Hi all
let me give you a bit of history first
the 3.9 has just been rebuilt in the last 2 weeks
light hone , new rings big ends and mains some light porting to the cylinder heads
cyclone cam from real steal set up with 3degree retard or advance cant remember which with out my paper work which is in norfolk and im currently in nottingham
9.35.1 comp ratio running on tins
brand new plugs fitted , moroso spiral wound plug leads genuine cap and rotor arm new vacum on the dizzy
i have no air leaks n the vacum system the plenum has been sealed down aswell
my problem started after the build the engine ran on tick over lovely but as soon as we took her on a toad rest she was holding back no power and wouldnt rev under load after much deliberation a fist full of advance was put in to the dizzy and hey presto she was cured
ive since took the defender on a trip to nottingham which returned me 19.8 mpg so she must of been running ko at that time
now for the major problem i was getting sick of the idle being at 2k ish rpms when comeing to junctions due to the road speed sensor so i unpluged the stepper motor which cured the problem i spent a day running around with the plug off and all seemed ok , until i called in at a friends and noticed a rougher than normall idol so i reconnected the stepper , and reset the ecu by removeing the fuses from the loom
im now back to were i started huge back fire through the plenum chamber and no power at all shes holding back again ive taken the dizzy to bits and the advance retard seems i very good condition and is working ive had the multi meter on the throttle pot 0.33 volts which is good i assume and the air flow meter is set at 1.5 volts no matter were i put the dizzy adv or retard it wont pull its poping and farting im lost as to what to do next
i would mega squirt it but im skint so thats not an option at the minute
please help !
let me give you a bit of history first
the 3.9 has just been rebuilt in the last 2 weeks
light hone , new rings big ends and mains some light porting to the cylinder heads
cyclone cam from real steal set up with 3degree retard or advance cant remember which with out my paper work which is in norfolk and im currently in nottingham
9.35.1 comp ratio running on tins
brand new plugs fitted , moroso spiral wound plug leads genuine cap and rotor arm new vacum on the dizzy
i have no air leaks n the vacum system the plenum has been sealed down aswell
my problem started after the build the engine ran on tick over lovely but as soon as we took her on a toad rest she was holding back no power and wouldnt rev under load after much deliberation a fist full of advance was put in to the dizzy and hey presto she was cured
ive since took the defender on a trip to nottingham which returned me 19.8 mpg so she must of been running ko at that time
now for the major problem i was getting sick of the idle being at 2k ish rpms when comeing to junctions due to the road speed sensor so i unpluged the stepper motor which cured the problem i spent a day running around with the plug off and all seemed ok , until i called in at a friends and noticed a rougher than normall idol so i reconnected the stepper , and reset the ecu by removeing the fuses from the loom
im now back to were i started huge back fire through the plenum chamber and no power at all shes holding back again ive taken the dizzy to bits and the advance retard seems i very good condition and is working ive had the multi meter on the throttle pot 0.33 volts which is good i assume and the air flow meter is set at 1.5 volts no matter were i put the dizzy adv or retard it wont pull its poping and farting im lost as to what to do next
i would mega squirt it but im skint so thats not an option at the minute
please help !