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Discussion Starter #1
Okay got another one. I searched, but cant find much.

I finished with the rebuild 4.6 Callaway engine and put it in a 98 HSE I bought with a bad engine, which had been sitting for about a year. I broke in the cam (15-20 min of 2k RPM), and was going to drive around 50 miles of varied throttle positions, before I started going full throttle to fully break it in. Today, I drove it, and accelerated harder than normal (did not floor it though) and went above 3k RPMs, to almost 3500. It immediatley lost power and went down, and I limped it to a parking lot. It idles just fine, and when you rev it, it wont go above 1200 RPM. Its almost as if a rev limiter is set at 1200.

I had a new fuel filter, so just to be safe I replaced it. Nothing. I disconnected the battery, in hopes to reset the computer. Nothing. It has brand new plugs and wires, which are in good shape. The coils look good. I took out and cleaned the MAF, TPS, and stepper motor. Same thing.

I think it is either the fuel pump, or ECU. I need to borrow some stuff from my dad to check the fuel pressure.

Sorry that was so long, but does anyone have any ideas?
 

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You would think the fuel pump would be an all or nothing, or perhaps build up some volume at idle that would at least let it rev momentarily. It sounds as though the ecu isn't receiving input on throttle position. Nothing to do with that errant plug?
 

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Had the same problem but at 2000 rpm. Throttle position sensor (tps) broken.Replaced and all OK.
 

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Discussion Starter #4
nipper said:
Had the same problem but at 2000 rpm. Throttle position sensor (tps) broken.Replaced and all OK.

I'll try the one from the old motor and see if it fixes it. Thanks
 

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Discussion Starter #5
I switched the TPS sensor with the old engine, and nothing has changed.

I checked the fuel pressure, and its at 37. I think that is within specs. Anyone know what the pressure is supposed to be?

I am starting to suspect the ECU even more.
 

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I would swap the Crank Position Sensor (right below the evap plug you just hooked up). When I did my rebuild the brand new outta the box sensor ws faulty. Swapped with the old one and all was good.
 

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Discussion Starter #7
rrtoadhall said:
I would swap the Crank Position Sensor (right below the evap plug you just hooked up). When I did my rebuild the brand new outta the box sensor ws faulty. Swapped with the old one and all was good.
I did not think of that. Did yours have similar symptoms?
 

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nickm347 said:
rrtoadhall said:
I would swap the Crank Position Sensor (right below the evap plug you just hooked up). When I did my rebuild the brand new outta the box sensor ws faulty. Swapped with the old one and all was good.
I did not think of that. Did yours have similar symptoms?
Yup. Mine would stumble and crap out at about 1500-1800RPM. Drove me up the wall because I knew there was no way the new sensor would be the cause. :roll: SO after pounding my head against the wall for a long while I swapped them for kicks.
 

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Discussion Starter #10
rrtoadhall-

Thanks again for the suggestion, looks like it is the problem. The one that came out of the old motor was bent and gnarled (the prong) from part of the cam going through the back of the block. I bent it, put it it, and it did the same thing, just at a different RPM. It is more than likely the sensor, so I just ordered another one.

Thanks again for all the help, and Ill update this with a confirmation if it works or not, for future reference.
 

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Discussion Starter #11
Okay

I replaced the crankshaft positioning sensor, and it is doing the exact same thing. Any other ideas on what this may be?
 

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Discussion Starter #12
Here is a video of whats going on. Its pretty low quality, but it gets the idea across. Its like I'm bounching off a rev limiter or something.

http://www.youtube.com/watch?v=Y0Ow7XkCvBI


Things Ive done with no fix: New Crank Position Sensor, Swapped used MAF, TPS, cleaned IAC, just put new plugs/wires in. I suspect the ECU. I have a Callaway ECU, but I think its locked out, so I put the PROM/chips from the Callaway into the HSE ECU, and again, no change (wasnt sure if it would or not). Fuel pressure is good, new fuel filter. As far as I can tell, the Alt. is in good working order, New battery, good battery cables. The Coil pack looks good from just looking at it in place.

