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Technical Questions and Answers - Question it

Fixing what you broke

Eric Hsu
Mar 8, 2013

Got a burning question or simply need some advice with problems you've encountered while wrenching on your current/future projects? Ask our automotive guru Eric Hsu anything-literally, he's going to answer every single question, as long as it's automotive related.

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Transmission Failure

I own a '07 Civic Si sedan with 78K miles on it. Since it started getting really hot this summer, I have noticed that my gears will lock up in higher rpm at around 7,000, and will not allow me to shift easily in pretty much every gear until the rpm is back down to around 5,000 to 5,500. When it is cooler at night, it seems to be a little easier to get into gears. I have done some research and found out that it could be my clutch master cylinder, which does click, pop, and creak a bit, or that I need to replace the manual transmission oil, which I know hasn't been replaced since I bought the car (about 30,000 miles ago). I have also read that all the previous suggestions are just Band-Aids for failing gear synchros, and I must drive like an idiot to even have this problem. Anyway, I was hoping you could shed some light on the issue and give me your thoughts before I go buy stuff I don't need.

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Hugh Thompson, via

As with any problem, it's hard to diagnose via the Internet but it sounds like your transmission problems could be caused from several issues:

  • The transmission fluid is old and broken down and needs to be replaced. The trans fluid is a scheduled maintenance item at 30,000 miles so you should probably change it anyway. Honda's manual transmission fluid is a really thin fluid with additives specifically meant to benefit synchro life. However, switching to a higher quality manual transmission fluid is a good idea, such as Royal Purple Synchromax MTF. Synthetic fluids maintain their viscosity better and do not thin out as much with temperature changes allowing the synchros the lubrication they need to function properly. If your syncros are already worn to crap, there isn't anything anybody can do for you except to rebuild the transmission with new synchros.
  • The master or slave cylinder can also be worn or leaking, causing the clutch to not fully release. This problem will be even more apparent at higher rpm like you are experiencing. Typically slave cylinders fail before masters do, so I would check there first. A quick bleed of the slave cylinder is a good idea to eliminate this possibility first. If you find that bleeding makes the issue go away temporarily and the problem creeps back, then chances are you may have a bad slave or master cylinder. Any clicking, popping, or creaking also tells me the issue is probably at the slave cylinder since that is where the mechanical action is. If there is in fact a TSB, then having a friendly chat with a service writer at your local Honda dealership might be able to get the problem fixed at no charge. It's easier if your car is still under warranty however.
  • There could be an issue with the clutch itself or the fork assembly. Is this the factory clutch? Has it ever been changed? Do you drive like a maniac? Perhaps it isn't releasing all the way because of a broken rivet on the clutch disc or pressure plate. Unfortunately there's no easy way to diagnose this one unless the access window is fairly large. If so, you can take a peek in there with a bright flashlight and see if there are any obvious issues.

Turbocharged Automatic

I own a '01 Honda Accord sedan with an automatic F23A SOHC VTEC engine. Over the summer I purchased a universal T3/T4 T04E turbocharger and all of the necessary hardware that I needed to complete the assembly (i.e. intercooler, wastegate, cast-iron manifold, and more). I contacted a local tuner shop and he said that automatic cars couldn't be turbocharged because automatic transmissions cannot handle the additional power. As a result I put this project on hold. Is it true that the automatic transmission in my Accord cannot handle the additional power from a turbocharger even if I change out the wastegate spring for a 5-psi spring? This was more of a learning project rather than a power gain project.

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After putting the turbocharger project on hold I've thought about swapping out the engine for an automatic H23A Blue Top DOHC VTEC engine, but there seems to be conflicting information about the wiring harness in order to successfully complete the engine swap. Some people have been saying that it's basically plug-and-play in terms of the wiring harness since both engines are OBD-II. I doubt this claim since the engines are different.

ECU: I'm not sure which ECU I need to use. Some engines are sold with the H23A ECU, but other people claim that a certain ECU must be used with a certain modifications.

Motor Mounts: Some people on the forums have said that the existing motor mounts for the F23A can be used, but the driver-side mount must be replaced with a different one. Wouldn't all the mounts be different since the engine is different?

From what I read online it seems like all I would need from a donor car is the H23A engine with the auto transmission, H23A ECU, H23A intake manifold, H23A exhaust manifold, H23A cat converter, injectors/fuel rail, H23A A/C compressor, H23A alternator, H23A distributor, H23A throttle body, H23A torque converter, and custom motor mounts in addition to my F23A wiring harness. Is this all that I need or is there something that I'm missing?

