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Discussion Starter #1
Hi all, I originally got my Vogue 4 weeks ago after been legally off the road since 2012. About 3 weeks ago I started to have an inconsistent idle and was told it was the AFM and so gave it a quick clean with brake cleaner, this didn’t fix the issue but I just put up with it. I then replaced the air filter. Fast forward to a couple days ago and I go to start the Vogue and it runs terrible for only a short while before dying, throttle had to be well down (video with throttle at least half to 3/4 down
). I was advised to remove plugs and have a look, they were all sooty so I cleaned them up ( ) and put them back in. Ran fine until this morning where I have the same issue. (Video of the vehicle running normally
) I was also told that it could be a lack of compression in a few cylinders that could be causing this? Can you hear this from the video? I hope this is enough info, if not will gladly provide any needed. Would really appreciate some advise/help please!! Cheers
 

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So is that video running "normally" or "abnormally"? It sounds rough as a bear's arse!!
 

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Definitely sounds like compression issues but also top end - engine rebuild I fear!
 

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Both I'd suspect. Sounds like a seriously baggy engine. Have you done a compression test? If I can tomorrow, I'll video mine as a comparison for you.
 

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Discussion Starter #7
Both I'd suspect. Sounds like a seriously baggy engine. Have you done a compression test? If I can tomorrow, I'll video mine as a comparison for you.
Ah not ideal ? nope I have ordered a compression tester should be here within 2 days. What values should I expect? That would be great if you can please
 

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Discussion Starter #8
Checked the plugs today and they are all sooty again. Also checked the pipes between air filter, AFM and the chamber and they are all good, there is a bit of filth in the chamber opening though, is that normal?
 

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1989 Range Rover Classic
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Ah not ideal ? nope I have ordered a compression tester should be here within 2 days. What values should I expect? That would be great if you can please
So I also heard what sounds like a cracked exhaust header or broken exhaust, but that's not the bigger problem. It definitely sounds like it's only running on 5 or 6 cylinders (could be injectors, compression, a stuck valve, plugs/wires, etc). In terms of compression, the '89 had 8.13:1 compression (the low compression motor), so brand new you'd see between 150-165PSI from the gauge. A tired motor will have around 115-130PSI, and below 95-100PSI, the pressure is too low to get ignition, which means the cylinder is basically dead. My 3.9 had around 120PSI per cylinder (average) for 5 years and it ran as sweet as a nut (nice and smooth, no smoke, etc), just with a lot less power, so there are other issues here besides ring wear. Do you have an automotive stethoscope and an infrared (laser) thermometer? Both are super cheap from amazon and very valuable. If it will stay running for a bit, you can use the infrared thermometer to see if some of the exhaust ports are colder than others (not firing). To see if it's ignition related, I also recommend an inline spark tester (also super cheap from amazon). You can plug it in inline to each spark plug (one at a time, shut down, switch wires, restart engine) to see if each one is actually firing or not (the tester has a clear housing with a filament that flashes brightly when the spark goes off). The loud clacking sound could be a collapsed lifter (kinda bad) or a stuck valve (worse), you can use the stethoscope on the valve covers to try and pinpoint which cylinder its coming from. Regardless, I'd worry about trying to get all 8 cylinders firing first. Hope this was helpful.
 

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Discussion Starter #10
So I also heard what sounds like a cracked exhaust header or broken exhaust, but that's not the bigger problem. It definitely sounds like it's only running on 5 or 6 cylinders (could be injectors, compression, a stuck valve, plugs/wires, etc). In terms of compression, the '89 had 8.13:1 compression (the low compression motor), so brand new you'd see between 150-165PSI from the gauge. A tired motor will have around 115-130PSI, and below 95-100PSI, the pressure is too low to get ignition, which means the cylinder is basically dead. My 3.9 had around 120PSI per cylinder (average) for 5 years and it ran as sweet as a nut (nice and smooth, no smoke, etc), just with a lot less power, so there are other issues here besides ring wear. Do you have an automotive stethoscope and an infrared (laser) thermometer? Both are super cheap from amazon and very valuable. If it will stay running for a bit, you can use the infrared thermometer to see if some of the exhaust ports are colder than others (not firing). To see if it's ignition related, I also recommend an inline spark tester (also super cheap from amazon). You can plug it in inline to each spark plug (one at a time, shut down, switch wires, restart engine) to see if each one is actually firing or not (the tester has a clear housing with a filament that flashes brightly when the spark goes off). The loud clacking sound could be a collapsed lifter (kinda bad) or a stuck valve (worse), you can use the stethoscope on the valve covers to try and pinpoint which cylinder its coming from. Regardless, I'd worry about trying to get all 8 cylinders firing first. Hope this was helpful.
Thanks for your reply Lance. Compression tester arrived today so have done compression tests on all 8 cylinders. Unfortunately I can’t get the motor up to temp because it won’t run at all so all these readings are cold with all the spark plugs out, and turned over the motor at least 4-5 times each cylinder test.

Cylinder - PSI
1 - 155
2 - 160
3 - 160
4 - 150
5 - 165
6 - 165
7 - 155
8 - 165
These are all good readings right?
 

