I have a gremlin in my GQ and I can't find it!

[taslucas]

If it is happening more when it's hot it may be coil, balast or points related. A faulty coil will break down as it warms up. Although I did read you said they're all good.

[Goyney]

Thanks again fellas.

A few more things I have figured out,

Since it is happening on both fuels that rules out the mixer and the fault seems to be identical on both fuels so
I am leaning away from it being a gas problem.

It is running really smooth at all speeds above idle and 80% of the time at idle.

One thing a buddy mentioned was although it does not have a MAF sensor, he said it does have a sensor of sorts
in the air intake? I'm not too sure on this one but there is a sensor of some sort I can see and wondering whether
I should clean this out? It has an airline going to the carby and is pretty dirty! Attached is pic

photo.JPGphoto1.JPG

[Goyney]

theres about 4 million things that it could be. but my father inlaw had a gq come in once with the carby loose and only held by one bolt. needless to say that ran (amazingly) pretty average. its amusing to see that as soon as theres a problem with a gas car everyone assumes thats its the gas. lol. Im guessing its prob an air leak somewhere since its both fuels. id run the gas from an oxy over your inlet while its running see if it changes revs and id move everything a little see if it helps find the problem. could be an old cracked hose or blown gasket. on another thought has it backfired cos thatl break stuff too.

Cheers Warner. No backfires as yet. The air intake definitely looks like it is not 100% sealed, the mechanic was saying this would not
cause the problem though?

I had that exact problem with the carby in the past and you could literally move it around and watch the car run from smooth to rough! Carby has been rebuilt since then.

[mudnut]

That is the Pre-heat flap. Gives warm air to the carby to heat up the system faster. I think there is a bi-metal strip in the filter housing that opens and closes the vacuum hose to the diaphragm. (RB30 does so I assume the TB42 must also). The MAF is for fuel injected engines, it provides airflow data to the ECU.

Also check the wiring to the gas/petrol changeover switch.

[Goyney]

Hey fellas,

Another update. The gremlin is found....

Took it back to the mechanic and he fixed the problem, ignition condenser!

She now runs sweet......but now will not run on gas! Only discovered this today after trying to switch over.....It was running before.

I had a quick look at the Coil and ballast resistor and he has re- done all the wiring but missed a lead.

As you can see I am sure this is why It won't switch to gas. The lead goes through a fuse to solenoid then to the mixer.

There is also a terminal on the coil which I am sure was made for the lead however when I hook it up it won't switch!

I checked the fuse and it looks a little old and corroded, so I tried a slightly higher amp fuse I had lying around but this didn't work

Any ideas?

IMG_2405.JPGIMG_2406.JPG

[threedogs]

if it is switching and not firing on gas it could have an air lock I had this prob if I let the gas run very low then re fill'
Check the filters in that bit in the photo. Check and re do a few earths as well

[Goyney]

if it is switching and not firing on gas it could have an air lock I had this prob if I let the gas run very low then re fill'
Check the filters in that bit in the photo. Check and re do a few earths as well

Thanks for the reply mate, it was very low before I put the car in so that could be it, is there a way to get it to fire?

[rimshot]

.if its bad when its hot have a look at the dizzi. I had this prob with another car. Run good cold but like crap some times when hot.

[GQ TANK]

Put a volt meter across the gas solenoid - get some to click the ignition - the meter should show 12 volts.

There are probably 2 gas related solenoids under the bonnet - one on the mixer and one on the gas filter probably near your fire wall.

There should be a lead from the NEGATIVE of the coil going to the gas safety switch. The switch needs to see the pulses from the points - or it will turn the gas solenoids off._ sw