Confused.

[Redy]

Hey guys

i am a bit confused with my car, 1 mechanic says one thing another says something else maybe you guys can help lol

my car has been playing up sounds like its backfiring through the carby and it sounds like its slightly missing as well, i took it 2 the mechanic that i have been taking it 2 since i got the car, he said transmission fluid was getting into the motor cause the modulator was broken thus meaning the car would not run good,

so i got a recondition gearbox off ebay for $72.00 i thought wow as i have heard they can go for $700 apparently, the guy i got it from is a mechanic for lube mobile and said he was hoping to get more but what can u do he has to move and needed it out of there, he put it in for me aswell for $100 dollers anywho that fixed the modulator problem, but its still missing and backfiring

he said that it was my holly he couldn't tune it properly he said he spent ages fiddling with it and couldn't get it right he suggested i put a vari-jet on there that he had.

but the thing is the mechanic that i had taken it to all a long had it running really well and all of a sudden it done this missing and backfiring.

my mother also heard on a car forum(might of been this 1) that these vk's have a computer and need to be timed with that and not with a timing light as the timing will just go back to what the computer is set at, which makes sense as it has been timed with a timing light number of times and just goes back to missing, but i am not 100% sure if it does have a computer. also i think the holly is letting to much fuel in as the machanic i got the gearbox from said unburned petrol is coming out of the exchaust, which i think i could just get smaller jets, not sure of the number on the jets will have a look tomorrow.

sorry about all this reading but i thought i would let ya's know everything, any suggestion is appricated

thanks once again
Jade.

[2DIE]

Does it have a steel or plastic float in the carby?

Sometimes the old steel ones get a tiny pin hole in them and always cause the carby to flood/backfire.

The plastic replacment is $10 or so.

This happend to my brother a few years back and he kept going to different mechanics all over the place, took him about 10 goes to find the problem.

[Redy]

oh thanks mate i'll check tomorrow which i have, and if so do i just go to super cheap or something and ask for a replacement float from a carby?

[Jacko84]

why didnt you just put a new modulator on it

[rockerpeller]

$72 is pretty good for a reco box. I would've gone the reco box before just the modulator myself.

[Redy]

Yeah i got the reco box got it put in for 100 dollers.

[VK SL 3800]

TO see if it has a computer or not just look at the distributor and if there are no wires running to it except the wire from the coil to the cap then its got a computer, if it has a few wires running off it then it doesnt. Only VK commodores with a 6cyl carbie had computers dont remember reading which model yours is. Most VKs with computers have had them removed or disconnected and had a VH electronic dizzy fitted instead.

[Redy]

ok im pretty sure it only has that wire going from the coil will double check tomorrow, and its a black 202 motor carby

[Tree cutter]

Could be a leaking power valve diaphram on your carby.

[Darren_L]

if someone has already swapped an earlier model distributor onto the engine, then you will see a small silver box (ignition module) attached to the body of the distributor with wires coming out of it. If it still has the EST distributor, it won't have the small box.

if the engine still has the EST (electronic spark timing) distributor hooked up, and it has a Holley fitted, then chances are you don't have a throttle position switch hooked up, which is necessary for the EST computer to calculate spark advance correctly.

Easiest fix in this situation is to replace your VK EST distributor with VC, VH blue motor distributor & bypass the EST

[Redy]

Ok well i know it has a ignition module cause the mechanic had to get a new 1 for me as the old 1 was forked, and the coil has 2 wires coming from each side of it going to the distributor, as for the EST and holley being hooked up i am not sure as i don't know what has been done to the car b4 i got it,

but as for my car it is running really well now for some reason, not missing or backfiring, it just seems a bit out of tune or timing, but i can't really even notice it. or i think its just the flat spot in the carby, not sure if i can get rid of that or not.

[Redy]

was just wondering what is the main causes for backfiring?

to much fuel to the carby? havn't been able to check that float yet, have to do it wednesday, if its still raining here in qld have to make room in the shed lol

timing out? the mechanic that put my gearbox in said he timed it so ####s me

i know i have to change my rocket cover gasket (head gasket?)

also with that lead replacement additive stuff is that of much importance if u only use vortex 95.98? cause 1 mechanic said if i only use that i don't have 2? but if i do i'll put some in lol

[Redy]

still missing a bit, not sure if its my plugs or carby or what now taking it to a carby specialist tomorrow

[tha goviner]

my old 202 had the same problem i changed the carb and distributer changed ended up being the head out of wack by a few thou and the gasget was gone between 4 and 5, found out later this is common when the head gasget go's, and one other thing have ya checked all the vacume hoses as one might be loose or off and causin all the problems