I finally got my FIC working after fixing Boomslang's harness wiring and figuring out that AEM was FOS when they told me to use z107 instead of z104. However I still have one problem. Whenever I go WOT past 5000rpm the engine starts to stutter badly and I get a P0335 for crk position sensor failure. I have 2.2K resistors between crk magi+/- and cam magi+/-. AEM suggested that I remove the resistors claiming that the only Scion that ever needed them was the XB1 AT. I think the AEM tech I spoke to is FOS like the other AEM tech who said z107 is best for Scion but what do you guys think? I'm done with asking AEM for advice.

I'm more inclined to lower the resistance from 2.2k to maybe 1.1k or somewhere in between. I'm still trying to discern what resistance you guys are actually running on the crk/cam imputs since no one has yet measured the actual resistance and I'm fairly certain that some have added resistors in parallel to existing resistors. Rustin at Boomslang has assured me that they started adding 2.2k resistors back in 2007 yet I see people still doing the resistor mod in 2009. Pls help... TIA.

 

you did check to make sure the resistors are not burned out? I think i asked you that already so forgive me if i have.

I think i have a spare crank sensor handy if you need one. idk if its any good but it came off an 09 camry so its still fairly new.

the condition sounds exactly like what happens without the resistors, i even got a pretty good data log of it and i can maybe tell you the exact rpm it starts at...give me a sec

 

on this data log i have it (hesitation) starts at exactly 5734rpms and drops the rpms down to a low of 5557, it lasts for about .04 seconds. it did this three times with each one being roughly 1 second apart from each other.

just for grins look through your data log and right where its happening bring up injector duty cycle (doesn't matter which one)...see if it spikes in relation to the hesitation

 

The crk/cam FIC input circuits test at 2.17k ohms R. The crk sensor works perfectly with the FIC bypassed. I can't say exactly where the hesitation begins but it's roughly 5k rpm. Freeze frame data from several events shows the P0335 being set between 5000-6000rpm. My FIC log shows IDC spiking with the high load hesitation event. I can't find anything unusual in my ScanXL logs. If I bypass the FIC, I have no problems.

Thanks for your help. I really appreciate it.

 

i can send you this datalog and you can see for yourself but it really sounds just like what happens when the resistors are not there...I hate to ask but double check the resistors are on the correct wires.

 

Are you sure the xb2 needs them?

 

it would make sense that they are needed...same engine, same sensors, same managment. I think cory did it on his

 

i have one of the first harnesses for the xb2 i dont have any of these problems hmmmm ill give you ca call today fred and chris ill call you back sorry moving into a new house the basement is the dark hole of cell service i will call you guys today

 

Im waiting

 

Everything is wired correctly. I don't know that the XB needs those resistors but Cory has them and Machbox installed them. Cory doesn't have any problems and Machbox said the resistors fixed some similar problems he was having.

What I'm most curious about is whether anyone has added 2.2k resistors to a 2007+ Boomslang harness. If they did, they should have an R value of 1.1K between crk magi+/- and cam magi+/-. If someone with such a harness would test the R between pins 8 & 19 on the 22pin FIC connector and pins 9 & 10 on the 24 pin connector, I'd be very grateful. Just disconnect your FIC, and test with ign off.

 

i just got a call from matchbox he said he is having issues i pointed him to this thread see what he says when he gets in here

 

I've been hardwired in since there was no harness avail when I installed my kit till this day never gotten that code I do have the resistors wired in since day one. I now am code free to include maf code. Its gotta be the harness, send it back for a refund and get the World Racing one since they claim to fixed their issue.

I did get maf code and weird idle and stalling with 107 file so I have been on 104, no problems so far. I gotta get vids and make it to the Dyno, jus have not had the time.

 

same here, iv tuned a few tc's and everyone of em did much better with z104.hex (didnt matter what year either).

 

arron is getting another 02 code i have never seen hope he gets on here and brings it up he has a resistor inline to his 02 and is stuck in open loop

 

resistor is burned out i can almost gurantee it...same poop happend to Kyle (aka HIX)....just ditch the resistor thats on the o2 wire.

 

by the way, welcome to all the xb brethren....lol...i know things are slow in yalls little area

 

I'm just not convinced that the WR harness would be any better. If it isn't, I'm back to square one. Cory's got the same harness with only one difference, the FIC +12V tap. I've already changed that to the exact same circuit Cory's harness taps it from. Essentially we now have the same harness and his works. However I do have a AT and Cory has a MT, fwiw.

IIRC you followed AEM's old instructions and intercepted the crk/cam magi gnd wires? I could try this but AEM now recommends tapping them instead and Boomslang has been tapping them since the first TC harness. This shouldn't matter much but tapping the gnds is better in theory.

BTW, buried in the AEM forum I finally found some useful info about z104, z107 and z110. According to SB (AEM tech), z107 works best with V6's and z110 is for multi-pulse FI systems. That leaves z104 for the rest of us. I'm not too happy with the AEM tech who told me z107 would work better. He wasted a lot of my time with that bad advice.

You may well be right that I should give up on this and buy a harness from WR but I'm stubborn. Besides, WR wouldn't sell their harness w/o their $6500 PnP kit until Boomslang offered one, they offered to tell Boomslang how to fix theirs but only if BS would give them exclusive rights to sell it and WR won't share any info about how they supposedly fixed BS's harness. I'd rather give my business to Boomslang.

BTW, you probably don't need it now but I have a FIC maf voltage log I made with my stock airbox (NA) and it's quite a bit different from the 05-06 TC maf log that AEM has posted on their forum. I've yet to get a MAF code with my map. PM me if you'd like a copy of the map and/or log.

 

Aaron needs to remove that resistor. He shouldn't need one with a WB O2. Mine works fine without any resistor.

 

^^ i just said that...kinda...lol

 

Sorry, I missed that. How would a dead resistor cause the ECU to stay in OL though? At least if it were wired correctly, it would only prevent the FIC from modifying the nernst cell circuit it taps into. I wonder if he installed it into the O2 circuit? That would wreak havoc.

BTW, I love the answers I get when I call AEM.

Me: "so does the fic need a resistor on the WB O2 tap"

AEM: "some do, some don't. Try it and see what happens."

Me: "so is it better to tap the magi gnds or intercept them?"

AEM: "Try it one way and if that doesn't work, try the other way"

Me: "I've installed the prescribed 2.2k resistors on the magi wires but am still getting a P0335 code"

AEM: "Scions don't need those resistors, remove them."