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A couple of months ago i had my local tuner install a microtech into my R34 gt-t as well as a greddy boost controller, bosh in tank fuel pump. I got him to throw boost up to 12 psi as well and had it tuned.

1. My tuner tells me that microtech don't make a harness for the r34 model but tells me he shouldn't have a problem hardwiring it. So i go along and he was able to do most of it but it looks like he's still got the standard ecu wired in for some of the auxillary functions.

Now everytime i get it back from a tune it's running rich and it seems to slowly get worse over time. Is this the two ecu's conflicting or is one of the sensors dodgy (already has a new 02 sensor and all the engine management crap is wired into the microtech). I have apexi turbo timer and looking at the a/f ratio it runs at 10.0 in idle (10 is the lowest it can read) and it never seems to break 12, rarely even gets up to 11 (flat to the floor or just cruising). WTF is going on??

2. Also, now every time my turbo spools up (2-3k rpm) i hear this faint rattling noise. Been for a road tune with my tuner and it doesn't apear to be a tuning problem. Anyone had any similar problems.

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https://www.sau.com.au/forums/topic/147542-rattle-on-spool-up-and-other-issues/
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1. would hate to see how it looks on the wiring loom, having both ecu's

2. dont bother with the apexi pen turbo timer AFR, its using the stock narrowband sensor and its useless

3. it could be pinging/detonation or it could be compressor chipping/chopping

not detonation/pinging. Have changed the fuel maps and timing to see if it is pinging and there was no change so we have already ruled that out. I'm pretty sure it's a mechanical problem that's making the noise. I'll try and keep an ear out to see if it gets worse.

As for the running rich, the apexi wasn't the only indicator. The big give away was drowning people in black exhaust taking off at lights (not necessarily flooring it either). In idle it splutters and the exhaust smells of fuel badly. Another thing in low revs is if I'm cruising and want to accelerate i always get a large jerk out of the car, like it's had a massive misfire. Pretty sure it's just dumping fuel in without the air there (once again, no foot to floor, just touching it on).

I guess what i was really asking is if anyone thought the old ecu could be conflicting with the new one even thought it supposedly only has the auxillary functions hooked up to it.

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