R50/53 Rough idle after pulley upgrade
Rough idle after pulley upgrade
I had a 15% pulley installed along with upgraded plug wires at MOTD. After I replaced the std. NGK plugs with the new Brisk plugs ( a bit cooler plug), the car now idles a bit rough and seems to skip a beat at idle, while also stumbling a bit when cold. I have read that a new coil pack MSD or Screaming Deamon has helped resolve these types of issues. Before I drop close to $90 on a new coil, is there any feedback that this is the correct path, or am I better off to go back to the original plugs that gave me no problems on the 1,000 mile ride back from NC.
Last edited by JIM_GRAHAM; May 17, 2009 at 04:48 PM.
Double-check that you used the correct Brisk plugs (one range colder than stock, max), and that they're gapped properly. I wouldn't start off by throwing in a new coil pack, because the factory pack is a pretty capable unit. There are quite a few MINIs running around on the factory coil pack & wires that are modified *way* beyond a simple 15% supercharger pulley.
I verified that the "DR12S" Brisk Plugs are the ones recommended for use w/ 15% or > pulleys via Alta's Web site. The gap was set at .028 at the MOTD, but I did not verify that when I put them in when I returned home. It was suspected that my coil had a hot spot on #3 due to some discoloration of the lead. I ran the stock NGK's with the new wires and original coil on some pretty spirited drives on the Dragon and then all the way back to NH at 80 mph with no problems. I actually got 1.5 mpg BETTER gas mileage with the pulley and new wires then on the way down.
Any feedback on the preferred gap for those type of plugs? I will try resetting the gap to see if that clears things up before going back to the original plugs to see if that corrects the issue.
Any feedback on the preferred gap for those type of plugs? I will try resetting the gap to see if that clears things up before going back to the original plugs to see if that corrects the issue.
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From: Car Nut Since 1987, Owner Since Fall 2005, Vendor Since Fall 2007
HI Jim, I recall our visit at MOTD and we encouraged you to replace the coil with an OEM before installing the BRISK plugs due to that #3 hot spot. Please out the NGK back in until the coil is replaced. I encourage the OEM or OEM replacement coil.
I came away thinking that a coil upgrade was necessary. My bad. I figured if an OEM coil was servicing the NGK's ok, then an upgrade was needed to handle the upgraded plugs.
Fortunately, the OEM MINI pack is more than capable of working with the increased pressure. In fact, there are quite a few MINIs out there putting out 250 or 300 horsepower with the OEM pack and wires.
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I'm experiencing the same problem but worse
I had a 15% pulley installed along with upgraded plug wires at MOTD. After I replaced the std. NGK plugs with the new Brisk plugs ( a bit cooler plug), the car now idles a bit rough and seems to skip a beat at idle, while also stumbling a bit when cold. I have read that a new coil pack MSD or Screaming Deamon has helped resolve these types of issues. Before I drop close to $90 on a new coil, is there any feedback that this is the correct path, or am I better off to go back to the original plugs that gave me no problems on the 1,000 mile ride back from NC.


Update
I test drove it right after and my car was driving 100% better than it was. I was shocked at how hard the car pulls at the 2-3k rpm range. This fix lasted for about 10 days, then I noticed in very hot weather my car progressively started to feel like it did before. I haven't changed my plug wires yet or the coil pack. I think they are both the original since 2003. Now my car runs like crap again.
Do you think that either my coil pack or plug wires could be faulty? How can I tell?
I have read that the coil terminals are prone to corrosion. I was told to get an OEM coil which priced out at $115 + shipping, when I looked, so I purchased (from OutMotoring, they had it in stock when I called and shipped that day):
31732M 100-025Screamin Deamon Ignition Coil Pack $84.95 Subtotal: $84.95 Shipping cost: $16.70 Total: $101.65
This has addressed the rough idle and skipping problems. The instructions stated to set gap at .065 +/- (I am not reading them at the moment) which I have not done yet. I still get a brief stumble while the engine is cold but it goes away in a couple of minutes when the engine warms up. I am going to experiment with the gap to see if that goes away soon.
31732M 100-025Screamin Deamon Ignition Coil Pack $84.95 Subtotal: $84.95 Shipping cost: $16.70 Total: $101.65
This has addressed the rough idle and skipping problems. The instructions stated to set gap at .065 +/- (I am not reading them at the moment) which I have not done yet. I still get a brief stumble while the engine is cold but it goes away in a couple of minutes when the engine warms up. I am going to experiment with the gap to see if that goes away soon.
You should e able to pick up a gap ring/tool or a set of feeler gauges at a local auto parts store.
As far as the gap, that is plug/car specific and you will have to do some research depending on what you have.
As far as the gap, that is plug/car specific and you will have to do some research depending on what you have.
My $.02
Stock plug wires are very good but at $30 each (quoted by the dealer) not the set, it pays to use aftermarket if needed.
I have found that with extreme care in removing and replacing the stock (or aftermarket) wires, some damage does occur each and every time.
I would replace the wires and all the other issues may be taken care of.
I have found that with extreme care in removing and replacing the stock (or aftermarket) wires, some damage does occur each and every time.
I would replace the wires and all the other issues may be taken care of.
I'm not sure what to buy?
I noticed that some recommendations were to replace my OEM coil pack with either the screamin demon or msd? Also what are the best plug wires to go with? Does this hessitation definately have somethin to do with my coil and wires?
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