Amoehlau M20 Turbo Build

[Amoehlau]

Haven't had time to post in a while but I've been trying to keep the build moving.

I think after I left off I threw in the electric fan and got that wired up



Then I mounted up the intercooler and started on the plumbing



I finally was able to get the car out of the shed which I had been working in and its now up into the garage. Here's a shot of it in the driveway for the first time in a long time.



I was able to get it up on a lift and build a downpipe. I'm pretty happy with how it turned out.





I also got my wasted spark setup in.



And then this showed up!



So now the real fun starts! Whodwho has been a great help and sent me a base map to get the car running.
I have a horrible repeating back fire while its idling and no matter how much I change timing or fuel it continues. I've gone over every single thing I can imagine and can't find anything obvious that could be causing this (other than the temporarily straight downpipe exhaust). I'm thinking that it may be the fuel pressure regulator not actually regulating and as a result I'm getting too much fuel and don't have much control of fuel delivery. The PO replaced the original with what seems to be a no-name cheap replacement. Could this be my problem? Is it worth it just to put in a nice Bosch replacement anyways?

[Amoehlau]

Well I am still having a misfire issue and occasional backfiring. I have gone over just about every part of the car and I cannot find anything that could be giving me problems. It is always cylinder 2&5 that are misfiring and I have no idea why. If I mix around the three ignition coils it remains the same two cylinders. I have checked all of the wiring up to the coils numerous times and I see nothing wrong, I have swapped the igniter for this coil and it didn't change anything. The only thing I can think is that something is wrong with the ECU and the signal is being broken up somehow. I'm clueless.