V8 hesitating

Tubes63 said:

Well, driving back from a seminar today, rolled down the window at the lights and heard two, maybe three cylinders firing. Had to keep the accelerator down to keep the engine going, all the while the car sounded like a 1960's four cylinder running for the first time in years. Bad smell coming from the engine, though in my panic I didn't catalogue the smell in my memory so unfortunately I couldn't explain it to you now. I just remember it smelled bad. People were staring at my car it sounded/smelled so bad!

Drove it to the nearest LR garage which is about three or four miles. Could hardly pull uphill in fourth gear, bumping back and forth all the way. Had to run it in third gear most of the way but sometimes even in second it was struggling to pull.

Dumped it at the garage and explained to the guy that if I can't leave it there I'd have to get a tow truck to take it away, which he understood.

So car's fooked. Hopefully it's nothing serious, like a dead coil/dizzy cap or something, but it certainly felt serious. Perfect way to cap off a crap week .

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such a shame youre far away from me cos im sure if we could get together on it we could find the root of the problem. ive spent so much time chasing daft faults with mine now im pretty good at diagnosing the relatively simple systems.

Mr Noisy said:

such a shame youre far away from me cos im sure if we could get together on it we could find the root of the problem. ive spent so much time chasing daft faults with mine now im pretty good at diagnosing the relatively simple systems.

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yeah haha. I appreciate the help you offered though. I'm just done trying to diagnose it myself now, I just want it to work

classic kev said:

If there was a significant EFI fault, the EFI warning light should be on (assuming it has one and the bulb is actually in place!). As fett said earlier the ignition parts need to be genuine not pattern. It might be worthwhile having the ECU read for fault codes but I would strongly suggest taking the pain and buying genuine dizzy cap and rotor arm - Lucas, nothing else will do.

The only other thought is your coil. An iffy coil could cause both injection and ignition faults. Try swapping with a known good coil and see what happens; do check the condition of the L.T. wiring though, look carefully at the spade connectors - they corrode and wires break.

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My point was, instead of riping out parts and throwing new parts/money at a motor, do the simple things first....i.e get the codes read
and yes, those faults light never fookin work!...what are ya thinkin:scratching_chin:...

I think we've established the ignition system is certainly somewhere most of us would go through. brittle wire breaking down insulation and worn out/or crap new service items is stuff we've all suffered from.....

let us know what happens on this one mate

joe1972 said:

My point was, instead of riping out parts and throwing new parts/money at a motor, do the simple things first....i.e get the codes read
and yes, those faults light never fookin work!...what are ya thinkin:scratching_chin:...

I think we've established the ignition system is certainly somewhere most of us would go through. brittle wire breaking down insulation and worn out/or crap new service items is stuff we've all suffered from.....

let us know what happens on this one mate

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Will do. The guy I've got looking at it now is already stumped. Said it felt like either bad spark (as you guys are suggesting) or something gone wrong in the fuel system, which I doubt.

He said tomorrow's his day for working on it, so we'll see what happens. I'll report back as soon as there's an answer!

Cheers.

Okay!

So, the garage told me that because it's one of the first injected models, there isn't really any way of plugging in diagnosis equipment, which is annoying to say the least.

What he did was replace the "ignition amplifier", and that solved the problem I was worried about (i.e. that it was running on like 2 cylinders when I dumped it in their car park). But it's still not running perfectly.

The damned engine still stalls occassionally (though less frequently) when I pull up to lights (this seems more obvious when it's been on the overrun, like when I've been engine braking coming to a stop as opposed to coasting), the fuel economy is still down on where it was and I can still feel a shaking through the steering wheel every few seconds at idle which I believe to be a misfire on 1 cylinder. It's driving me insane haha

I have to say, though, it seems now that the hesitation on accelerating seems to be mostly when the car is stone cold now. Before the amplifier was replaced it was all the time. Does that maybe point to any particular area?

Gotta drive down to London in a week or two so praying that she makes it!!!

Cheers guys, this one doesn't look like it's going to be fixed any time soon. I've got absolutely no confidence that any time I take the old girl out I'm going to make it back in one piece which is a real bugger

Now I've got to go rescue five fat blokes from Leeds and bring them back to Durham at 10 tonight, so we'll see how she does on that one. That sort of load could be the end!

its probably an idle issue, if its a 92 it should have hotwire which means there is a fault code reader you can plug in. hotwire is one of the easiest injection systems to work on although it probably requires the work more often than most. here it is:

Products

garages often sh away from these cars of tell you they are fine when they are not cos they are a bunch of cnuts and dont know how to fix em

youre best bet is some simple stuff your self, do you have a mulitmeter? if so we can tell you how to tune the AFM easily. cant remember if you have already cleaned out the stepper but that will be one too and also re-set the base idle. ask us how first though as I fooked up my base idele once by jumping in without reading and it took some sorting out.

if you do not have a gen cap and rotor in landrover boxes then you must do that first along with either genuine or magnecore leads which I think you have?

it can be sorted, not usually by the local garage though and they charge you too much for fookin it up. I learnt that the hard way too.

also that sense of panic the car will fail at any second is normal landy ownership, the key is learning enough to fix it quickly your self . Myself and classic kev I believe drive areound with quite a few small spares that can sort most hotwire probs at the roadside with no more than a screwdriver/socket. armed with them and that knowledge you can sort most stuff bar mechanical failure easliy and quickly. its a shame you wernt here before as I sold most of that kit on ebay not so long back.

