I speak from experience - I made my own harness and I think I did an excellent job labelling, checking, double checking, and documenting everything ... and when it was all said and done the car started, I could rev up to about 3500RPM and then the tach and revs when batshit crazy ... I swapped a used harness in (after I re-wired my link sensors) and everything worked fine.

I think I messed something up with the capacitor located in the ignition / fuel injector subharness ... I think theres a reason that no aftermarket has mass / minimally produced an aftermarket engine harness for this car.

 

did this last night with my engineering friend, so first let me explain that the ignition condenser is wired to the passenger bank with cylinders 1,3,&5 all 3 of those cylinders have spark checked with that method. The drivers side bank has 2 Ampseal16 8pin connectors in between it and the ignition condenser and neither cylinder 2,4or6 will spark. We checked the signal from the ecu with an oscilloscope and it is sending a trigger signal to all of them, we also decided to go ahead and order a new ignition condenser as they are only $8 the one I have is rated at 2.2uf and when we checked it again last night it was reading 1.8uf which is 20% off spec. When I get off work tonight I’ll re-wire the ignition coil and condenser pigtails onto one harness and remove the extra connectors in between

 

so for cranking this is what the oem map looks like for ignition timing


if i under stand you correctly for the lower static compression the ignition event should be moved closer to TDC and look more like this?

 

well its looking like i did something along the same line as that trying to make everything prettier and easier to work on, she might be a fair lady but she's a little rough lol

 

I looked at some older maps and maps I saved from buddies and timing ranges from 5 degrees to 12 degrees in my haltech files and I run 20degrees in my link. The ECT and IAT do influence them a little but nothing significant. If you cannot get the car to start with 10 to 20 degrees timing on a cold engine in normal temps than I would rule-out your tune.

 

cool, I’ll still need to dial it in but it looks like you were right and it is a wiring issue

 

Well I replaced the ignition capacitor and still no go, reworked the coil harness again to make sure everything was clear and still haven’t found any issues there, I’m convinced there is an electrical issue somewhere because I keep blowing the shared ecu/ignition fuse every few cranks. I moved the ignition components over to their own fuse and relay but I didn’t have another fuse for the ecu last night to try again before shutting down for the night, I’ll pickup more fuses on the way home for work, if that fuse keeps blowing it will isolate it to ecu if it’s the ignition then the new fuse will go. I think the next step is to get the oscilloscope and see if the ecu is outputting signal. Worse case scenario ecu is damaged, I’m not sure where to go from there but I’ll try to keep you guys updated as I try things and figure stuff out

 

With coils isolated I’m no longer blowing ecu fuse, at least not in the several tries to start it. still no start, or codes. decided on a whim to run temp 4ga grounding cables to each cylinder head, block, and timing cover just in case it was something stupid like a bad ground but no discernible change

 

Before you assume its the ECU I would really just go find a replacement engine harness and swap that out ... yea, it's gonna cost you $100 to $300 but it could be the culprit.

If you want me to send you my spare harness I am more than happy to box it up and send it out and see if that's the issue. My caveat is that I picked it up from a G35 sedan and the seller claimed it was the same harness ... I didnt want to argue with him and I was getting for a steal.

Regardless ... one step at a time...

 

I’ve been looking for a harness but every thing I find is either REVUP or A/T, 😫 I really don’t think it’s the ecu but I would rather check and be sure than wonder, plus checking signal with the oscilloscope will give me insight as to what the cinnamon toast crunch is going on

 

See post below

 

Never-mind I found a non-REVUP, manual, 06 harness on ebay. Double checked the donor vehicles vin to make sure it was non revup and manual. Should be here next week

 

Glad you found one. Wish I saw this earlier. Have a non-rev, manual harness just sitting here with no use you coulda had.

 

Update time,
the harness I ordered came in, and low and behold it’s for an auto, I checked the vin provided in the description again and still came up manual 😑 I decided to just convert it to manual which turned out to be more work than I thought since there are several wire differences between f1, f2, f3, ecu etc for the automatic trans, the good news is all the pins and connectors use the same pins for the engine, I managed to get her started for about 3 seconds and she ran rough before the ecu fuse blew again, replaced the fuse and she ran rough for about 10 seconds and died. Seams like I’m still only getting spark on the passenger side bank. But she is starting now which is at least a step in the right direction, next few things I’m looking at are fuel pressure, I originally set it at 52 but with the car running I was seeing 55-56 so I’ll drop that back down to 50-52. Then I have the extra grounding wires I made previously that I’m going to put back on and see if that doesn’t do anything. I’m not getting any codes yet so I’m hopeful it’s a grounding issue

 

Adding Additional grounding did not help now getting p0300

 

Ok major issue has finally reared its head, I still have some electrical issue. I melted 3 maybe 4 oem coils literally let the magic smoke out and had the coils expand and bubble 🤦‍♂️

 

adjust your dwell time. I have heard that to much dwell will cause them to burn up

 

would they draw additional current that way? Because the fuse for ignition keeps blowing

 

Never mind checked wrong pin

 

I'm not 100% sure on how it works, but I think the coils are essentially capacitors and they will get hot trying to build up and hold a charge for to long. But on the flip side the longer the dwell the more powerful the spark...have to find the happy medium.

http://dtec.net.au/Ignition%20Coil%2...n%20the%20coil.