(SOLVED)

Hello everyone,

Wondering if anyone has any idea on my problem,
(TT01, K04, Chipped, Catless e.t.c.)

THE ACTUAL QUESTIONS ARE AT THE END OF THE POST, SORRY :-)

The problem started with misfires on Cyl 3 under boost. Once above 15psi (Car chipped, cat less, forge dv, lots of other upgrades. I went through the normal set of "repairs" - plugs, MAF and other things. I skipped the Coil packs as they were three months old but tried to swap them - didn't help;

Today i decided to check the wiring harness to coil packs. Wiring was covered with triple layer of electrical tape and had a heat shield ... probably "hello" from the previous owner. I took of electrical tape and the wiring was in a VERY bad shape ... all cracked but no apparent shorting / thing like that. I covered every crack individually and took it to the test drive. Same thing remains.

I came back home to have a cup of tea. When I was out, the car didn't start. I was unable to connect to ECU either. At this point i was almost certain that ECU made a boo boo ...

After thirty minute of mental break, i was back to normal and decided to check the other thing. I found blown fuse - fuse ten (timing / petro). I replaced it with a new. Once i turne d the key, it immideately went out. Then I disconnected everything I could (coil packs, maf, position sensor e.t.c.), replaced the fuse and tried again. This time I was able to connect to ECU (no errors) and both check engine and EPC were on as they supposed to.

I started to connect things back. Finally, I found a piece which caused fuse 10 to go out. It was a last coil pack (Cyl 4 i guess?). I tried to connect a different one and everything worked.

I can't start the car as I don't have a spare coil pack laying around but I am almost certain it will start.

NOW ... the questions is ...
1. DId anyone ever saw coil pack going so bad that it will blew a fuse (in my case #10)?
2. Is it possible to catch a misfire (ACCORDING TO THE CAR) on Cyl 3 while faulty pack was on Cyl 4?
3. What do i do about wiring harness? While I don't think it was a directly related problem ...

 

1. no 2. seems unlikely, but the car only has 2 knock sensors, so one sensor covering cyl 3 and 4. so who knows. 3. good question, my harness is looking kind of abused as well, and im debating what to do about it. sounds like your beinc thorough, if you figure it out update us. new info for the knowledge base

 

Well, installed a new coil pack to Cyl 3, one of the old to Cyl 4 in place of apparently failed one and old ones to Cyl 1 & 2.

Still misfires ... but now computer says Cyl 2 (Used to say Cyl 3); I guess ill be changing all of them now ...

 

well, wire harness replaced (that was boooooring ...), all four coil packs replaced --- no misfires anymore;

Seems like the wiring was a bottom line, damaged insulation contributed to coil packs failure;