landrover base off road nightmare !! running issues 3.9efi

Hi , I am new to this site so please be gentle .....

I have acquired a landrover based off roader , from what I can gather is a disco 3.9v8 efi hotwire engine .

symptoms :
starts on the flick of the key
idles nicely but maybe a little lumpy for a v8
revs through its range in park but then sounds lumpy

Drive it and feels like 4 plugs just fell out of it down the road , no power , no acceleration , popping etc etc

Bits I have looked into :

plugs new
leads new
rotor arm new
dizzy cap new
oil flush and change with oil filter
compression test all about 12
cleaned stepper
cleaned plenium
checked replaced vac hoses
timing set to 6 degrees etc

Am I missing something ? , I would appreciate any help at all towards figuring this out .

cheers
Damian from southampton

Remove plug 1 and check piston is at tdc with a probe. The bottom pulley might be lying.
Or have you already checked?

I think timing is ok ... I can double check .. would it not be hard to start if timing was out by a decent amount ? .. or enough to make it run as bad as it drives .? Cheers

It sounds too far retarded from your description.

Wonder if the distributor is knackered

freelance said:

Wonder if the distributor is knackered

Click to expand...

lack of mechanical or vac advance could be the problem

How about maf sensor... or throttle sensor? ... they have been mentioned ?

They need to work and be set correctly but from your description, unless you have a lumpy cam or it's not firing on all cylinders, you may have spark too late. This would cause a slow idle tick over and a little lumpishness as long has base idle hasn't been adjusted. As freelance says, your distributor could be suspect too. you need around 7deg btdc per 1000rpm so aldo look for 28deg btdc at 4000rpm with vac removed.
Here's a link for maf, tps, and all other hotwire settings
http://www.actproducts.co.uk/2011/l...n-system-–-installation-and-diagnostic-notes/u

Put new maf on today ... even worse ... does stall engine when unplugged so I guess works somewhat ..

Right ..... my issue is after putting strobe on every lead .. I have 2 leads that are irratic .... both are 2 up from front each side ..... on tick over and acceleration.... so ... I need to ?? ... slit my wrists ... !

Double Check you have them arranged in correct firing order, leads aren't touching each other or engine. I assume you set plug gap to 0.7 - 0.8mm max. Check spark plug terminals haven't come loose. Run it in the dark to check for sparks from leads shorting out

Gaps to plugs are all fine , I have checked leads a few times ... checked cap etc . Cleaned plugs ... so I am guessing if 2 leads are showing via a strobe light that they are not firing constantly even with not being attached to a spark plug that I am looking at anything pre plug to change? , whole distributor and double check new coil and look at resistor .... ?

Anything prior to distributor cap and it would be unlikely to manifest on same 2 plugs consistently.
I've got loads of spare ignition bits here if you want to pop round

Where are you located ? Cheers

Ah ... Durham ... just around the corner .... cheers .

So ..... distributer shaft moves up and down ... guessing due to rotary arm being forced off at some point .... conflicting stories as to how bad it could make it run if at all ???

Narrowing down ..... new distributer but it has an amp on the side ! .. old one just had a connecter with 2 wires .... Blue and red ..... attached new distrubeter and put red to red and black to Blue...... only sparked once then no spark on turnover of engine ????

Usually amp at fault with this symptom. The wires from your old distributor should go to a remote amp, usually mounted on passenger inner wing near coil. So can you confirm you havent wired the new amp to the old amp? You only need 1 or the other. The new piggy back amp needs to be fitted with heat sink grease smeared on where it mates to the dizzy, but if it was bought assembled it will be done.

Right got you ...I have a coil in the cab with a condenser next to it ... not seen another amp but will look when.I get home .... everything electrical is in a box in the cab .. cheers ..... so if I ran the new 2 wires to the coil ???

damiancorrine said:

. so if I ran the new 2 wires to the coil ???

Click to expand...

yes. I believe rpi engineering has wiring colour details for different variant dizzies on one of their pages