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Discussion Starter #1
I am having my new-to-me 4.6 Callaway delivered Saturday. I bought it knowing that it has a misfire.

I own a 95 RRC LWB and a 2004 Discovery II SE7. This is my first P38.

The previous owner replaced the plugs, plug wires and crank position sensor in an effort to fix the misfire. He is fed up and decided to sell for parts. I bought the whole truck complete. Truck has 120K miles on it. Ran perfect then one day started misfiring.

He performed a compression check and all cylinders are pushing 165-175psi.

The carbon fiber intake elbow on the Callaway models are known to crack and fail. This one is no exception and has been wrapped in electrical tape to try and cure the leak.

The owner states the misfire only appears when accelerating under load. Idle is nice and smooth.

Any ideas on what to look at next?

IMG_2926.jpg IMG_2927.jpg IMG_2928.jpg
 

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Banned
1995-2002 Range Rover P38A
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A misfire under load is usually a sign of a weak spark, so as it has new plugs and leads, a dying coil pack would be next on the list. But it is a Callaway so could be far more serious......
 

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Discussion Starter #3
Received the Callaway last night and drove it. It idles perfectly and drives fine with very light throttle. Once you tip into the throttle and induce a load on the engine it stumbles and falls on its face. The carbon intake elbow is destroyed and held together with tape. I think this is the first item to address. Non metered air pulled into the engine could cause an extremely lean condition leading to loss of power and stumbling.

Anyone know of a replacement component for this carbon fiber piece? Would a stock GEMS intake elbow work?
 

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Discussion Starter #5
Replacing Coil packs and MAF this weekend.

Ill post results on Monday.

Going to try and repair carbon intake as well.
 

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Discussion Starter #8
So after going through the entire ignition system replacing MAF, coil packs and spark plugs still the Rover wouldn't run right. I then spoke to a British vehicle tech in Carlsbad (Carlsbad British Motorcar, Tyrone) who asked me if the transmission was replaced recently, which mine had been. He told me to look at the crank position reluctor ring mounted on the flex plate. What I was looking for was a bent pick-up tab and sure enough there it was! A single tab that was less than a millimeter out of spec. I used a drift and a hammer to realign the tab and started the car and problem solved!!!

This is something that I never saw referenced when searching for a fix online. I hope other individuals that are having similar issues find this thread useful.

Thank you, All for your time and helpful responses.
 

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Discussion Starter #9
Would Scotty have spares?Or a modified plastic/rubber boot?I would sure like to know about a replacement also..
I spoke to Scotty about replacing my intake tube and he doesn't have spares but advised me to pick up a 3" diameter 45 degree bend tube to replace mine with. I couldn't find anything at my local parts stores so I'm going to have a piece of exhaust tubing bent to meet the specs I need, then paint it satin black and cover in a carbon fiber look vinyl wrap to maintain the authentic look.

I'll post pics and thoughts when completed.
 

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JACK'S GRANDAD
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Less than 1mm out of spec? Really? Thats funny.... Also wondering how you measured ALL the teeth on the reluctor wheel to come to that conclusion.....
If LR had to work within 1mm on external parts, their heads would explode.

Martin
 

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JACK'S GRANDAD
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And I'm guessing your wanted ad is now redundant?
I am deleting it as Im guessing it is no longer needed.

Martin
 

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Discussion Starter #13
Less than 1mm out of spec? Really? Thats funny.... Also wondering how you measured ALL the teeth on the reluctor wheel to come to that conclusion.....
If LR had to work within 1mm on external parts, their heads would explode.

Martin
Well, Martin, I removed the flex plate dust shield and measured the distance between both input tabs all the way around the flex plate. When I came to a pair of tabs that were 0.98mm farther apart than the average, which was determined by the recorded measurements of all the other tabs on the flex plate, I bent them to be within "spec" and this resolved my issue.

Please leave my WANTED ad as it is. I have an interest in keeping an eye out for additional trucks/parts to keep mine going.
 

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JACK'S GRANDAD
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Ad is gone, so you can make another one asking for a spares car etc if need be.
I still find it hard to believe. I have made my own reluctor wheel for the LSx engine swap, and can happily attest to it not being within 1mm......Works perfectly, and is a GEMS crank sensor.
I would guess that something got disturbed and bumped back into position, to make it work correctly.

Martin
 

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Discussion Starter #15
Ad is gone, so you can make another one asking for a spares car etc if need be.
I still find it hard to believe. I have made my own reluctor wheel for the LSx engine swap, and can happily attest to it not being within 1mm......Works perfectly, and is a GEMS crank sensor.
I would guess that something got disturbed and bumped back into position, to make it work correctly.

Martin
Well, regardles of what you believe the solution to be, the moral of the story is to have a look at the reluctor wheel if you are having a similar issue.

By the way, the tech who pointed me in the direction of the reluctor wheel and attested to finding other P38's with this issue, stressed that a tab being even 1mm out of alignment could cause the sympton I was experiencing. I tend to believe him and his 30+ years of experience working in the British car industry.
 

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Your sensor mounting plate can be out more than that and cause no issues. The reluctor teeth have to be pretty seriously damaged to cause any issues at all, let alone cause any issues being 1mm out of true. The reluctor ring is only a hall effect. It is looking for the missing section, not how close the teeth are to the sensor.
 

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JACK'S GRANDAD
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If LR had to be within 1mm of anything on the outside, they would spontaneously combust there and then.
And all those years of experience can, and indeed does a lot of the time, equate to zilch. There are shops around Southern Cal that I wouldn't take a bicycle to, even though they have been around for years and years.....Weird huh?
End of story, folks can draw their own conclusions from here.

Martin
 

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JACK'S GRANDAD
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I've imported cars from California and can confirm that part swapping idiots with no conscience there seem to be either lying, don't have a clue what they are talking about or both.
There, fixed it for you.....rofl

Martin
 

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1995-2002 Range Rover P38A
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Only problem is that when they swap the parts, they seem to always fit them incorrectly. If something can be taken off and put back on a right way or a wrong way, it is invariably fitted the wrong way......
 
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