'04 Jeep Grand Cherokee with the 4.7 V8.
Ran fine yesterday, and most of today. Went to start it when leaving a store and it now idles ~1700 rpms out of gear, and ~1300 in gear.
Replaced the battery (was only readying 11V); Replaced TPS, cleaned TB and IAC.
Still doing it.
Thoughts on what else could cause this? I don’t really want to go spend $75 for a new IAC just throwing parts at it.
I know it’s a long shot, But when I ahd this problem with my nissan I had to do an “Idle Air Re-Learn” procedure. Not sure if Jeep has the same thing or not. It was a pedal dance with some idle time to let the computer re-learn the volume of air coming into the motor at idle and adjusting the rpms as needed to factory settings. Just a thought, sorry if it doesn’t help.
I’d have to guess something to do with a vacume leak?
This.
My parents have an 04 grand Cherokee that this happened to. Look on the drivers side within a foot of the firewall, It is a very common problem.
Fuck.
I read a bunch of posts and it seems to be 50/50 on bad IAC versus vacuum leak. For some reason cleaning the IAC does not seem to ever rectify the problem on the 4.7 and replacing it is the only option…:shrug:
Maybe get the engine smoked?
Replaced the IAC this am… still doing it.
No DTC codes.
No vacuum leaks that I can find.
Any other thoughts? MAP? Anyone have a scanner that will work on this truck?
We could run it to my old place. John has a scanner.
how did u check for a vacuum leak? just looking at hose, there could be a dry rotted/crack in one anywhere. u really shoud get some smoke for it
WD40 and carb-cleaner trick… had the fire extinguisher sitting 4’ away. LOL.
Luke - My dad is bring out my laptop/scanner, I’m just not sure what OBDII network this truck has; mine can read anything but the CAN bus.
Well, to conclude this thread…
Found it tonight… turns out it was a vacuum leak that even spraying shit down didn’t find the first time… Spent an entire can of TB cleaner but I found it… Spent $230 on other parts ($110 of which for a battery which I needed anyway)…
I had a cracked elbow on the PCV to Intake Manifold. Must have blown it off the intake the other day. Only issue is that it’s buried and impossible to see; you can only feel it. It’s under the cowl behind/under the back of the intake manifold.
Taped it up tonight; gonna hit M&M and find a replacement as soon as I can.
Thanks for the advice guys.
glad it worked out for ya… i would of bet any money on a crack somewhere 