Very, very strange problem

**Catmatt** · 7th August 2011, 10:37 AM

Out driving the car yesterday when out of the blue, the engine 'stumbled' as if it was fuel starved. Lights on dash all lit up - tacho keeps bouncing up and down and the temp guage went up to maximum.

Yikes - so I pulled over and shut it down. Checked under the bonnet - no evidence of running hot, no leaks or anything obvious.

Waited a few minutes and re-started...all good. No lights, temp spot-on & drives OK apart from another engine 'miss' on the way home.

Got home safely and while idling in the driveway decided to check all systems. I turned the headlights on and the engine promptly stopped

As a matter of fact - everything shut down apart from 1 headlight

Switched to parkers only and everything energised as per normal (Could hear fuel pump priming and the normal dashlights lit up prior to starting engine).....hmm - wierd and very strange.

Turned all lights off and re-started engine. Starts completely normal until I try the headlights and again, the engine stops and everything shuts down ....?????

I'm leaning towards a poor earth from the way the tacho is bouncing back and forth and the erratic lights but have checked engine earth, battery (Quite new and has good charge), fuses, switches and am stumped.......

Before I book into an auto-electrican - does anyone have an opinion or has had this happen to a TD5 D2?

It really has me scratching my head as I can't fathom why the engine would shut down when an electrical load is initiated....unless it was a poor or bad earth

....and where would the poor earth be

02 TD5 Disco by the way with just over 100K and has run like a clock to date.
Thanks for any assistance

**scarry** · 7th August 2011, 10:48 AM

I would check ALL electrical wiring & terminals under the bonnet & also battery terminals.Oil in the injecter harness?

**wrinklearthur** · 7th August 2011, 11:03 AM

Hi

Pay particular attention to all the earthing between the battery, body and the chassis.
Look at the crimped lugs and the fastening make sure they are clean then tight, especially were the cable is under the crimp, there shouldn't be any movment at all, of the wires inside the lug.

Cheers Arthur

**bob10** · 7th August 2011, 03:40 PM

Check oil in harness, my D2 went thru similar symptoms with oil in the harness, sends the ECU bonkers.[although I did not have the lights problem] Bob

**Catmatt** · 7th August 2011, 04:25 PM

Thanks Bob10 but after checking the ECU and harness connectors (Dry as a bone) I think wrinklearthur's suggestion was on the money.

I've double checked all earth points, removed them and cleaned up any dirt/corrosion and re-fitted. For no reason at all I made up another earth strap and have fitted it from a bolt on the T-case and run it to the chassis near the cross member and.................

It seems to have worked!!

Idles fine with lights on and off. Drives OK with all elecs running including charging lights etc off the aux battery.

Looks like rain this evening so another trip tomorrow with lights and wipers on will be the final test before I can be assured that it is fixed.

This has to be one of the weirdest ones I come across in years and wasted a free Sunday

Thanks for your assistance

**robbotd5** · 7th August 2011, 06:44 PM

Glad to see its sorted mate. Electricery again!!!
Regards
Robbo

**bob10** · 8th August 2011, 10:49 AM

One for the memory banks, Bob

**Rangerider** · 8th August 2011, 11:06 AM

Sorry to hear you had a problem my friend. Glad to hear you have fixed it. Daniel had a similar thing awhile back with his old Hi Lux, It was the earth lead from the starter motor to the body. Have just ordered the EGR kit as you suggested, next hoses, then the ECU. Still trying to find a set of ARB rock sliders ? GOOD WORK MY FRIEND !!!

**Pinelli** · 10th August 2011, 07:16 PM

I dealt with a similar problem a couple of years ago (not on a Landrover). I had just replaced the engine, from a carby model to a fuel-injected model with an ecu. Car started fine and idled. Gentle driving fine, up to a certain revs, and the car started to bunny hop. I assumed at first it was a fuel issue, quite naturally, and buggered around with the fuel pump and a surge tank.
Realise eventually that I had a resistive connection to the positive supply on the ecu. As soon as the the revs increased, current to the injectors and spark plugs went up, voltage to the ecu dropped and the ecu stopped. Almost immediately, the current dropped, bringing the voltage back up, and the ecu kicked back in again! It happened quick enough that the engine hadn't totally wound down, and so never totally stopped, with me bunny-hopping down the road like an L plater

Tacho bouncing around would also be explained by this, as it is driven by the ecu, and perhaps the temperature control as well.

**Catmatt** · 13th August 2011, 12:24 PM

Great input thankyou! The problem has re-emerged after being OK for 20-30K's of city traffic driving and starts exactly as you describe.....

All OK until revs rise (Just starting to get full boost and torque) when the engine has a split second miss - all the lights on the dash light up and stay on until I stop - turn engine off and reset ECU.

The headlight on - engine stops issue has me beat though. Just don't/can't understand how the headlight circuit can shut the engine down????

Thread: Very, very strange problem

Thread Tools

Very, very strange problem

Dry joint

Seems to be fixed

Problem not gone

Bookmarks

Bookmarks

Posting Permissions