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Discussion Starter #1
Guys, I have a problem with my 97 P38 4.6 that has got me totally confused. A while ago I was repairing a leak on the EAS and had the engine running on idle to fill the air bottle. Suddenly, I noticed it start to run a little rough and put out some black smoke. As I had worked in the area, I checked the MAF and IAT connectors were in place...OK. I stopped it and then it wouldn't start. After a few attempts, I found I could hold the key in start position longer and it would burst into life, rev to about 3000 and then suddenlty die like the ignition was shut off. My first thought was the MAF sensor, but that showed resistance, as did the IAT, and neither should stop the engine from starting anyway. I bought a new Crankshaft Position sensor but still no change, and the old one showed the normal resistance of 1.3KOhm.
Fuel was being supplied so I checked the spark. On the right hand bank, all leads produced a very strong spark, but on the left hand the spark was very weak and intermittent. As the ignition is a Waste Spark System, I don't see how that is possible. All HT leads showed zero resistance on a multimeter. I removed the coil pack and checked and cleaned all the connections there. No problem. Wiring all good.
Here's the strange thing; while I was checking the spark, the engine seemed to be wanting to start so when I finished I tried it and it started easily though running very rough from the tailpipe sound, but it would not idle without my foot on the gas holding it around 1000 rpm. I left it then to work on the weekend but when I tried it then, it was back to no starting. I went through all of the steps I had already done and it again started with rough idle, running for a good ten minutes. Then it stopped and will not start now.

It's a long way to the nearest diagnostic facility so I would like to do everything possible before I hand the car over for the first time in its life. Has anyone ANY idea what could cause this wierd behaviour? Particularly the left bank/right bank spark strength? I refitted the original CKP but no change. What happened in the first place is odd, as it failed after about five minutes running on idle, with no load change, revving, or any other input from my side.
Thanks in advance for any ideas!
 

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check fuse 26 to see if its burned or bad.

it sounds like your coil pack is dying. the symptoms you exhibit could be characterized from a bad coil pack.ie: one or more of the 4 packs failing/failed

be aware if the coil pack is bad as i suspect you can do cat converter damage running it like this. check for misfire codes which will eventually show up
 

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Discussion Starter #3
Thanks, trichard. but with the Waste Spark System, each coil fires two cylinders - one on the left bank and one on the right bank. Inside the cylinder, the spark intensity is dependent on the cylinder condition, High compression & mixture produce more resistance and the spark is more intense than on the opposing cylinder which is on the exhaust stroke. But OUTSIDE the cylinder, if the same coil pack produces a high current on the right bank, it MUST produce the same on the left. The only variable is the HT lead, which I do not believe can fail all on one side of the engine at the same time....It sounds stupid, but maybe I should swap the right and left bank leads....? Incidentally, I tried to start her today and the engine fired up straight away, but would not stay running more than a few seconds, even with full throttle.......
I never had this problem with the "74 !

Thanks very much for your input! When I find out what the problem actually was, you'll be the first to know!
 

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Can you hook up a handheld OBDII scanner to get an indication of the Eng ECUs thoughts?
 

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Discussion Starter #5
As far as I am aware, the Gems Range Rover won't talk to an OBDII?
 

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Discussion Starter #7
Well, after a long wait for the parts, I just replaced the four coil packs and HT leads and....no change. still the same.
 

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The only other things i can think of are:

Cam position sensor
Crank position sensor
MAF
Throttle position sensor.

Its hard to say though, if you don't give us any codes.
 

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Discussion Starter #9
I know, it would be easier with the codes - if there are any. The MIL isn't lit when I do get it running. With the new coils, it all points to the Crank position sensor but that is also new. I'll check the ring on Saturday but the way it originally failed doesn't indicate that being the problem either. A wiring fault is the next suspect, I think.
 

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I bought a new cps for my old jeep. It still wouldn't run correctly. I changed 5 other sensors and still no difference. I finally took the cps back and got a new. The jeep ran perfect.

You might have a broken new cps. You should try a different one.

sent with the crappy autoguide app
 

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Discussion Starter #11
Thanks, but both sensors show resistance around the1.3k range so I think they are OK. i hooked it up to an OBDII but could only se the Transmission ECU with the engine rpm and throttle opening readings. The engine ECU was not there....does that mean what I fear it does? The throttle position read 99% but the sensor is OK, giving varying resistance when operated, and line continuity is good. Odd.
 

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Discussion Starter #12
I finally gave up and took the car to the well known RR specialist here (NOT the stealer) . Turns out it was most likely a poor connection at one of the connector blocks that caused the EMC to lose its program. They disconnected and reconnected everything, loaded the parameters again and the car is back to the way it was. No parts required. Would have been a good experience except they switched my like-new, 2007 Magnadon warranty supplied, rear view mirror with an old piece of crap that has the initial liquid failure symptoms. That's why, for me, giving my car to anyone for repair is the absolute last resort, at least in this country.
 

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Glad the engine is running smoothly again! Too bad you didn't have diagnostics available to have a look for yuorself.
As for the mirror, I'd ask it back! If you didn't authorize the work, they have no business touching it.

Filip
 

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Surely that's theft if they've taken the mirror without your permission?

If they were asked to look at the engine running problem, and nothing else, then they shouldn't just be taking bits off YOUR vehicle that they feel like... especially if you have also paid for the work they've been asked to do... I'd go back and kick up a stink..

If that's not going to work, apparently the later Disco II mirrors will fit (they also have an inbuilt compass) with just the swapping of a couple of wires in the connectors - might be cheaper than a new P38 mirror... however, I'd first be calling them up and asking them what right they have nicking stuff from your vehicle...

Marty
 

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Discussion Starter #15
I turned around and drove straight back when I saw that the mirror had been switched. The obvious problem is how to prove that the mirror was switched? It's just your word against theirs. Anyway, I sent them the e-mail interchange between Magnadon and myself, with the new mirror shipping info from 2007, and they have promised to give the the $350 that Atlantic British charge for a new one.
 

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I turned around and drove straight back when I saw that the mirror had been switched. The obvious problem is how to prove that the mirror was switched? It's just your word against theirs. Anyway, I sent them the e-mail interchange between Magnadon and myself, with the new mirror shipping info from 2007, and they have promised to give the the $350 that Atlantic British charge for a new one.
Proving the mirror has been switched should be easy, you paid for it, so it will be on your invoice. If you didn't agree for it to be changed, you don't need to pay for it.
 

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I turned around and drove straight back when I saw that the mirror had been switched. The obvious problem is how to prove that the mirror was switched? It's just your word against theirs. Anyway, I sent them the e-mail interchange between Magnadon and myself, with the new mirror shipping info from 2007, and they have promised to give the the $350 that Atlantic British charge for a new one.
I find it funny that they agree to buy you a new one... why didn't they just give your 'old' one back that they shouldn't have nicked in the first place....

Anyway - here's hoping they do stump up, and you can get it replaced... I guess you know where no to go back to again, even if they know their stuff... though they might think twice about randomly taking things from your vehicle next time!
 
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