Eternal_Gamer

iTrader: (10)

Wassup guys, I'm a new fd owner. I have owned and worked on fc turbos for over 5+ years but finally jumped into the fd world. The car is a 93 touring by the way. Motor has 30k or so on motor and 64k on chassis. Compression reads 120 psi front and 115 psi rear. So engine is good. Well the problem is I have little to no boost from primary turbo. I hear a noise sometimes from 2000 to 4000 when secondary kicks in the noise goes away. Secondary is boosting 6-7 psi. I've tested the solenoids and they are good. Tested the actuators but I couldn't get any to move accept the control actuator. I don't think I'm doing something right because I applied vacuum to known working one and it didn't move. I also tightened all the hoses and lines and checked fr cracks and replaced as necessary. It sounds like my turbos are shot. Well let me know what u guys think. Any advice will be appreciated right now. Don't really have money for a new set of turbos and I hate buying used turbos due to unknown history they may have. So I most likely will save up for 99 spec turbos.

Eternal_Gamer

iTrader: (10)

CorrectioN: I get 2 lbs of boost in the primary

dgeesaman

iTrader: (7)

It's not your turbos. It's a vacuum line, check valve, solenoid, or actuator.

I would start with basics - does the car have vacuum and pressure stored in the tanks after a drive?

Dave

Eternal_Gamer

iTrader: (10)

Yea I did the tests on the vacuum and pressure tanks like the troubleshooting said. They all passed.

IRPerformance

iTrader: (41)

Sounds like a control issue to me or a boost leak. Doubt the turbos are bad.

Eternal_Gamer

iTrader: (10)

I hooked up a smoke machine that we have at the shop and there were no leaks except the air filter which is normally open. So no leaks. Precontrol and wastegate control solenoids passed all tests. The only one I didn't check yet is the turbo control solenoid. I thought the turbos was shot because I hear a noise kind of like whining in low rpms and stops immediately once secondary turbo comes on. Plus I know this block is not the original. Previous owner said the guy he bought it from said the motor went bad from sitting. He could of popped a apex seal and that could of screwed the turbos. Previous owner had rotary performance I think swap in an engine but reused his old turbos. So he said it's been like that ever since. I would think the shop would let it run right before giving it back, but I guess not.

Eternal_Gamer

iTrader: (10)

man ive been so busy working on another guys fc and working at the shop, I havent got time to work on my fd. I plan to start working on it tommorow or Monday, but what I wanted to ask you guys, What are the probable and most likely causes for low boost(2 psi) on primary turbo and medium boost(6-7psi) on secondary turbo? It holds vacuum, has no leaks. Doing searches, it seems people have more problems with the secondary turbo not kicking in. Well, the reason for thinking my turbos is shot is because I hear a noise like whining in low rpms and immediately stops as soon as the secondary turns on. Plus these are original 64k mile turbos. I happen to know a guy with a FD here in Fresno who just bought a new jdm motor from a series 7 or 8, and I was going to switch the wastegates but I figured I might just swap the turbos in since they are an improved design. Let me know what else I should check, if you guys have any ideas of these symptoms.

dgeesaman

iTrader: (7)

There are a lot or reasons for whining sounds, and blown turbos are not usually one of them. If you can get a set of newer turbos then go for it, but I wouldn't expect it to change the boost pattern.

This is probably the best single resource for finding boost issues:
http://www.autosportracetech.com/RX-...leshooting.htm

Eternal_Gamer

iTrader: (10)

I've been using that source and I can't figure it out. I only went through the primary turbo section because I need to get passed that first as it says in there. The only thing left is to swap out the turbos. if it is the wastegates then I might as well switch the turbos since the primary has more shaft play than the n3c1 turbos sitting at my pad.

Eternal_Gamer

iTrader: (10)

Ok, so here is the problem. I get around 2 psi on the primary turbo and 6 psi on the secondary turbo. I've checked for leaks with a smoke machine and didn't find any leaks. I checked all the couplers, pipes, 1" hoses, turbo inlet, to from intercooler and everything is fine. Next I tested the charge control actuator and the rod pulls in and out when the the engine is on and off. I checked the precontrol and wastegate actuators and solenoids and found that the wastegate did not move smoothly. So I went ahead and replaced both actuators with spare parts and solenoids since I broke a nipple. Still 2 psi on primary and 6 psi on secondary. I checked for the pills in the hoses to the wastegate and precontrol actuators and primary turbo and could not find them. So I decided to test by pulling the hoses off the wastegate and precontrol actuators. Primary boost still stayed at 2 psi but secondary turbo boosted up to 8-9psi before I let off fearing of overboost. So now I'm thinking the primary turbo is shot due to it not jumping. Unless there is an exhaust leak where it mates the manifold but i would think it would be pretty audible. If there is an exhaust leak, I'm going to have to pull the turbos out anyways, so before I go through with all that work, I'm open to any suggestions. I got some n3c1 turbos off a 99 spec block my friend got, so I can replace them if I have to. Lmk what u guys think.

Eternal_Gamer

iTrader: (10)

NO one has any input?

GoodfellaFD3S

iTrader: (213)

It might be time to replace all the oem boost control solenoids.