Aaron Yi
Aurora, CO

It isn't impossible to turbocharge an automatic car, but your local tuner shop is generally correct in that the factory transmissions are pretty weak. They automatically break themselves between 100,000 and 140,000 miles anyway. Putting another 100-200 hp through them will simply accelerate that process if they even shift with that additional power. If they don't shift and you keep applying the power, they'll fail in 5,000 miles from the clutch packs wearing out.

As for your swap, you'll need everything from the H23A car as far as parts go. If you want it all to plug in, you'll need the H23A engine harness and ECU as well. Although there is more than likely some minor rewiring due to the length of the harness at the dash and other harnesses because they are from a righthand-drive car. The dash connector and power connections may be slightly different between USDM and JDM so I recommend you find yourself some service manuals before you dive into the swap. If you want to use the F23 harness and ECU, you probably can with some wire extending and shortening due to component location. There may be some connector differences too so you may have to change some of the connectors out as well. Then, of course, you'll have to find a way to reprogram the ECU to handle the fueling demands of the H23. But I recommend you contact the masterminds at Hondata and pick up their S300 ECU to get the H23 dialed in perfectly.

Engine Management System

I have been thinking about ways of tuning my '04 WRX and need some advice. Your magazine and other sites mention COBB's AccessPort, but which engine management system would you recommend: the AccessPort or AEM Series 2 EMS? Would I need an AccessPort even if get an aftermarket EMS?

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Luke Sullivan, PA

That depends on what your ultimate goal is. For a street/race car that doesn't have the need for extensive data logging, the COBB AccessPort is plenty capable of handling almost anything you can throw at a Subaru EJ engine. They have just released speed density software, which allows you to remove the airflow meter and tune the engine on a MAP sensor and charge air temperature sensor. The nice thing about the AccessPort is that most of the factory parameters in place provide tuners with excellent starting and driveability under most conditions. With a stand-alone ECU, you'll have to tune the starting and driveability from absolute scratch. Starting with base maps are fine, but whoever created the base map sure as hell didn't go through four seasons testing like the Subaru calibration engineers did. On the other hand, the AEM EMS provides more data logging capability, which makes it better suited for a race car. There are pros and cons to each platform, but to generalize I'd say COBB AccessPort is better suited for street and track day cars while the AEM EMS for a race car.

Because Race Car Driver

I am 16 years old and interested in becoming a race car driver like Michael Schumacher status, but I have no clue where to start. I live on the East Coast so race and kart tracks are few and far between. Where should I start?

Jordan, via

Becoming a race car driver requires a combination of attributes like dedication, marketability, social skills, luck (being at the right place at the right time), wealth, and, of course, the absolute most important, the innate ability to drive. I think the easiest place to try your skills first will be at the go-kart track. You could hop behind the wheel of any old car and start blasting on country roads like Mario Andretti did when he was 15, but today's society is much different than it was in the '50s. Andy Griffith (Editor's note: Eric showing his age with his '60s TV show example) isn't going to come to the scene of the accident, pull you out of the car and send you home with a lecture. It'll be more like an episode of Cops when they find you. Also it'll be much easier to injure/kill yourself with the performance of modern-day cars compared to Andretti's cars from the '50s. Go-kart tracks are somewhat safer and designed around potential collisions. So go and find yourself a track where you can rent a kart. Even if it's your semi-local K1, you can still hone your driving skills there before moving on to real cars since the same stuff applies to both go-karts and real cars.

Race car drivers are like rock stars in that the road to stardom is sometimes a hard and long one, so you better be prepared to be a broke ass for years to come. Or if you're good looking, get yourself a sugar momma to support your ass while you drive your way to stardom. Now if you don't have the will or passion to go and find yourself a kart track, you're basically screwed. You're going to have to try a whole lot harder to become a legit race car driver than sending me three sentences by email. I'd start first by changing your fundamental attitude because people and sponsors sure as hell aren't going to hand you opportunities from the start.

Homeless Racer

I'm obtaining my racing permit next spring for road racing and began peaking interest into import cars. Unfortunately, I have the budget of a homeless guy. What import car would you choose for road racing? There are so many to choose from, so I thought I would ask the experts before purchasing one.

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Jeremy, MI

Homeless budgets and racing definitely do not mix, no matter what the platform, but if you have to do it, then I'd probably recommend a '92-95 Honda Civic because of its price versus performance advantage. It's cheap to buy, cheap to race, cheap to modify with a gazillion parts off the shelf, cheap to maintain, and it's fairly fast for what it is. I love watching Civics run circles around Porsches on occasion at track days. Granted this is probably because the driver behind the wheel of the Porsche can't drive, but it's still fun to watch.

By Eric Hsu
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