Any ideas? I really dont want to tow it to the Land Rover dealership an hour away, and there are no indys in my area.
 

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do you have a Faultmate or similar diagnostic equipment ?
if it's not any of the obvious things TPS-CPS-MAF-ECU i'd be suspecting something in the camshaft or timing gear positioning....could be one or two teeth out.
i don't know much about this stuff but spend a lot of time with a coupla mates that are top mechanics. they have seen similar syptoms after rebuilds...mostly other mechanics or DIY rebuilds. apparently it's really easy to stuff up.
maybe worth investigation, if all else has failed.
my experience with dealers.....DON'T.....all they want to do is unbolt something and put a new one on without necessarily knowing how to fix it.

..............tasi
 

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Discussion Starter #14
Thanks for the advice. Im getting a hold of another ECU. If it doesnt work out, I'll give the machine shop a call, since they put the short block together.

Anyone else have any ideas? I am not familiar with what a cam sensor will do if it goes out. Is this something that could happen?

Thanks again for all the help
 

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Discussion Starter #15
I got another ECU, but didnt realize it had to be reprogrammed to the vehicle. I doubt it is the ECU anyway. As I was going through it again, i noticed I tightened one of the bolts too much for the TPS and it was not set. The bolt broke inside the upper intake, so I removed it (Callaway intake) and replaced it with the regular 4.6 intake (so i could remove the brooken bolt later). I also swapped coil packs while I was in there.

Now the engine will not even idle properly. It used the idle fine, then when you gave it gas it would act like a rev limiter. Now it just bounces around 1500 RPM without touching anything.

I even swapped another TPS and MAF from a '96 4.6, same thing happens.

I am a little stumped on what to do. Could this be fuel related? As in bad fuel pressure regulator, or injector?
 

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Discussion Starter #16
Ok, still havent fixed this yet. I tried just about all the everything, even took it to the dealership and they werent sure. I decided just to pull the engine back out and check the plate where the crank sensor goes in. It was previously knocked out by the machine shop, and re-welded back in. I thought maybe the weld broke, but its good.

The reluctor teeth on the flywheel (I think thats what they are called, the ones that go around the Crank sensor) all looked good but 2. One was bent a little, and one was missing all together. I would say this is causing my problem. Im in the process of getting a used flywheel.

Can anyone think of anything else that may be causing my problem? Im sure this is it, but while the engine is out, things are easier to work on.

Thanks
 

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Its not easy to try and fathom out what your problem is but it seems to be pointing towards an electrical issue, possibly a bad fuse box or relay....even a bad earth could cause this.

Engine ECU has power transistors (mossfets) that can go bad, if yours are then it would be the first I've heard of.

Also a badly installed intake manifold can cause this problem but Im assuming you went according to the RAVE manual, new head bolts and all....?.

I would try another engine wiring harness and solder earth/power cables
 

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Discussion Starter #19
I forgot to mention, when I took it to the dealership, they put it on the t4 computer (I think), and they said it only showed a general misfire code at and above a certain RPM, and that the valve timing was off. I popped off the front cover and the machine shop installed the Crower cam correctly, and this was confirmed with a call to D&D after I talked to Mark.

Seeing as how the cam and crank sensors have something to do with the timing, and everything else is fine (swaped used cam sensors, and new crank sensor), I feel like it is the missing and bent tooth that is the main problem

I have not inspected the fuse box, but it looked fine when I pulled the fuel pump fuse. The ground cables look fine, no corrosion or rust etc. There isnt much on the car. I am going to take some contact/electrical cleaner and hit every connection on the harness.

I found a new flywheel for $38 shipped. Im going to give this a try before anything else.

Thanks again for the input
 

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Discussion Starter #20
Just to update this thread for anyone with a similar problem in the future, it was the reluctor teeth on the flywheel. Just one broken and 1 bent tooth with screw it up.
 
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