Eternal_Gamer

iTrader: (10)

Well, according to the autosportracetech.com troubleshooting, only the wastegate and precontrol solenoids effect the primary turbo. And I already replaced those. The only other one is the charge control but I tested it and it was fine. Rod pulls in and out.

tt7hvn

iTrader: (5)

have you tested your solenoids after baking them?

dgeesaman did an awesome writeup on putting them in an oven and cooking them up to engine bay temps and then applying the 12v to see if they still actuate.

these solenoids are a pain, sometimes they work and sometimes they don't

Eternal_Gamer

iTrader: (10)

I haven't tried that but I swapped them out for known working solenoids and sane problem. My main problem is the primary turbo not boosting much. Primary at 2psi and secondary at 6psi I tried to bypass it by pulling the hoses with thepills off and primary wouldn't jump boost but the secondary jumped to 8-9 before I let off.

tt7hvn

iTrader: (5)

if they have all been replaced with known working solenoids and you're still not getting proper boost it may be the map sensor has gone bad or your turbos; provided all your vacuum lines are connected correctly

do you have a 3 bar map or the stock one?

Eternal_Gamer

iTrader: (10)

Stock map sensor. I'll double check all the lines again but they are brand new silicone hoses. I'm leaning toward bad turbos or leaking at primary turbo connection to engine. I just don't want to take it all off for nothing. I'll Che k the map sensor to tho. Thanks for the help so far

MB93FD

iTrader: (1)

I would start with check valves, sounds stupid but i had the same problem and i went through all the check and didnt find anything wrong.. so one day i ordered some viton check valves and my peoblem is fixed

Eternal_Gamer

iTrader: (10)

Ok, I think I found my problem. Instead of having a turbo control solenoid which is a 3 way valve, I had a purge control solenoid which is a 2 way valve. I notice vacuum is sent through the 2 way valve constantly and opens more when it gets power. Using the 2 way valve it is sending vacuum to the turbo control actuator and thus opening the door and redirecting the boost to the secondary turbo which was robbing boost to build up for my primary turbo. With the 3 way valve it would stay closed until it gets power. Is my theory right? Tell me what u guys think. Rotary performance did the swap for the prev. Owner, I don't see how they can miss that. I missed it because the autosportrace tech troubleshooting guide didn't list the turbo control system as a primary turbo concern. But after researching and learning how the sequentials work, I tested the turbo control system and found this. So I got a turbo control solenoid from A local guy but found out the coil is bad and wouldn't click over to open the valve. So now I gotta find one to see if this works. Let me know if my diag is right.

dgeesaman

iTrader: (7)

Yes, you cannot switch 2 way valves for 3 way valves. That will mess things up. The one on the ACV is actually a 3 way valve although it looks similar to the 2 way used on the purge control. If you pull off the plastic baffle on the end of a proper turbo control solenoid you'll see the 3rd nipple.

Any 3 way valve is interchangeable, so feel free to dig around used solenoids and select them based on how the perform, not the location they originally operated. Also note the filter baskets can be pulled off and relocated as needed.

Turbo control solenoid in the rack works quite hard, and finding a good one from a set of used solenoids is not easy. I would just buy a brand new one from Mazda for this location unless you have a Mityvac and plenty of solenoids to weed out the couple that are up to the task.

David

Eternal_Gamer

iTrader: (10)

yea, I can't believe rotary performance could miss that. I didn't know at first because I'm new to the fd, but after reading ur writeup and several others, it made sense and I now know how the sequentials work. It's complicated yet fascinating design. I have a mittyvac and all the tools as I'm an ase technician, but the problem is I don't have spare fd parts. I only got fc stuff. I decided to get brand new parts. Found the rack solenoid from fdzero and the one on acv from atkins. A total of $100 . I update when I get the parts next week.

dgeesaman

iTrader: (7)

I think the FC has some of the same solenoids. If they look alike they are alike. Best part is that if they came off of an FC they're much less roasted than anything that's been under the hood of an FD.

Dave

Eternal_Gamer

iTrader: (10)

the turbo control solenoid on the fc is a 2 way valve. The fc solenoids look slightly different but I jus figured I'd get new parts.

Eternal_Gamer

iTrader: (10)

Ok, so I got the solenoids today and threw them in. Put everything back together and start the car up. It seems to idle fine. I take it out for a spin and as soon as I give it about halfway throttle it seems like it wants to boost but it just misses. I can hear the spool up of the turbo now but as soon as boost comes on it misfires and bogs. I'm not sure what's going on now. Maybe I did something wrong. I know I hooked up the coils right, because it seems to idle fine. And acceleration seems ok until I go into boost. The three grounds are grounded together on the manifold. I reconnected the three hoses that were in the way to get the turbo control rack solenoid out. Connected all hoses with check valves to the manifold and the ones on the back including the one to the double throttle control. Map sensor is connected. I'm gonna look at it tommorow but any suggestions will help. Thanks for all the help so far.

dgeesaman

iTrader: (7)

If the MAP is connected then there's nothing obvious.
You could try to check for ECU codes and reset the ECU.

It's not uncommon for FD wiring harnesses to approach the pliability of charcoal, such that working on a car with a roasted harness leads to random electrical problems. If that's the case I'd strongly urge you to 'invest' in a new harness or at least watch the classifieds like a hawk for a good used one. New are $800, good used ones are around $300-600 and they sell fast.