Summit Racing ignition coils

[MooJohn]

I installed new plugs & coils over the weekend and wanted to share that a complete set of 8 coils was only $180. A search showed that people who have them like them, far more so than the Accel or MSD options, and you can't beat the price. Even AutoZone coils would have been $340.

Part number SUM-850594 at summitracing.com will take you to the right set of coils. They're 50k volts if I recall correctly from other forums.

I paired them with NGK 3951 (aka TR55) copper plugs, another proven favorite in the 4v 4.6 world. Factory gap is .055 but I made it more like .052-053 to allow for future wear.

It's not a bad job in these cars either. I'd say it was an hour or so start to finish. None of the old parts looked particularly bad after 13 years and 87k miles but it was time for new. Some of the original plugs had a .062-.065 gap from wear.

Unfortunately it didn't fix the problem I've been chasing - a shudder at light throttle at highway speeds. That finally threw a code and it looks like I'll be investigating the torque converter solenoid soon. Yay!

 

[MooJohn]

Just bumping this to note that my TCC solenoid does not pass its electrical test. I found gunk (looked like watery trans fluid) inside the electrical plug and I hoped that would be the cause of the problem but nope, it isn't. After thoroughly cleaning the plug I tested the TCC solenoid pin with my ohm meter and found infinite resistance instead of the 13-24 ohms it's supposed to be.

I'm going to have a trusted trans shop replace it for me when I get up the $$ since it's a little more involved than I can do on ramps / jackstands.

 

[velocityboy]

Quick question.

I'm thinking of doing the coil swap you suggest here (right after I replace the massively leaking valve cover gaskets/seals that are filling the plug chambers w/ oil).

Only thing that concerns me is that, judging from the picture on Summit's website, these coils are hard epoxy/plastic all the way down. I can't see how they would fit into the "back" bank of plugs next to the firewall unless they were bendable like the OEM ones.

Is the picture wrong, orrr... how did you manage it?

 

[jrdnhsnbrg]

I have the same thing going on right now in my 2001 conti, P1744 code. Had the dash saying check transmission the other day but it hasn't said it since, still has the same shudder as what you described. I feel it mainly around 1500-2000 rpm, anywhere between 30-75 mph. Do let me know how much the repair costs you.

 

[MooJohn]

The Summit coils are built just like the factory - a 100% identical replacement.

My shudder looks like it's a bad torque converter solenoid. I had a trans flush with no improvement so I decided to check the solenoid's resistance. It's supposed to be 13-24 ohms where I got nothing -- an open circuit.

The solenoid is only $35 but the labor is likely to be expensive. It's easy in theory to reach -- remove the side cover of the trans and the solenoid is held in with one bolt. However, Ford made it so the cover doesn't have room to clear the components! This requires the engine to be supported by a crane while half of the various subframe members that surround the trans are removed for clearance so the cover can actually come off. Great design, huh?

This connector is located directly below the air intake tube. It goes straight down into the trans and is covered by a rubber boot. Measure between pin 3 and ground to see if your solenoid is ok.

 

[jrdnhsnbrg]

Not as bad as on my old car, with the 4.6L engine they had to remove the whole intake manifold to get to the starter solenoid but if you had the 4.9L you'd have to remove the exhaust manifolds. I don't know why Cadillac decided to hide their starters so well in the late 90's

 

[jgscott]

Are the Summit coils a higher voltage. I saw posted 50k. What are the stock Ford ones ? Anyone know ?

 

[jrdnhsnbrg]

No idea, but my dash said check transmission 5 times over the course of probably 50 miles tonight and my service engine soon light came on. Rough shifting and a shudder under low-mid throttle, taking it in to the shop tomorrow.