Thanks for the advice, fett.

I can't afford to fork out for the hotwire reader at the moment, I need to pay for Le Mans by the end of the month and am trying to save as much as possible for that; as soon as I can though I'll try to pick one up. I'll try to get a multimeter on Monday (or tomorrow if Halfrauds is open sunday)

The cap and rotor arm are genuine I believe, and the leads are Lumenition. I haven't given the stepper motor a proper clean in carb cleaner but I've wiped a lot of the blackness off with a dry rag.

Is re-setting the base idle a big/difficult job? Obviously I'll try other things first but just wondering.

And yeah when I lived in Oz I drove a '99 TD5 defender 130, and got pretty good at botching fixes out bush (sink or swim in most cases). But I've never had to work on anything electrical, it was always stuff like replacing and securing hoses that would rub on something on the rough tracks, or suspension or mechanical things... On time I had to stuff a wheel full of spinifex grass just to limp back to town because the spare had blown as well haha. But I hate electrics so much haha.

no setting the ase idle isnt too hard , you just gotta do it right lol and you will need a little clamp to seal off the bypass hose.

you need to check that cap and rotor is rea deal not just lucas. I cant empasise enough how much differance it will make to your problems. I know cost it happened to me me and I tried all the brands lol

I cleaned the stepper motor up a bit more and then took the old girl out for a 60 mile joyride last night. This is what happens now:

If I coast to a stop from a relatively high speed (so the enigine's idling for about 5 seconds before the car stops) then when I first start coasting the rev counter will drop to 0 then pop back up to a normal idle speed (600-800rpm). From then on the idle will stay steady until I drive off again.

If I coast to a stop from a low speed (so the engine's idling for 1 or 2 seconds before the car stops) then when I first start coasting the rev counter will drop to 0 then start hunting up and down, getting steadily more extreme, and requiring me to put a tiny bit of thottle in to steady it and stop it from stalling.

So basically no matter how long I coast the idle will pop back to a good speed and sit there, but if I come to a stop idling the idle will hunt and play up.

P.S. I'm pretty sure it's a genuine cap and rotor arm haha

get some carb cleaner on it and give it a really good clean and in the hole too

Will do. Just went to Halfords and got myself a multimeter (finally). Time to go back and get the carb cleaner :doh:. So damn forgetful haha

Have you checked your vehicle speed sensor is working (correctly)?

I had idle/coasting problems when that failed on me. I opened it up, cleaned it and performed some soldering and packed it with grease. Has been reliable since...

Mr Noisy said:

Have you checked your vehicle speed sensor is working (correctly)?

I had idle/coasting problems when that failed on me. I opened it up, cleaned it and performed some soldering and packed it with grease. Has been reliable since...

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Nah I haven't. That's the little plug on the transfer gearbox/near the handbrake right? How would I know if it's working properly?

Is it just a question of unplugging then unscrewing it, cleaning it and greasing it?

fett said:

get some carb cleaner on it and give it a really good clean and in the hole too

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Done this now by the way, on the sensor and inside that little hole. Might it be worth cleaning out the entire plenum? Or would I just break something haha

no its a good idea, you will need rtv sealant to put the top back on

Tubes63 said:

I cleaned the stepper motor up a bit more and then took the old girl out for a 60 mile joyride last night. This is what happens now:

If I coast to a stop from a relatively high speed (so the enigine's idling for about 5 seconds before the car stops) then when I first start coasting the rev counter will drop to 0 then pop back up to a normal idle speed (600-800rpm). From then on the idle will stay steady until I drive off again.

If I coast to a stop from a low speed (so the engine's idling for 1 or 2 seconds before the car stops) then when I first start coasting the rev counter will drop to 0 then start hunting up and down, getting steadily more extreme, and requiring me to put a tiny bit of thottle in to steady it and stop it from stalling.

So basically no matter how long I coast the idle will pop back to a good speed and sit there, but if I come to a stop idling the idle will hunt and play up.

P.S. I'm pretty sure it's a genuine cap and rotor arm haha

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Check the vac advance is working. How does it feel if you gas it from standstill? Have you checked your ignition timing?

You mentioned base idle and the plenum? Yes take the plenum apart and thoroughly clean it, check/set the throttle disc, check/clean engine breathers, plenum and ram housing. Trust me you'll be surprised what a difference cleaning the plenum and ram housing can make if it is really gummed up.

classic kev said:

Check the vac advance is working. How does it feel if you gas it from standstill? Have you checked your ignition timing?

You mentioned base idle and the plenum? Yes take the plenum apart and thoroughly clean it, check/set the throttle disc, check/clean engine breathers, plenum and ram housing. Trust me you'll be surprised what a difference cleaning the plenum and ram housing can make if it is really gummed up.

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Standstill in neutral, the engine revs fine. If I open the bonet and operate the throttle from in there then when I give it a sudden bout of throttle you can hear a sort of spraying noise before the revs pick up but I seem to remember that this is normal.

However, if the engine is stone cold then the it will hesitate for a second before revving, which leads to quite an annoying ride for about ten minutes.

I haven't checked my ignition timing, but that's a pretty heavy duty job isn't it? I haven't got the skill nor the patience to do that haha (not to mention the tools). Suppose I could get a garage to do it.