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Hey guys, Scott Molitor here, You know the loser who put a rotary engine in a subaru that one time.........Well here we are a few years later and for some reason we got the great idea of purchasing a R32 from one of our customers who fell on hard times. This particular car had a built mazworkz head with a stock bottom end, power fc, 1000cc injectors hks turbskis, and a rod knock. I wont go to hard into details of the build but from a control standpoint we've updated the power fc to a link pnp g4x wire specialties harness and a PRP street trigger kit. Originally we were going to keep the power level low and try and use the stock cas. We spec'd the harness from wire specialties for such connection. Last minute got the great idea of doing the AEM replacement cas disk like some many times back in the day. Took the CAS apart installed the disk re assembled and no dice. Ran a scope and it looked bad so I must have messed up some how. (Been years since I did one but maybe I screwed up). Next best option I thought without tearing the timing back off was a prp street kit. I wired that in unfortunately having to modify the harness which I was trying to avoid in the first place. I really wanted a stock looking RB engine cover w a factory look. When I wired the sensors in (2 Motec, cherry, hall sensors, whatever you want to call them) I didn't use shielded wire. I figured 4+ inches of unshielded wire what harm could that cause. We built out a map with prp's trigger settings, set timing which is rock solid btw. up to 8k rpms no wandering. We thought we were off to the races, so to speak. Unfortunately the car suddenly lost rpm signal and died. First seeing some rpms drop out on the laptop as well as the tach on the dash. Initially we thought we had an issue with the air gap changing as things warmed up so I spaced out the billet prp mount from the timing cover and re set air gaps. No change. Then I re wired w prp's supplied shield wire, thinking ok maybe it is a big deal to have shielded wire for the last 4 inches. Nope, no change. Then we sent the ECU to link to have them bench test it. Tested good. We asked for a loaner just to be sure. No change. I've moved grounds around on the engine, no change. I've heated coil packs up with a heat gun, no change. I've disconnected the can lambda just because, no change. I've flipped the inner hall with the outer hall no change. Air gaps are solid. Supply voltage solid. Wiring solid. I'm at a total loss here, I've talked to Wire specialties, Link, Raw brokerage, other local RB builders and tuners. I'm questioning the PRP Street setup, If your not familiar with it it puts a cam and crank 2 hall sensors off the factory cas spot with a trigger wheel that runs off the exhaust cam. I have the 12 tooth setup. We originally thought we found the issue with the kit being an early version that had steel hardware (they revised the new kits to use TI hardware. Bingo that's IT !!!!!! NO THATS NOT IT HAAA Remember the OP title guys We're in RB hell. The Tooth pattern that the sensors want to see according to Cherry is not how prp machined the disk, call it a space challenge, it. However on the cam home signal there is a little magnet pressed into the stud. ITs the only one on the wheel. I thought what are the chances the mag pole is wrong. Well.... I have no idea if that's the case or how to test. What's the side affect of that being the issue if it was in fact manufactured wrong? would it run at all or for a little while before the ECU freaks out? All I know is when I hold the sensor new the mag it pushes it away, not attract. So is that right or wrong. Prp messages me back every few days weeks ect. That's why this is so frustrating because this car has been sitting ready to break in for months. If this was a customers car we'd be fucked. Recently prp said they have installed the mag in the stud wrong before but gave me no info on what the symptoms would be, just asking what the scope looks like which we've been over, months ago. This Isn't rocket science guys. This was our first prp street trigger, but as far as setting up cars we literally tune 2 sometimes three cars a day banging out link, haltech, emtron, now bosch motorsport cobb ect. What the hell is happening. Recap. Car runs great seems to decay when it warms up. run a scope things look great, After the car has the hiccup re run a scope and it looks like shit. Links remoted in, tried things themselves, there stumped too. Is this trigger kit inferior ? Is the link overly sensitive, Is the trigger kit too busy, everything's packed in too tight of a space and asking for problems ?

Do you have the scope captures from before and after that you can share?

Your post is a pain to read through. If you structure the message and focus on the key elements, this will be helpful.

Stephen I can email logs to you if you like

I can certainly send logs to whom ever. I’ll work on getting a screen capture in the mean time. Its shows a good clean consistent pattern until it doesn't. When it’s not it looks broken up. On both cam and crank. Almost as if the air gaps have changed drastically. What I can’t seem to find out however, is if the hall sensor that prp uses, the cherry, motec unit is supposed to be attracted to the home stud with the magnet or is supposed to feel like its repelling it. Or if it even matters. I would think, like the ferrous metal the wheel is made from, it should be attracted to the stud. Mine certainly does repel the stud as it passes, and prp has said that they have installed the magnets backwards before. I just have no way of knowing what issues will that cause if any.

I've used the AEM disc in stock brand new CAS with Link years ago and it did work, but getting a new CAS became difficult, so many years ago I moved on to using Ross trigger kits with GT101 sensors on SR/RB with Link, Motec.

I've not used the PRP one and can't offer insight on it based on experience, but ultimately getting a trigger scope of when it's working vs. not working would help you narrow things down.

Ill get some screen shots

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