2.7mpg, extreme poor running!!

[dirtydiscov8]

Update!!!

So it's not the ecu it seems to be running horribly rich on the left bank ( 2,4,6,8 ) because....there is hardly any spark at the plugs! Theres enough to light up ht lead testers but not enough to make a timing light strobe!

Any ideas what could cause one bank to have a very weak spark but the other bank to be fine?

Leads, cap, plugs etc have all been checked and swapped where i could.

It's a Mallory magnetic breakerless dizzy with the correct mallory coil and ballast resistor.

Happy Crimbo!!!

 

[lorri789]

stumped

 

[fett]

not had much luck with Mallory, get quality spares for them is the issue- but you cant!

 

[dirtydiscov8]

not had much luck with Mallory, get quality spares for them is the issue- but you cant!

I can get the spares but i don't want to go buying things i don't need. Really poor spark on one bank only and fine on the other! That's just odd. Nothing in the ignition system even knows which bank is which!

The Dizzy cap is the type held on with two screws not clips so i can remove and spin the cap 180 the re-fit the leads see if that changes anything

 

[fett]

I would bin it for a standard unit, even if just to test.

I would be impressed if you can get quality spares for it btw because my mate has tried everything and gone back and fitted a lucas!

 

[Mr Noisy]

hmmmmm. gonna be a complete berk and say earths. just that for some reason my engine had an earth strap on one of the heads, but i have removed it cos it seemed pointless!

its a truly stupid thing to say but sometimes you have to look at the stupid stuff first!

 

[dirtydiscov8]

hmmmmm. gonna be a complete berk and say earths. just that for some reason my engine had an earth strap on one of the heads, but i have removed it cos it seemed pointless!

its a truly stupid thing to say but sometimes you have to look at the stupid stuff first!

I was also thunking it could be an earthing problem. The efi harness earths to the back of the heads originally doesn't it?

Looking at it tomorrow so i'll report bac

 

[Mr Noisy]

my efi harness was not earthed anywhere other than the OSF wing where it meets the earth lead from the battery on its way to the chassis. sensors and injectors are earthed back to ecu so the efi itself doesnt much care for engine block earths.

there is not any reason why one bank could have a bad spark other than a huge fluke with bad plugs/leads/etc or some some wild wild impossible reason there is a bad earth at the OS head.

even thinking about it is daft, its impossible basically.

 

[jamesmartin]

my efi harness was not earthed anywhere other than the OSF wing where it meets the earth lead from the battery on its way to the chassis. sensors and injectors are earthed back to ecu so the efi itself doesnt much care for engine block earths.

there is not any reason why one bank could have a bad spark other than a huge fluke with bad plugs/leads/etc or some some wild wild impossible reason there is a bad earth at the OS head.

even thinking about it is daft, its impossible basically.

which should be earthed on back of lh head (ecu)

 

[Mr Noisy]

my 14cux definitely did not have an engine block earth.

the earth strap on my NS head went to the body just near the NS bonnet hinge.

i removed this because i dont like earth straps as i believe they are stupid.

i have the main earth from both batteries to the chassis and then to the engine block at the top starter motor bolt, which in turn earths the gearboxes/axles etc etc.

 

[jamesmartin]

there is usually 2 pairs of black wires to earth the efi from efi loom,ecu isnt earthed and doesnt need to be

 

[Mr Noisy]

yeah im pretty sure the earth point at the OSF arch was a pair of say 1.5mm or 2.0mm black wires.

of course the ecu is earthed! it switches the injector earths for one thing!!

 

[jamesmartin]

through the black wires ,it will still run with ecu sat away from vehicle obviously wires dont need to go to head just earth but thats normal position

 

[Mr Noisy]

right yeah well, by 'ecu' i meant the ecu board not the casing!

for reference anybody, engine block earths are awful so it is far preferable to earth and ecu to the battery!

maybe flappers were earthed to the engine and hotwire to the battery?

in all honesty i have zero historcal knowledge of other installs, i just know what i know...

 

[jamesmartin]

right yeah well, by 'ecu' i meant the ecu board not the casing!

for reference anybody, engine block earths are awful so it is far preferable to earth and ecu to the battery!

maybe flappers were earthed to the engine and hotwire to the battery?

in all honesty i have zero historcal knowledge of other installs, i just know what i know...

ive less experience of flap but all hot wire earth to rear of head with 2 pairs of black wires coming from efi loom ,they are the only earths in the efi system ,so those must be what you put to the battery

 

[fett]

it dont matter for you now noisy

 

[Mr Noisy]

ive less experience of flap but all hot wire earth to rear of head with 2 pairs of black wires coming from efi loom ,they are the only earths in the efi system ,so those must be what you put to the battery

odd! maybe they had a rethink when they built my car cos there's no way they were supposed to be for the engine in that loom.

ANYWAY there you have it

 

[Mr Noisy]

it dont matter for you now noisy

ahhhhhhhhhhh just got back from a laning trip up north yorkshire and it was ridiculously wet, impossibly wet in fact, it was incredible, totally tropical!

the MS was fabulous, it's just wonderful now, SO worth it!

 

[fett]

glad its workin for ya bud, watch out for those zombies

 

[Mr Noisy]

thanks john, yeah monster relief tbh.

cant recommend it enough, thats all im saying on the matter basically!

what zombies??!