Advice please!

[SWE11L]

I have a rough idle and plan on replacing spark plugs and leads, as they havent been changed for years, and the coil packs. Ive read that MSD are the best after market for leads and coil packs, but quite expensive, does anyone know if they really make a difference? Also been told to get 'iridium' spark plugs. Any advice would be appreciated.

[The1]

just buy standard plugs and leads first, standard holden plugs work fine, bosch leads are pretty good to, for the money spent you get no return on fancy plugs and leads, coils etc, msd coils are no different that a normal coil, if there's an issue with a coil generally buy one coil pack or borrow a working one and try all 3 spots soon find which ones causing the issue. If it's still playing up after that and your sure it's a spark issue replace the DFI board under the coil packs.

Also have you ran a error code check?

[brinz96VS]

In regards to iridium spark plugs the main advantage is they last longer, which is great if you cant be bothered renewing them for 60,000 k's +
However they are not an inconvenience to change on the commodores so id just stick with the standard plugs and save some money.

[hsv91ss]

I got a set of 6 Bosch Platinum/Iridium Ir-Fusion plugs direct from the US, since our ecotec/L36 is the same as theirs apart from the intake manifold. Paid $58AU Delivered by International Express Post from Redrock auto.

They are a good plug I noticed a smoother idle, smoother acceleration and slight increase in economy, however they are no super plug but worth the extra if your after a long life plug.

But that is just my opinion, there is nothing wrong with the copper plugs.

[som]

there are other good products out there but for the money and for good plugs and leads go genuine.

[bpefi]

I found genuine leads to be better than Bosch by far - the insulation cracked & leads kept falling off - so I took them back - also been told platinum plugs no good for LPG by my installer - never heard of that one before. Found the Pulstar plugs to be fantastic (look up on youtube or google) but dont last as long as they claim.

[SWE11L]

just buy standard plugs and leads first, standard holden plugs work fine, bosch leads are pretty good to, for the money spent you get no return on fancy plugs and leads, coils etc, msd coils are no different that a normal coil, if there's an issue with a coil generally buy one coil pack or borrow a working one and try all 3 spots soon find which ones causing the issue. If it's still playing up after that and your sure it's a spark issue replace the DFI board under the coil packs.

Also have you ran a error code check?

I had it checked for errors a few weeks back and nothing came up.

[Brett_jjj]

I had it checked for errors a few weeks back and nothing came up.

You can actually check these codes yourself,you dont have to get someone else to do it.Its simple to do.Heres a link to a "how to"..
---Checking error codes VR/VS (Revised)---

[SWE11L]

Hi people, Today I changed my leads and plugs and although I do notice it starts quicker and better acceleration, the idle has actually become much worse. Also, possibly unrelated, I havent driven it since saturday and when I took it out for a drive to test the new stuff tonight, my breaks are really wierd, like there is no power assistance... had a new break booster put in bout 3 years ago... can anyone give me their 2 cents??

[The1]

if it's really ruff you could try pulling off each spark lead, when it makes no difference it's that coil that could be faulty, try then swapping the coils around and see if the fault follows the coil if it does replace the coil if it doesn't could be the dfi board under the coil packs. Usually a spark issue will be worse under load with acceleration not at idle. With ya brakes is your vacumme line to the booster all good? Got good fluid level? when was the brake fluid changed? Should be ruffly every 12months as moisture builds up in the fluid.

[Clutchy]

Maybe ya havent put the lead on a plug far enough ? and as for the brakes that might be a flow on effect not runnin rite might give the brakes a lack of vacuum.

[hako]

I'd say the bad running and the brake problem are both the same....probably the vacuum line is off the manifold and air is entering the inlet manifold causing the running problems. Running rough will not cause loss of brake as your engine will still produce a vacuum when it's running...
Check the vacuum line(s). Good Luck.

[SWE11L]

Hi guys, just got back from losing pub trivia! Decided to check some of your suggestions and upon checking my brake booster i noticed a filthy big crack through it running vertically above and below where the hose connects to it, i know this is causing the brake problem but would it also relate to the rough idle?

The rough idle has been around for about 6 weeks now, but when i drove the car last (4 days ago) brakes were fine!

Could the crack have appeared a while ago and been too small to noticably affect the brakes but enough to affect the idle and gotton bigger to the point where the brakes are now powerless and the idle is suffering more from a growing crack??

[SWE11L]

With ya brakes is your vacumme line to the booster all good? Got good fluid level? when was the brake fluid changed? Should be ruffly every 12months as moisture builds up in the fluid.

yeah booster is rooted mate, see my photo! Fluid level is good but not been changed for a while... putting the beast in for a major service (200000km is overdue) so ill have em change that.

[SWE11L]

I taped up the crack to test and idle's beautifully and power back to the brakes!! Cheering! New booster tomorrow, at least its safe to drive down to the mechanics now. Thanks for all the help!

[hako]

Nice to see a result!! That 200000km service is going to be expensive!

[SWE11L]

Nice to see a result!! That 200000km service is going to be expensive!

New booster in today, running great! How much do u reckon for that service? Probably quite a few things to replace huh?