MSD Cap and Rotor

**Injuneer** · 06-27-2017, 11:26 AM

Checked w/ BLUEDEMON95 and still has not installed rebuilt MSD unit. He apparently had been using the F-Body as his daily driver, and couldn't take it out of service. But now has alternative ride, so will install it shortly.

**Spudnick** · 07-06-2017, 08:16 PM

I posted a thread on LS1Tech, but I'll add info here too since this seems to be a widespread issue. I had my original MSD opti, 9 years old, that the rotor screws backed out and the rotor detached. Sent it into MSD to make sure it wasn't damaged and it looks like they sent me a brand new opti minus the pigtail to the wiring harness (I know it was my old harness since the little gray retaining clip was broken off when I sent it to them). Put it in the car and it seemed OK, but I noticed a slight miss at 2400rpm. Started it up a week or two ago and the idle was horrible, jumping from 1000 to 1500, 2000, down to 7000 etc... My data logs show what the others have said, there is a split second spike where the rpm shoots way up with no throttle input.

I'm calling MSD tomorrow, but I am half tempted to get another opti in the meantime. I have already spent half the summer with the car not running and I've spent some money replacing other parts that apparently weren't the issue...

**BALLSS** · 07-06-2017, 08:49 PM

Rotor screws backing out is not uncommon for any brand Opti/ Whatever Opti you do get, remove the rotor screws and use Blue Loc-Tite on the screws that hold rotor on

Yeah this and a few other threads note what seems to be a broad issue with the MSD Optis over the last year or so. Ironically if you had kept your 9 year old one and just bought a new MSD cap & rotor you would have been fine as that Opti worked otherwise for a long period. You likely got one of the newer inventory units that seem to be problematic with from my understanding not a clear "why" as to what the problem is. I think MSD is focused on the optical sensor they use

**SSlowBoat** · 07-06-2017, 10:36 PM

Originally Posted by Spudnick

I posted a thread on LS1Tech, but I'll add info here too since this seems to be a widespread issue. I had my original MSD opti, 9 years old, that the rotor screws backed out and the rotor detached. Sent it into MSD to make sure it wasn't damaged and it looks like they sent me a brand new opti minus the pigtail to the wiring harness (I know it was my old harness since the little gray retaining clip was broken off when I sent it to them). Put it in the car and it seemed OK, but I noticed a slight miss at 2400rpm. Started it up a week or two ago and the idle was horrible, jumping from 1000 to 1500, 2000, down to 7000 etc... My data logs show what the others have said, there is a split second spike where the rpm shoots way up with no throttle input.

I'm calling MSD tomorrow, but I am half tempted to get another opti in the meantime. I have already spent half the summer with the car not running and I've spent some money replacing other parts that apparently weren't the issue...

yep, sorry man. same thing happened to me. returned it 3 times only to have the same issue every time it came back. I sent them a working fine opti and got back an ash tray.

go figure, my Amazon opti is working great *knock on wood*

Sent from my SAMSUNG-SM-G935A using Tapatalk

**captainofiron** · 07-07-2017, 08:56 AM

My opti is in El Paso right now getting looked at, not for a spike, but a closed loop/hot idle misfire

Mine was rebuilt in 2014 and had max 1500 miles on it

post link

***popo8*** · 07-07-2017, 10:38 AM

Originally Posted by captainofiron

My opti is in El Paso right now getting looked at, not for a spike, but a closed loop/hot idle misfire

Mine was rebuilt in 2014 and had max 1500 miles on it

post link

Do urself a favor. Just sell it amd go delco. Im sorry, I fought it for a long time, thinking the cost and name meant it was good... but it wasnt.

Im not only an LTXtech member... Im also the Owner.

**Spudnick** · 08-21-2017, 02:34 PM

I got my MSD opti back again today. Repair sheet says that the optical sensor was replaced with an updated one to correct noise issues with the cap. Also looks like they replaced the cap as the one I sent in had a scratch on it. I won't be putting it on my car though since the Summit opti I put on has been running like a champ. I'll probably keep it as a backup.

I'm curious if anyone received theirs back recently with the new sensor and how its working...

**Stormyweather** · 12-30-2017, 05:47 PM

So after all this time the summit opti is still the one now? Being that my w/p was leaking at the flange and Im there any way. Im thinking of opti as well. Any incite would be nice thanks. Cause MSD isn't? right?

**95mysticta** · 12-31-2017, 04:54 PM

Originally Posted by Stormyweather

So after all this time the summit opti is still the one now? Being that my w/p was leaking at the flange and Im there any way. Im thinking of opti as well. Any incite would be nice thanks. Cause MSD isn't? right?

Recently bought a new Delco and turned out it's a reman. Ran great for about 2k when then the rotor broke apart. I did loctite the screws they did not back out. Had a used msd rotor kicking around that I put in and had zero issues and 5k later. Car regularly saw 6500rpm+.

Still a firm believer in a Delco with a msd cap and rotor kit as the best unit to use.

**Injuneer** · 12-31-2017, 08:28 PM

Originally Posted by Spudnick

I got my MSD opti back again today. Repair sheet says that the optical sensor was replaced with an updated one to correct noise issues with the cap. Also looks like they replaced the cap as the one I sent in had a scratch on it. I won't be putting it on my car though since the Summit opti I put on has been running like a champ. I'll probably keep it as a backup.

I'm curious if anyone received theirs back recently with the new sensor and how its working...

I'm still trying to find out what happened to the unit they tested, repaired and returned to BLUEDEMON95.

Interesting that they seem to have determined the "noise" was coming from the cap. I suggested that way back in post #93. Amazing that after all the effort in alerting them to the problem, sending them the data logs/analysis, and pointing them in the right direction, they have stonewalled everything. Not very professional.

Live and learn.