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vs322



Member Since: 08 Apr 2020
Location: Athens
Posts: 584

Greece 2004 Range Rover HSE 4.4 V8 Java Black
2004 V8 4.4 Rough Idle

My plus size girl is being naughty lately and drives me nuts. Stopped at a traffic light yesterday, she began to shake slightly but noticeably. It resembled the vibration felt while stopped on a bridge with traffic passing by on the opposite direction. But I was stopped on solid ground. The RPM seemed a bit lower than usual for idle (500-700) but I didn't think much of it.

Going home I tried idling with the gear selector at P R and N with the same results; not always getting at low RPM but whenever it did, the selector position made no difference. Whenever RPM dropped, the cabin lights would also dim a bit.

This morning, while cruising on the motorway, I got a solid CEL. Didn't notice whether it blinked before turning solid or it just came on straight.

Did the engine adaptations reset and CEL reset by disconnecting battery for 10m and touching +/- wire terminals.

When I restarted I was in for a surprise...

The engine fired up ut stalled right away and stopped with batt and oil press lights blinking briefly.

I repeated starting three times in total with the same result.

The fourth time it fired up okay and stayed on, idling at 1000 then 750 rpm.

Took her for a ride and everything seems okay, although the idle speed seems on the higher side 750-950 rpm most of the time, with 650-750 being the lowest and while at that range, there is no noticeable vibration...

This time of year, almost everyone is on vacation and all garages are closed Banging Head worst time of year to have a breakdown or worse, getting sick...

I'm thinking whether this could be MAF sensor related and if a cleaning would be in order? Otherwise, could that be an ECU glitch?

I have replaced the pcv hoses and have sufficient crank case vacuum. Non return air valve vacuum lines have also been replaced. Spark plugs are a few months old and ignition coils are less than a year old. O2 sensors are also newish, year and a half old. Rocker cover gaskets replaced a year ago...

The IID is arriving next week so any educated guesses are most welcome πŸ™

Post #604290 20th Aug 2021 4:30pm
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Gsxr1250dave



Member Since: 20 Oct 2018
Location: London
Posts: 890

England 

What type of spark plugs did you fit ? Please don't say iridium.

Post #604400 21st Aug 2021 8:09pm
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tb10



Member Since: 17 Feb 2015
Location: Bromsgrove
Posts: 337

England 2005 Range Rover Vogue 4.4 V8 Tonga Green

Does it run any better with the MAF disconnected?

Post #604403 21st Aug 2021 8:26pm
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vs322



Member Since: 08 Apr 2020
Location: Athens
Posts: 584

Greece 2004 Range Rover HSE 4.4 V8 Java Black

Gsxr1250dave wrote:
What type of spark plugs did you fit ? Please don't say iridium.


NGK laser platinum. BKR6E

Post #604406 21st Aug 2021 8:31pm
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vs322



Member Since: 08 Apr 2020
Location: Athens
Posts: 584

Greece 2004 Range Rover HSE 4.4 V8 Java Black

tb10 wrote:
Does it run any better with the MAF disconnected?


Did not try that yet. I'm thinking of having the thing cleaned on Monday, if I can.

Today drove some 120 km going hunting and she behaved well on the motorway and the city...

On today's reset, due to my other issue (HDC+Air Susp Inactive) upon starting, there was a high rev moment (1800) which then dipped to 450 but rapidly stabilized without going into a stall this time.

Post #604407 21st Aug 2021 8:34pm
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vs322



Member Since: 08 Apr 2020
Location: Athens
Posts: 584

Greece 2004 Range Rover HSE 4.4 V8 Java Black

Update, please your input πŸ™

I had the CEL coming on again on the motorway. Stopped over at a garage and checked codes, found running lean. I was in a rush so stupid me I didn't ask whether it was both or a single bank but I assume both from what was explained.

On cold startup (or after sitting a while) I notice blue smoke from the exhaust for a second, which promptly clears.

On a closer inspection in the engine bay, there a noticeable hissing noise from the back of the engine. I Don't remember that before.

I checked on the back of the PCV ' s round cover, there's a tiny port at its 6'oclock. That produces the hissing noise. When I put my fingertip it's sucked right in and hissing stops.

As I don't remember that hissing being there before, is this a sign of the pcv membrane failing? I don’t think that's normal?

Is the car usable with a failed PCV or do I risk severely fouling my intake?

Thanks


**Edit**

After educating myself further, the PCV membrane indeed seems to have failed. New PCV valve ordered. Will let you know if the problem is sorted with this.
As I see, the replacement work is a royal PITA. I wish LR had adopted the replaceable membrane setup like BMW. Not that I'm not up to the job but as this isn't an emergency, I can wait until my mechanic returns from his vacation and I'll make sure he wishes he hadn't Laughing

Post #604590 23rd Aug 2021 4:02pm
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vs322



Member Since: 08 Apr 2020
Location: Athens
Posts: 584

Greece 2004 Range Rover HSE 4.4 V8 Java Black

Having gathered all needed parts, decided I couldn't just sit, staring at the fattie for the rest of my leave. Local stealers wouldn't touch this job with a barge pole, for love nor money, as all they're doing right now, is booking appointments for next month.
I therefore mustered all my strength and perseverance for what (expectedly) turned out to be an absolute pig of a job.
By far the most difficult part was undoing the lower right hand side torx screw. Had to use mole grip pliers with a T30 bit attached just to break it loose and then slip joint pliers to fully undo. Replaced this one with a 5mm Allen head screw.
Lots of stupid curveballs thrown my way. Some smaller others bigger.
Thankfully I had done my homework and noticed that the central tube's rubber grommet was missing from the old pcv valve as it was stuck into the breather tube opening, inside the manifold. So I removed it and saved me a broken breather pipe and some more torture.
I also changed the rubber gasket LKJ000060 which had turned reasonably hard and had settled fully in its groove.
No more rough idling, no more bluish smoke upon firing up the beast, no more hissing noises under the bonnet.
Took her out for a spin and all seems to be smooth and normal again. Hope things stay that way.




Post #604963 27th Aug 2021 1:59pm
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