Blob1620 Posted July 10, 2015 Share Posted July 10, 2015 (edited) Hi all,I've been slowly chipping away at my RB-Z build for the last 6-7 months. Ive basically gone from just a motor swap to re doing every system on the car....Anyway, finally got the motor to the point where i could start it. And it runs like garbage. It seems to have the symptoms of highly retarded timing, as, it runs remarkably rich, back fires when throttle is applied, gets super high exhaust temps after barely any time running, etc.It also seems to give no timing advance off idle, as it will bog and basically stall if throttle is applied.I've got a brand new wiring specialties harness on it, which went together nicely, and I have no worries that the wiring is all put together correctly. Every sensor is checked and plugged in fully, and all the basics checked. (grounds and what not)Has anyone else run into such a snag? The one factor remaining is, my o2 sensor isn't installed yet, seems strange to me that it wouldn't at least run correctly in an open loop scenario, not requiring an o2 till its warmed up.Any insights would be appreciated, Thanks folks! Edited July 10, 2015 by Blob1620 Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted July 10, 2015 Share Posted July 10, 2015 Not sure if it's possible even with the factory harness, but is there anywhere in the harness where a connector could be swapped? Usually they design them where it's not possible, when 2 connectors within reach of each other are the same type, but this does happen. Quote Link to comment Share on other sites More sharing options...
Blob1620 Posted July 10, 2015 Author Share Posted July 10, 2015 Not sure if it's possible even with the factory harness, but is there anywhere in the harness where a connector could be swapped? Usually they design them where it's not possible, when 2 connectors within reach of each other are the same type, but this does happen. That was my first thought, but everything is keyed nicely, and doesn't seem to be capable of connecting to an incorrect location. I've been doing some research on timing the engine, and apparently the CAS is not set and forget. Seeing as this engine was a fresh rebuild when I purchased it, perhaps checking base timing is the logical next step. The process seems intricate, what with the screw on the ecu you have to run out to put it in the correct mode to check timing, then rubbing your tummy while tapping your head..... Thanks for your input Chris! Quote Link to comment Share on other sites More sharing options...
Blob1620 Posted July 10, 2015 Author Share Posted July 10, 2015 Well, when I got home i played around with the timing, and over the complete range of adjustment the engine is still running like junk, same simptoms, and very hard starting. It also wont hold an idle now. This is leading me down the path that i have a failed sensor of sorts. Has anyone had a MAF go bad and produce similar symptoms? Quote Link to comment Share on other sites More sharing options...
Chris Duncan Posted July 12, 2015 Share Posted July 12, 2015 (edited) The ECU should have a primitive check engine light. It flashes 2 digit codes, slow flash is the 10's digit, fast flash is the 1's. To read it just jump the check wires and turn the key off then on and count the blinks. Google the number and you will probably find what it corresponds to. Or just find the SM. You can ohm test most of the sensors and you should do this at the ECU that way you are checking the wiring at the same time. Pretty much any sensor can cause this symptom. And it should run decent in open loop. here's a screen grab of one of the SM's Edited July 12, 2015 by Chris Duncan Quote Link to comment Share on other sites More sharing options...
ZT-R Posted July 13, 2015 Share Posted July 13, 2015 will it run enough where you can pull plug wire /disconnect coil one by one? Quote Link to comment Share on other sites More sharing options...
theczechone Posted July 13, 2015 Share Posted July 13, 2015 are all your vacuum lines connected properly? I recently started mine, I'm not running the stock ecu so all issues won't apply, but the car was missing heavily and running like crap, just due to some unplugged manifold nipples. Quote Link to comment Share on other sites More sharing options...
Blob1620 Posted July 13, 2015 Author Share Posted July 13, 2015 I made a rookie mistake guys, totally spaced on plumbing the IAC over to the pre turbo intake piping, so the MAR was reading all the IAC inlet air. Thanks for all the suggestions though! While I wait for the plumbing things i need to do that, I got my exhaust all fabbed up, turned out rather nice. Thanks again for the help folks! Quote Link to comment Share on other sites More sharing options...
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