Disco 2 no start head banger
#11
Is your Alarm light blinking, solid, or off?
Disconnect your ECU. Clean the contacts. Reconnect.
Try motor.
If no start, reset under-hood fuel rollover cutoff and try starter fluid.
Repeat the above 1 at a time for MAF, then under-steering fuse box, next BCU, then under-hood fuse box, and finally grounds if problem persists.
Disconnect your ECU. Clean the contacts. Reconnect.
Try motor.
If no start, reset under-hood fuel rollover cutoff and try starter fluid.
Repeat the above 1 at a time for MAF, then under-steering fuse box, next BCU, then under-hood fuse box, and finally grounds if problem persists.
#14
Thanks xrad and nodboubt for ideas. Went at it again yesterday afternoon, spraying fluid in to manifold directly, still not even a hiccup. reset and swapped intertia switch - nothing. Tested coil resistance a bit high at 25K. Made sure all plugs are at least firing with sparky. Today will pull a plug or two and have a look. There have never been any electrical oddities or issues with the truck, the key fob and alarm/ red dash lights are all working normally, and I would think if it was fuse box ground or the like there would be other bizarre things.
I'll try the ecu et al unplug routine from nodoubt and double check the grounds, and make sure the cam position sensor didn't somehow come loose. To bad those ecu plugs are so hard to remove! A buddy with a better code checker may come by and see if there are any pending codes that don't show up on my harbour freight cheapo code checker.
Stay tuned!
I'll try the ecu et al unplug routine from nodoubt and double check the grounds, and make sure the cam position sensor didn't somehow come loose. To bad those ecu plugs are so hard to remove! A buddy with a better code checker may come by and see if there are any pending codes that don't show up on my harbour freight cheapo code checker.
Stay tuned!
#15
Try swapping coils? I still think its weird that with starting fluid and spark, you get nothing. Sounds like a spark issue. Fuel pump should kick on as soon as engine rpms signals appropriate, but lines should be holding pressure....So fuel pressure gauge on rail?
Last edited by XRAD; 04-01-2020 at 03:03 PM.
#16
Well the mystery continues, it was raining and snowing outside so it was yesterday evening before I could get to it. Checked plugs they looked good and are recently new. Unplugged one at a time with battery removed ECU, BCU and MAF, with no luck. Inertia switch swapped with known good. All other electrical seems fine and no codes. In spite of checking spark to each plug still won't fire at all with ether. Down to fuse box grounds maybe or weak coils, perhaps camshaft sensor but just guessing. Rover mechanic is 30 miles away, hoping he will go mobile or I will have to drag it to him. Man, never seen anything like it. NW Rover has no rust, this is a high dry climate.
#18
You need to verify fuel pressure, pump running does not necessarily mean you have correct pressure or pressure at all. You've verified spark, which is good.
If you have spark and verify fuel pressure with gauge and have good crank sensor...then l'd be looking at timing chain. But, normally you don't get the symptoms you've described (hesitation, poor acelleration, then hard start, then no start) with a timing chain issue. But, once you verified fuel, spark, crank sensor...l guess you have to go there...which means pulling a valve cover to see if valvetrain is moving.
Me, l would be verifying fuel pressure, first and foremost. Diagnostics are all about verifying components and systems. When you don't verify systems and start jumping around looking for all kinds of different recommended issues...you are just doing yourself an injustice...since you may have had your mind and hands on the issue long ago...but didn't actually verify if it was working 100% correctly.
Brian.
If you have spark and verify fuel pressure with gauge and have good crank sensor...then l'd be looking at timing chain. But, normally you don't get the symptoms you've described (hesitation, poor acelleration, then hard start, then no start) with a timing chain issue. But, once you verified fuel, spark, crank sensor...l guess you have to go there...which means pulling a valve cover to see if valvetrain is moving.
Me, l would be verifying fuel pressure, first and foremost. Diagnostics are all about verifying components and systems. When you don't verify systems and start jumping around looking for all kinds of different recommended issues...you are just doing yourself an injustice...since you may have had your mind and hands on the issue long ago...but didn't actually verify if it was working 100% correctly.
Brian.
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ahab (04-03-2020)
#19
Because the timing chain would bind in the gears and cover, possibly breaking the cover, and/or the oil pan.
If the chain broke and somehow managed to drop into the pan Without causing external damage, then the engine would turn over a little faster, and more freely, as it would no longer be driving the cam/valve train.
However, it should be extremely unlikely for 4.0/4.6 timing chain to break, as they are pretty heavy duty.
The 4.0 block I'm rebuilding my 4.6 in was a short block when I got it, and the bores are in really good shape.
The cam had a little wear, the cam and crank gears look new, and the timing chain looked new. But, once I grabbed the timing chain, I was suprised at the extreme amount of slack that it had from basic wear and tear.
It looks identical to the new one I have, but before I removed it, it's full left to right movement on both sides was a couple inches.
It had so much slack that I can't belive that there wasn't any wear against the inside of the cover.
The new chain is tight, and a dramatic improvement.
Point being, the odds of a timing chain breaking will be slim, and if it did, it should be easy to tell, even without disassembling anything.
Last edited by Sixpack577; 04-03-2020 at 08:11 AM.
#20
Thanks guys, I would think spraying ether in the intake manifold (directly into the throttle body) would have induced at least a cough, and I can smell fuel and starting fluid coming out the tailpipe. I should verify the fuel pressure I agree. Fortunately a Rover specialist in the area has said he would come take a look, I have to get my head out of it for a while! I will keep you all posted. My money is on the coils or the camshaft sensor, but both (especially the coils) are such a #4%@* to change I don't want to do it unless I'm reasonably sure. Motor sounds normal cranking over, normal enough that you just expect it to start.