold and the throttle body but couldn’t find any vacuum leaks. New pcv valve, new throttle position sensor, new spark plugs and techron additive didn’t help at all. I am getting pretty Bad gas mileage. Drives fine though. Im pretty good with cars and this one has me stumped! Any advice appreciated this is driving me nuts. Thanks have a great day 🙂
-
Replies
-
Have you checked your fuel pressure?
O2 Sensor
O2 shorted to ground
O2 heater operation
TPS voltage greater then .92 w/throttle closed
TP sensor sweep
Map sensor operation
ETC sensor operation
Engine mechanical
fuel pressure high
or PCM
- You must be logged in to reply to this topic.