If my Jeep Liberty suddenly exploded and I was granted full purchase value thru my insurance, I would not be sad. Well, maybe the environmental impact from the fire would make me rethink such a phrase. Thanks for letting mt vent.

Anyway, this post is regarding a surge I hear and feel in the engine compartemnt when I am at a stop while in gear or parked in park. The idle will be running fine then there will be a 2 second surge then idle fine again. Is this normal in a diesel? Maybe this is normal in a vehicle in general? Any theraputic response or comment will be grateful. Thanks.

Peace.

1. Have you cleaned your map sensor?

2. Fuel filter clogged. How many miles ago was it replaced?

3. Air filter clogged.

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2006 Liberty Limited CRD, Deep Beryl Green, Yeti tune, Arp studs, new cams, rockers, lifters, TB. "Green Monster"
2005 Liberty Sport CRD, Deep Beryl Green, GDE Hot Tune, ARP studs. "Rocket"
1982 Fiat 124 Spider Convertible. "Fiona"

Might be the AC compressor clutch cycling. I know mine has always been noticeable at idle when it is being used.

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2006 Liberty CRD Limited

Provent @ 43,000 km
SEGR in progress
SAMCO Sport hoses @ 48500 km
Goodyear Wrangler Duratrac LT225/75R16

I had the same problem with surging at idle or just off idle. I tried all the suugestions, cleaned the MAF, MAP, bled the fuel filter and then changed it. The only thing that got rid of it was installing the GDE ECO tune, so draw your own conclusions, for me it was EGR related - and it has not returned. It would be nice to hear Keith's views on that.

Thomas04,

Glen is right in this situation, most likely due to a partially clogged EGR system. The surge you are feeling is due to the intake throttle choking the fresh air flow in order to meet the mass air flow setpoint so enough EGR is flowing to the intake. The throttle closes to a point that causes misfire, the computer notices the issue and shuts off the EGR for a few seconds and tries again...to no avail. When you notice the problem again, just pull off the mass air flow sensor connector, if the problem goes away you have verified it is EGR related.

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Providers of wholly developed aftermarket solutions for the KJ CRD.
(248) 977 - 9531

I had cleaned out the MAP a little while ago. Drained the fuel filter recently and will be looking to replace it in another 10000 k/m. EGR was replaced 3 months ago and the MAF was replaced couple of weeks ago. I will check airfilter

I will attempt the removal of MAF sensor today, as it will happen today, and see what happens. There is also a device on the passenger side of the engine compartment the is now squealing. I believe this is the fresh ait temperature intake little cone filter on the end thingy. It has 2 or 3 little metal hoses coming out of the unit. Sorry about the description. This only started squealing sound after the MAF was changed at the dealer. Maybe the two are interrelated?

So I sat in front of my vehicle with the p-brake on for 10 minutes and tried to pin point the surging sound. It is located either in the alternator or just under the alternator. Not to sure what is under the alternator but will have a look hopefully soon. Could this be caused by the alternator?

mine does something very similar at idle, even when its in park, i think its the ac compressor kicking on and off though when i leave the defroster on, if i plug my egr in i have the same problem but even worse, i think my egr is clogged or something is messed up with the system, so i just leave the MAFS unplugged and it runs fine other than the change in idle noise when the compressor comes on

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05 CRD Limited, SEGR Kit, EHM, Selectrack Alpine DVD, 6000k HID headlights, Aux Lift Pump, 2.5" straight pipe, Diablo Extreme Puck, Euro converter
02 SLT Cummins H.O. 6spd manual with southbend 3850dd, fass 150hd, ddp 150hp injectors, arp studs, adrenaline stacked w smarty, traction bars, 6 inch stacks, level kit, bhaf

So I unplugged the MAF while the jeep was making the surging sound. Nothing changed. I thought maybe my Provent filter might be the cause so I have had it out the last couple of days and it has made no difference. There is a clear clicking sound on the right side of the engine bay (driver side) under the alternator. The AC compressor is on the left hand side (passenger side) and is not causing this sound. Maybe all there is to do is take it back to the dealer for the third time to see if they can charge me for another repair that will not solve this problem. Oh how I can't wait...

The clicking down beneath the alternator on shutdown is probably the FCV (Flow Control Valve). It's like a little butterfly flapper that the engine uses on occasion to limit the air coming into the intake (like a gas engine does). The normal behavior is for it to shut quickly on engine stop, then open back up again about 15 seconds after the engine stops (small brief motorized hum from that same area). If you're hearing harsh clicking that sounds like plastic gears grinding, then that's just what it is. You can (reasonably) safely disconnect the plug from the valve as it's not required for proper operation of the engine. Just pop off the cool side intercooler hose just in front of it to make sure the butterfly flapper is failing "open" and not "closed". If you want to take it out and clean/service it, there are 4 allen bolts around the perimeter of the unit that can be reached after the battery, alternator brace, and intercooler hose are out of the way.

Dan

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2005 Silver CRD Limited
245/75R16 GoodYear Duratracs
Fumoto drain | ProVent CCV Filter
Stanadyne FM100 filter | Cummins fuel pump
GDE Eco | SEGR | BoulderBars | FrankenLift | Frankenskids

Unless your vehicle has a completely different layout to the export model, the AC compressor is directly under the alternator, the heat pump and power steering pump is on the other (passenger side)?? However the FCV could be your problem.

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05 CRD Renegade

I would listen to Dan and Keith. Look at the old FCV & EGR posts from what seems years ago now. Your pollution control crap is failing. Remove, clean, re-install then immobilize it with the SEGR or GDE tune and drive it for the next ten years.

My , and welcome to the board.
Scott

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2005 CRD Sport - "Blackie"
Tow Package
Trac Loc
GDE EcoTune w/ unl torque
Goodyear Wrangler SilentArmor Tires
over 192,000+ miles
100k mile service performed
5V Glow Plugs Installed and ECM updated

Does anyone know the location of the Flow Control Valve in the Chrysler/Jeep Repair Manual? Is it classified as and engine componet? I have read other sites that claim both the EGR and FCV should be changed out at the same time. Has anybody on this site heard the same thing?

in the 2005 FSM, it's the section: EXHAUST GAS RECIRCULATION 25 - 23

The "FCV" is referred to as the "EGR AIR CONTROL VALVE" since (in theory), it's supposed to slightly restrict incoming fresh air slightly while the EGR solenoid is open. We don't want that fresh cool, turbocharged air pushing out the sooty exhaust, do we?

Dan

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2005 Silver CRD Limited
245/75R16 GoodYear Duratracs
Fumoto drain | ProVent CCV Filter
Stanadyne FM100 filter | Cummins fuel pump
GDE Eco | SEGR | BoulderBars | FrankenLift | Frankenskids

Adding to this the AC cycles on/off when in heat, by level and defrost modes

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)