6.8 ohm resistor

General Chat About Electrics, And Ignition Systems.

Moderator: phpBB2 - Administrators

Post Reply
dusty
Newbie
Newbie
Posts: 5
Joined: Sun May 18, 2008 7:04 pm

6.8 ohm resistor

Post by dusty »

checking out ecu wiring on my 3.9 hot wire . rebuilt engine over fueling. all plugs black. found idle valve not working and replaced replaced. ignition wire to ecu with resistor is giving 7.2 ohms is this within tolerance.
engine starts fine and runs but lacks power when gven some boot .


User avatar
Ian Anderson
Forum Contributor
Forum Contributor
Posts: 2459
Joined: Sun Nov 19, 2006 9:46 pm
Location: Edinburgh

Post by Ian Anderson »

Hi Hotwire goes into fault mode for a get you home thing.
Basically it goes slobbery rich so as not to damage thisngs with too lean engine

But it's easy to reset

Disconnect the battery for 30 seconds - and reconnect it - no more error codes in it's memory!

Hell I even have a battery isolation switch fitted in case mine goes into this mode! saves getting the spanners out

Ian
Owner of an "On the Road" GT40 Replica by DAX powered by 3.9Hotwre Efi, worked over by DJ Motors. EFi Working but still does some kangaroo at low revs (Damn the speed limits) In to paint shop 18/03/08.
Will Reeve
Getting There
Getting There
Posts: 257
Joined: Fri Jun 04, 2010 8:22 am

Post by Will Reeve »

The extra resistance is probably the resistance of the wire to the resistor.
ramon alban
Knows His Stuff
Knows His Stuff
Posts: 667
Joined: Fri Nov 17, 2006 11:22 pm
Location: Bedford UK
Contact:

Re: 6.8 ohm resistor

Post by ramon alban »

dusty wrote: ignition wire to ecu with resistor is giving 7.2 ohms is this within tolerance.
Hello Dusty, could it be the resistor with WB wires indicated on this diagram, or a similar ignition set-up?

Image

In which case its design value is 6,800 ohms and your 7,200 ohms (?) with 400 ohms difference is well within the normal 10% tolerance for these type of components. Its even close to 5% which is also another typical benchmark in electronic design tolerance. So no worries! :D

To be sure we are on the same wavelength verify you are not misreading the 'range' of your multimeter when measuring.
Will Reeve
Getting There
Getting There
Posts: 257
Joined: Fri Jun 04, 2010 8:22 am

Post by Will Reeve »

missed the "k", as wire resistance is usually under an ohm it's irrelevant here! Sorry for the mislead!
dusty
Newbie
Newbie
Posts: 5
Joined: Sun May 18, 2008 7:04 pm

6.8 resistor

Post by dusty »

thanks for the replys. thats ok on the resistor :D . I have been disconecting the battery every time to clear ecu . engine also has a new cts and fuel regulator. tps checked out on ohms. do you think a different ecu will be worth a try :?:
User avatar
richardpope50
Gold Member
Gold Member
Posts: 616
Joined: Thu Jan 28, 2010 12:25 pm
Location: Horsham, West Sussex

Post by richardpope50 »

PM me your e-mail address if you want the Land Rover Hotwire ECU test manual.
Richard.
Dax Rush 5.0l TVR V8, EFI with Megasquirt ECU and wasted spark, Racelogic Traction Control and Quaife LSD ....... Now nut and bolt restoring a TR6
Post Reply

Return to “Electrical & Ignition Area”