WH Statesman LS1 running rough

[stockyvrcalais]

hi all, well i have replaced plugs (platinum), leads, oil, oil/air/fuel filters, even coolant but to no avail, car is sluggish and sounds like it has a miss sometimes in idle, and when putting the boot into it seems to bog down, i have just filled the tank with more premium and added wynns injector cleaner (the good stuff), anyone have any idea what else it could be? I have looked for vacum leaks and all looks in order, could it be the fuel pump perhaps? Any help appreciated thanks.

[accentstencil]

Maybe one of the coils. Just curious as to how much you paid for the leads.

[Niper]

check the fuel pump
i once had the same problem
you can use a fuel pressure gauge to check
there is a connector for the fuel gauge on the fuel rail
the prussure should be between 300-410 kpa
if not that is your problem

[jay_wr8]

Maybe one of the coils. Just curious as to how much you paid for the leads.

i am curios about the leads to, and what sort? cheers, sorry i cant help you

[DanVN]

When i replaced mine ended up costing me 200 bucks for a set of top gun leads from ricebarn, unfortunately i had no choice as nowhere else was open and i needed the car running

[accentstencil]

When i replaced mine ended up costing me 200 bucks for a set of top gun leads from ricebarn, unfortunately i had no choice as nowhere else was open and i needed the car running

The reason I asked is because apparently they are $50 each from Holden, which I find absolutely ridiculous for a lead which is about 6 inches long. Must be made out of some rare material.

[stockyvrcalais]

hey guys, yeh i paid $123.75 for the leads, they are NGK 8 mm from Burson, as for the fuel pressure, where would i be able to get a guage to check it? I've never done it before but im willing to have a crack at it.......

[stockyvrcalais]

ok well i took car to my mechanic, he says he just cant find anything wrong with it, so im at a loss to explain it....any ideas guys?

[Drewie]

Maybe a faulty O2 sensor, they seem pretty common on the LS1. Have a read of the link below, see if the symptoms match what your experiencing.

What Are Symptoms of a Bad Oxygen Sensor? | eHow.com

[stockyvrcalais]

thanks Drewie, yeh i did think about that, but the car isnt throwing out any fault codes so its a hard problem to find, will an 02 sensor show a fault code if its faulty? And yes the car does have some of those syptoms from that link, especially the hesitation.

[trav_304]

have you washed the engine lately if so there may be water in the coil packs apparently they just pull them apart and blow the water out. I just took the engine covers off and give them a blow with the air compressor and it fixed my miss.

[stockyvrcalais]

no i havent washed it, but i gotta tell you its starting to do my head in lol

[stockyvrcalais]

just a thought, what if the cat converter has stuffed itself somehow, could that be a possability? Remembering no codes are showing up....

[rb26dett]

I had a similar problem, was the O2 sensors and they were not showing any codes.

[stockyvrcalais]

im starting to think that way.....

[Farax]

i had a similar problem but it was gas related, my gas backfired forces the vacum rubber to go loose and yeah that made the car sluggish and rough on idle. i just popped the hose rubber back on properly and it was all good.

[stockyvrcalais]

well i just fitted new 02 sensors all to no avail, im at a total loss now, any other suggestions guys?

[jay_wr8]

i've got a similar issue, i've got a rough idle and a miss, as for it been sluggish i'm thinking this is how the ls1's are, i'm gunna try get my mechanic to check it out this week so i'l let you know if he finds anything, i'm thinking i have a broken engine mount but that doesn't explain the miss, maybe also the injectors need a good clean

[rb26dett]

Try a new fuel pump and filter also.

[stockyvrcalais]

jay_wr8, yeah keep me posted im very interested to to hear what your outcome is.

[stockyvrcalais]

rb26dett, yes i thought about that, but everyone including my mechanic tells me that fuel pumps either work or they dont, so i dunno.....

[stockyvrcalais]

well im thinking about getting my injectors cleaned, anyone know of a reputable place around melbourne northern suburbs?

[motox75]

it will b a coil pack just had the same prob took ages 2 sort it but thats all it was.

[stockyvrcalais]

wouldnt a stuffed coil pack throw up a fault code though?

[motox75]

no iv got 2 scanning tools one is just a obd reader and the other is a complicated scaner werth thousands and neither of them picked up my dead coilpack.