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Old 10-10-2006, 01:18 AM   #1
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Default My troubleshooting thread!

Since installing my kit I've had a number of issues. I thought that it might be worth while to discuss those all in one place and include the solutions. I often search looking for people that are having similar problems, only to find that they never come back and tell what the resolution to their problem is.

Please add to this thread, but keep it on track.

Original Setup:
Greddy Kit
Starion I/C with Bocsh BOV VTA
MSD 2225 Inline Aux Pump
1.8 injectors
Bipes w/FM O2 Clamp

Current Setup:
Greddy Kit
Starion I/C with Bocsh BOV Recirc.
WAlbro 190HP
310cc Supra Injectors
Emanage (autotune, MAP)
LC-1 Wideband


Symptom: While under boost if I tried to go from WOT to partial throttle the car would buck.
Problem: BOV was leaking under boost.
Resolution: Recirculate BOV back into the intake after MAF but before turbo.


Symptom: After installing Emanage w/autotune the car would bog and fall on its face under any boost.
Problem: There was a mistake in the wiring. There are a number of grounds on the ECU harness, but they don't all go to the same place on the body. When installing the emanage I choose the wrong ground (which was at a different location than the O2 sensor). This caused a small voltage differental, ultimately this made the Emanage think the car was running lean and the autotune dumped in a pile of fuel causing the car to **** itself.
Resolution: Verify locations of grounds and make sure that the Emanage, Autotune, ECU and O2 sensor all use a common ground (the ground junction under the Master Cylinder).


Symptom: Small oil leak a couple of days after the turbo install.
Problem: Fitting for oil feed from the block broke in half.
Resolution: Converted oil feed to banjo fittings and -3an oil line.


Symptom: During an autocross run the car completely lost power and would not start. Had to be pushed back to the pits.
Problem: Connector on the back of the bipes came loose.
Resolution: Duct tape and some cursing.


Symptom: At around 4000rpm in 4th or 5th gear the car would initially go rich then slowly go towards stoich and then power would just cut, very much like hitting the rev limiter.
Problem: Even though I was seeing at least 100psi of fuel pressure under boost the OEM pump could not keep up with flow.
Resolution: I removed the MSD Aux pump and just ran with the OE pump. With the return line clamped I saw about 80psi. Under boost I would see the FP go to 70psi and then drop down to 60psi. I think this was causing my fueling to take a **** even though it looked like I had plenty of FP. I replaced the OEM pump with a Walbro 190HP and the problem has gone away.


Symptom: Was not getting as much boost as when I originally installed the kit and spool was slower than normal. Adjusting the MBC all the way down didn't affect boost, disconnecting the wastegate didn't change anything either.
Problem: Sheared stud on the manifold and had a pretty significant leak before the turbo.
Resolution: Had the manfold drilled out and tapped for 3/8" studs. So far so good. Boost is back and spool is much better. It was pretty difficult to tell initially where the exhaust leak was coming from. I used a 2ft length of vacuum hose stuck in my ear, with the other end I ran it around the manifold and was easily able to exactly where the leak was.


Symptom: After installing my LC-1 WBO2 the car would run like crap after it got hot.
Problem: I was using one of the analog outs to simulate narrowband to the ECU/EMB. I installed the WBO2 sensor in the stock greddy location on the DP, which I beleive caused the sensor to get too hot and give inaccurate readings to the ECU.
Resolution: Had a bung welded into the midpipe and moved the WBO2 to just before the cat, installed the 4 Wire O2 sensor in the stock location on the greddy DP and wired it to the ECU. Only using the WBO2 for monitoring. Seemed to fix the problem.


Symptom: Hesitiation transitioning into boost under WOT. This started as a very abrupt hesitation, similar to the kick down on an automatic transmission. Dealing with this while autocrossing was a treat, cause the car to become unpredictable and buck a lot. I beleive there were multiple causes to this problem.

Problem: Base fuel pressure was too low and was difficult to keep consistant. Sometimes I would see 50psi, sometimes 40psi.
Resolution: Rebuilt the BEGI AFPR. Found the spring which applies pressure to the diaphram used to set base was no longer in position and rolling around inside the AFPR. As a result the screw at the top of the AFPR was not doing anything.

Problem: OEM Fuel pump was marginal and wasn't supplying sufficient flow, even with the Aux pump in place.
Resolution: Removed OEM pump and Aux pump and replaced with Walbro 190HP

Problem: Not really sure why this changed anything for sure. It was been suggested that if the signal from the MAF is noisey that the EMB may have a problem with it. I suspect this was the case.
Resolution: Swapped in an RX7 MAF.

Changing each of these helped the problem, but it wasn't until the RX-7 MAF was installed that the problem completely went away.


While frustrating and a pain in the *** all the difficulty I've had have helped me understand the car better. With out the help of a number of people on this forum I would still be cursing the day I installed the turbo.

Hope this might help anyone that is having trouble. And to give anyone a little comfort in knowing that you aren't the only one having ALL the trouble. God hates me too

I also thought that it might be useful to have a forum section ONLY for troubleshootingissues. Might help people quickly sort through all the problems that people have had. Could also move all the old threads that are trouble as well. But maybe I'm the only one that would find this useful.

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Old 10-10-2006, 01:30 AM   #2
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Excellent thread! I wish more people would make/post a logical list of problem and solution of things they have come across. After just searching "ultimate" in the emanage forum for threads relating to my problem I quickl came across over 5 with my exact problem. Sadly however there was never a solution posted in any of them. In fact the majority of the time a thread that I think will contain what I'm looking for disappoints me in the same way. I'm very thankful for the list you've created.

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Old 10-10-2006, 10:39 AM   #3
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Nice thread Jay.... but can you post which ECU ground you are "sharing" for the EM, AT?

I'm curious to see if it's wired into the right one? The car runs fine, but without a WB, I'm curious to see if I'm running as rich as I think with the 305's. <G>

Sticky thread Mods?

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Old 10-10-2006, 11:10 AM   #4
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If memory serves I used 2B when I should have used 2D, this is on my '93. Both are grounds but they go to different locations on the body. It doesn't take much of a difference in voltage to make a pretty significant difference when you are working between 0-1V.

When it was miswired on my car the effect was anything but subtle! As soon as the pressure switch would click over the car would bog like crazy. Looking at the TPS in my logs it showed I was always below 48%.
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