05-25-08, 03:15 PM
I have a 1993 Allante with a 4.6 Northstar engine and 64k on the odometer. This is my 2nd coil to go out in less than 1000 miles so I'm thinking the AC Delco coils are at the end of their lifespan and I need to replace them all. Should I install another brand of coil such as MSD or Accel or is it just a waste of money? I want a coil that has a longer lifespan.
Here are some coils that Jegs sells for our cars
After the 1st coil took a dump, I installed MSD 8.5 mm wires so would MSD coils compliment these wires?
05-26-08, 10:21 AM
I can't speak directly for the Allante` but the general rule of thumb around here is that the AC Delco coils are more than sufficient and that aftermarket coils are a waste of money.
My 01 doesn't have wires of course but if / when I do the coils I'm going to stay with GM. There's a lot of reading around here on that subject, but I think it's pretty unanimous.
05-26-08, 02:06 PM
Well, the price of MSD coils is priced lower than AC Delcos and they also come with a 1 year warranty. I'm also having a problem with coils burning out so I think I may go with this option.
The other option I might go is to buy the cheapest coils I can get (Standard Motors $19.94) and keep several extra coils in my truck to replace as they burn out.
05-26-08, 07:14 PM
Very curious. Ignition coils should last literally forever unless they are either constantly wet or soaked with engine cleaner. Maybe, just maybe, aftermarket high resistance secondary wires could come into play, but that's pretty remote.
There is no reason to remotely consider burning out a coil at 64K. Something's wrong.
05-26-08, 09:09 PM
Yeah I have to agree with that. Those OE coils are designed to last a lifetime, literally. unless you break them you should never have to replace them.
Good point on the wires but I would say something is definitely wrong.
05-26-08, 09:39 PM
Well, the first coil burned out with the original AC Delco wires. I installed new wires because of extremely rough idle and sputtering when going up hills and low rpms. The new wires fixed the sputtering but not the rough idle. The idle has degraded to the point that it quits at every stop light unless I put the transmission in neutral and keep my rpms above 1000 rpm. It's also a random misfire at idle. Yesterday after about 5 minutes of driving, the 2nd coil burned out. This was confirmed by removing each spark wire 1 at a time and finding the coil that does not produce spark for 2 of the cylinders.
Could my ignition control module be eating the coils?
05-26-08, 09:53 PM
I would suspect. That after 15 years, some internal components materials must be breaking down. Hence the coil failures.
I have never heard of this trend on a Northstar. Not many running around with 15 year old coils.
We have used aftermarket coils with no problems.
That being said, I seem to have multiple coil failures on lawn equipment. Last couple of years had a coil fail on a LawnBoy mower, and a coil puke on a Homelite blower.
Logan Diagnostic LLC
05-30-08, 05:21 PM
For the rough idle, have you ever cleaned your throttle body? Follow this procedure:
If you haven't done it, at 15 years you're way overdue. And make sure you clean the idle assembly while you're cleaning.
Do you have any stored codes?
Pull the codes and tell us what you have stored.
06-03-08, 02:44 PM
Thanks for the replies:
Yes, I did clean the throttle body and mouse holes about 2000 miles ago. There was some carbon that I cleaned out but nothing major. The car was running good at that time and the procedure did not make any difference.
The problems actually all started when I stored the car for 6 months without driving it. It has been very difficult to figure out what is wrong because I have had no codes pop up. However, I have ordered 4 used A/C Delco coil packs and a used ignition coil module. It should come in next week so I'll put in these parts and see if it fixes the problem.