TB42 electrical gremlins troubleshooting help

[4by4roar]

hello everyone!

I've recently caught the off road bug and bought a 94 GQ Patrol TB42 efi dual fuel.
She was running like a dream for a week of around town driving until i took her in for a roadworthy inspection where she suddenly developed an intermittent running issue (Murphy's Law).

Symptoms:

at the mechanic i had to crank her for around 5sec before itll start and when she does itll miss and run ruff as. the taco goes haywire (which makes me think electrical), check engine light is on and its under powered and stalls.
let her sit for 5mins and shell start no problems, runs okay with no missing for a few kms then suddenly dies with no popping or spluttering. let her sit for 5-10mins and repeat.
the problem is on both fuels.


ive changed the ignition coil and power transistor, cleaned contacts and grounds with no success. i have a few ideas on where to look next, im thinking that it might be a problem with the duel fuel system freaking out and cutting power to the coil. i havent been able to measure power to the coil as it dies but my gut is telling me thats where the fault is.

i was wondering if anyone has had similar problems or any insights into things i am missing. help would be greatly appreciated, im eager to get exploring! this vehicle-less isolation is driving me crazy haha

cheers!

[mudnut]

Welcome to the forum. Please head over to the introductions and say G'day.

Dual fuel can be a nightmare, depending on the the quality of the work done when being installed. Check the battery terminals, the wiring loom and connectors, especially at the coil. If it is common to both fuels, check the wiring, the selector switch and for any in-line fuses.

http://www.nissanpatrol.com.au/forum...-rough-running

[the evil twin]

Given it is an LPG conversion that sounds suspiciously like a Tachometric Relay fault to me.

Depends on the conversion so I'm not all that confident it is the culprit but would def be an ignition circuit component to eliminate.

[4by4roar]

Cheers mate! ill give it a look

im just at a loss as to what could be causing an intermittent fault like this.

[threedogs]

It may be dual fuelling so X2 with a trip to the specialist.
if its an old system it may require a kit for the condenser.
Maybe source an electronic ignition system, , keep us informed please