Neo Coilpacks

[TriniGT]

I am getting a missfire on my GTT RB25DET engine. I changed the plugs from the Iridiums I had previously gapped from 1.1mm to 0.8mm. I did not like the fact that I had regapped Iridiums so after having this problem I decided to swap in some 1.1mm BKRE7E-11, left them with the 1.1 gapping as well. Problem I have encountered is the famous bad idle and check light flashing at low rpm and having the TCS and SLIP lights on contstantly. I am going to pull the code today and see what is causing it, the coils look perfect no cracks as I inspected them thoroughly but maybe my eyes are deceiving me. I know the usual cause of a misfire is either coilpacks, gapping or in some cases timing. The car worked fine and has never been touched but I always had a slight miss ever since I got the car but in the last week I am getting a break up when in boost and around 5000-6000rpm. My question is are all Neo coilpacks the same, I don't want to run and buy Splitfires as I am removing the engine in a matter of months and I would prefer to get proper working replacements. I am wondering if I can get a set from an N/A RB20DE Neo or RB25DE Neo or will I have to get from an RB25DET Neo setup, does anyone know offhand?

[Hanaldo]

RB25DE Neo and RB25DET Neo coilpacks are exactly the same, I'm not sure about the RB20DE Neo.

[TriniGT]

Thanks will try to get my hands on some.

[V28VX37]

RB25DE Neo and RB25DET Neo coilpacks are exactly the same

Second that, in fact I've got a mix of these in my car now.

TriniGT if you have access to RB20DE Neo check if the coils have HANSHIN MCP-1440 written on them and look like the photo below. If yes they're exactly the same as RB25DE/T Neo coil packs.

I never had any visible damage to my coil packs, however some of the replacement ones I got (2nd hand OEM) were busted when I tested them for correct resistance.

Also have a read through my misfire thread here, it may give you some pointers. Mine is still getting a random stutter on idle, I am planning on re-checking vacuum hoses and cleaning the AAC next.

[TriniGT]

For a neo coilpack what should the resistance be, I am gettign it ranging from 1.5-1.7ohms. Also the coilpacks I got as a spare are MCP-1340 not MCP-1440 like my original setup, would that make a difference?

[TriniGT]

Also I checked the resistance on the primary side of my GTT coilpacks and I have found the culprit. Here are my readings,

Coilpack 1 - 1.686

Coilpack 2 - 1.683

Coilpack 3 - 1.546

Coilpack 4 -

Coilpack 5 - 1.581

Coilpack 6 - 1.671

My Part Number for these coils are MCP-1440 as stated earlier. I got a set off a Neo but not sure if it was an RB20 or 25 as they were off in a box, the part number is MCP-1340. Does anyone know if I can use them? Here is the primary side resistanc eon the five I got,

Coilpack 2 - 1.440

Coilpack 3 - 1.385

Coilpack 4 - 1.423

Coilpack 5 - 1.424

Coilpack 6 - 1.556

Now my next question is is the lower the resistance the better and the higher the resistance? Wondering if I can put it these five and the lowest resistance one from my bunch to make a set? Your thought?

[KiwiRS4T]

I have three different part numbers although I don't have the actual coils to see if they are in fact different:

ALL R34 neo

RB20DE 22433-AA000

RB25DE 22433-AA100

RB25DET 22433-AA101

Measuring resistance is not enough. You need to examine the coils and the surrounding areas to look for shorting or drive at night with tne coil cover and bonnet off (or may be able to see just be loading it up while parked). There are numerous threads on insulating the coils or just reducing the plug gap to .8mm.

[TriniGT]

I don't see the need to regap the plugs, once you have proper spark it should be fine at stock boost. Any way, I got a replacement coilpack and swapped number four and refitted my setup, rechecked timing and started the car. CEL has gone so far but the TCS and SLIP lights are still there. Ran an ECU diagnostic and came up with 17 only this time so the coilpack so far has cured two symptoms. I decided to erase fault codes and start again, so far no codes are appearing, no TCS, SLIP or CEL light. My idle is a little lumpy at times but I am yet to drive her. Maybe with some driving it will clear up. I have since found some other stuff to do to her in the mean time before putting her back on the road; leaking upper rad hose and thrashed steering rack rubbers. Does it ever end.