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Discussion Starter #12
good readings.

now verify fuel supply
Great!! When I have ignition on and I push the AFM flap a bit I can hear the fuel pump, but when I turn the key to the ignition I cannot hear it prime or do an initial pump. I should be able to hear it prime correct?
 

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1989 Range Rover Classic
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Great!! When I have ignition on and I push the AFM flap a bit I can hear the fuel pump, but when I turn the key to the ignition I cannot hear it prime or do an initial pump. I should be able to hear it prime correct?
To be honest I've never heard mine prime, if you are under the truck listening when someone else turns the key I imagine you can, but it's not loud or obvious enough the hear when inside the truck. This definitely sounds like ignition to me though, not fuel. If you've got sooty plugs, that means bad combustion, I'd check to see which cylinders aren't firing, I'd bet it's more than one.


This is the spark tester I have, works great, and it will show you if the cylinder is firing or not, and if it's a good strong spark (should be a nice bright white, not a dull yellow/orange glow). Super cheap, easy, and definitive. I'd clean all the plugs and try each wire to see which cylinders you're actually running on.
 

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That's what mine sounds like.

Compression readings are good. Have you checked for fuel? Mine does audibly prime and I have a cut out switch to the pump. If it is starved, it simply won't run. That's not to say your fuel pressure isn't low but as it's running at least badly, it must be getting fuel. What is the plug condition? My advice would be to start with ignition parts: coil, plugs, leads, rotor arm and distributor cap. All relatively cheap so just replace with quality parts. Then, get it timed up properly. You also need to check that the firing order is correct. Once you have done all of that, let's hear it again. Mine runs well but if something is even slightly amiss, it just doesn't go. They are reliant on a strong spark.
 

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That's what mine sounds like.

Compression readings are good. Have you checked for fuel? Mine does audibly prime and I have a cut out switch to the pump. If it is starved, it simply won't run. That's not to say your fuel pressure isn't low but as it's running at least badly, it must be getting fuel. What is the plug condition? My advice would be to start with ignition parts: coil, plugs, leads, rotor arm and distributor cap. All relatively cheap so just replace with quality parts. Then, get it timed up properly. You also need to check that the firing order is correct. Once you have done all of that, let's hear it again. Mine runs well but if something is even slightly amiss, it just doesn't go. They are reliant on a strong spark.
Very nice... strong sounding motor..
 

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Haha thank you. I love it! It is a bugger for ignition parts though. It needs a dizzy cap, again! Only had one about 1000 miles ago!
 

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Discussion Starter #17
To be honest I've never heard mine prime, if you are under the truck listening when someone else turns the key I imagine you can, but it's not loud or obvious enough the hear when inside the truck. This definitely sounds like ignition to me though, not fuel. If you've got sooty plugs, that means bad combustion, I'd check to see which cylinders aren't firing, I'd bet it's more than one.


This is the spark tester I have, works great, and it will show you if the cylinder is firing or not, and if it's a good strong spark (should be a nice bright white, not a dull yellow/orange glow). Super cheap, easy, and definitive. I'd clean all the plugs and try each wire to see which cylinders you're actually running on.
Have just ordered one and should be here in a few days and will give it a try. Do I connect between distributor and lead or between lead and spark plug?
 

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That's textbook definition rough.

I'm going to second @LanceL's suggestion that it's something with the ignition system, especially because the compression reading are good.
That spark plug looks sooty and old, so I'm guessing the plugs, wires, distributor cap and ignition coil are due to be replaced anyway.
The RAVE manual has an ignition system test that's helped me a few times before. In case you don't have it, the link is below:

Ignition System Test:
284911
284912
284913
 

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Discussion Starter #19
That's what mine sounds like.

Compression readings are good. Have you checked for fuel? Mine does audibly prime and I have a cut out switch to the pump. If it is starved, it simply won't run. That's not to say your fuel pressure isn't low but as it's running at least badly, it must be getting fuel. What is the plug condition? My advice would be to start with ignition parts: coil, plugs, leads, rotor arm and distributor cap. All relatively cheap so just replace with quality parts. Then, get it timed up properly. You also need to check that the firing order is correct. Once you have done all of that, let's hear it again. Mine runs well but if something is even slightly amiss, it just doesn't go. They are reliant on a strong spark.
I did a few days ago undo the bolt in the end of the fuel line to the cold start since it’s been disconnected and some fuel did come out, but in terms of doing a fuel pressure test no. Plug condition is the same as other day unfortunately, smells of fuel and sooty. Have checked firing order by checking leads, all is good
 

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Discussion Starter #20
That's textbook definition rough.

I'm going to second @LanceL's suggestion that it's something with the ignition system, especially because the compression reading are good.
That spark plug looks sooty and old, so I'm guessing the plugs, wires, distributor cap and ignition coil are due to be replaced anyway.
The RAVE manual has an ignition system test that's helped me a few times before. In case you don't have it, the link is below:

Ignition System Test:
View attachment 284911 View attachment 284912 View attachment 284913
Great thank you very much. Will have a read through and get back
 
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