Malihide

Hey everyone,

Just made the switch from FC to FD and I love it. However I went to change out the (71 degrees celsius.... ugh) old thermostat because the car would cool down a ton when driving, and I took my UIM off due to shearing a bolt on the water pump housing, and I noticed that there are 3 empty hoses. The car is a 1994 from Japan and it's in great running shape, but the second turbo isn't coming online. The car pulls great at low RPMs but anything past 5000 -and it will rev to redline- isn't putting out power and feels like a slipping clutch. The boost gauge shows little to no boost after about 4500, and as a result I can only hit about 80 km/h in 2nd gear.

Anyway, I've been looking over the vacuum diagram, and noticed that one pipe is purposely empty in 5MT cars. This is the one circled in the bottom of my pic, I think.

Are the other two emissions related and therefore empty in the JDM cars, or could they be part of my problem? The hoses are silicone and appear to be in excellent shape.

I'll try to look over the diagram more in the meantime, but I was wondering if anyone knows off the top of their head. Thanks guys!

Malihide

So I believe the middle one is EGR which would make sense to have removed on a JDM car, but the third (top) one is a little hard for me to figure out. My best guess is the double throttle control, but it appears to be unhooked entirely, even from the solenoid down below.

I know the FC used a vacuum system for this as well in North American cars. Do JDM cars not have this, or am I looking at the wrong line on the diagram? It looks like the dark red one in this pic, and the EGR looks like the yellow one.

j9fd3s

iTrader: (3)

the JDM cars do not have EGR, so i think you're looking at the plumbing that would be used for EGR if that car was a US model.

there is a solenoid for the double throttle in the FD, should open the double throttles at something like 65c

newtgomez

So iirc, the top two are emissions related and the bottom one is in fact the automatic pipe. I had a similar problem when I first got my FD and it did like a 5-hit a wall-7 kind of boost pattern.

If you have the time and money and this car is new to you, I would replace all the vacuum lines, check every solenoid (I had to order 3), and get some viton check valves from Daleclark. With everything working properly, the stock ecu should climb through all the RPM with no issue (Assuming it has the stock ecu). It also helps getting rid of the emissions equipment if your area allows it. These cars become easier to work on the less emissions bs you have to mess with.

Malihide

Hey guys,

Thanks for your responses. Upon further inspection, it does look like they are both for EGR (the double throttle control is right next to the top EGR line and is almost the same shape).

All the vacuum lines are intact and supple, and the check valves appear to be as well. They all look like they've been replaced recently. I'll look up how to check the solenoids, but I'll focus on making sure the first turbo is providing at least 8 lbs of boost first.

My car was running very cold to the point that the temperature gauge would go down after driving without idling for a few minutes. It would go down to less than 1/4. Would the richness prevent me from making enough boost, or does the temperature play into the turbo control system?

DaleClark

iTrader: (55)

If the car is not warmed up, it will be all sorts of slow. Get the car running at the proper temperature first before going further. Bad thermostat is usually the culprit.

Dale

SA3R

Don't wanna ruffle anything Dale, but this guy has a JDM car without all the USA warmup stuff and EGR on it, same as my JDM car.

The JDM cars without all the accelerated warmup stuff are definitely NOT slow when cold!! At least mine isn't.

Malihide

Hey guys, appreciate the suggestions

The car doesn't feel slow at all, but it definitely doesn't pull past 5000 rpms. Its faster if I short shift it... How funny is that for an FD?

The thermostat that was in it was rated for 71 degrees Celsius and it actually had the jiggle pin. I bought an OEM thermostat and it is rated for 82 degrees which is quite a difference, isn't it?

Well, it gave me a hypothesis. The car had been running cold and therefore rich for a while, and the catalytic converter is plugged, preventing me from making 8+ psi in the first turbo. The lines look intact and everything, and come to think of it, the exhaust is a little quieter than it should be. Now I have to deal with the predicament of test pipe vs high flow cat, what with having to port the wastegate and tune and this and that.. I think I'm going to see what caused the hypothetical clogging, because it happened to my FC and it was just the matrix that got jammed sideways. Same symptoms, too. I'll be sure to keep the thread updated for future reference for people.

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Ceylon

iTrader: (3)

All three of those pipes are not used on an early manual JDM FD. Nothing is disconnected. If you need any JDM diagrams, let me know and I'll upload them.

Malihide

Please, if you happen to have them. I wasn't able to find any and it can't hurt to double check.

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Ceylon

iTrader: (3)

Malihide

Thanks a ton! That's really helpful.

By the way, this is a bit off topic, but I see you've owned some JDM FDs. Will any power Fc hook in and work with the JDM harness or will I need a JDM unit?

Edit: thanks for editing out the redundancy, goodfella. I was on my phone and it's pretty laggy.

Nevermind the question about the power FC. I was mistaken, and I guess they are actually made FOR the JDM cars specifically.