Zac's 1998 RX7

[ProZac]

Chur . It's all the same stuff though, just what we're all used to we find easier. Thing about electrons is that you can't see em, so you have to have some tools that you trust to tell you what's going where, but it's just a different way of getting the job done .

[ProZac]

Got the loom out last night, while procrastinating about writing this report. I also did the dishes, two loads of laundry, and vacuumed. I'm sure any other students out there can relate.

 

The covering was in a real state, super brittle and cracked, oil soaked and pretty stuffed. The actual loom itself underneath isn't in bad shape though, and will repair up nicely.

 

 

Looks like quite a mess eh? It's not actually that bad, pretty simple as far as modernish looms go really.

 

I also found something...

 

 

Those are the four injector plugs, from right to left being Front Secondary, Front Primary, Rear Primary and Rear Secondary. I've confirmed this by matching the wiring colours, and toning the wires back to the ECU plug. I'm sure that when I pulled them off, the two with tape on them were on secondary injectors. Thus the two without tape were on the primary injectors, meaning the Rear Secondary injector was being fired instead of the Rear Primary, it supplies almost twice as much fuel, so it was never going to run right. It's possible the two with the tape were on the Primary injectors, not the secondaries I'm not 100% sure which way around it was, but they were definitely a pair, this would give the same result, but on the front rotor.

 

 

?

 

I won the auction on a series 7 solenoid block, will grab it this week and try to get it apart without fucking it. Will tone out the rest of the loom too and figure out which solenoid is which .

 

Now I might have to actually continue on with this report. Stink.

[d.p.n.s]

Hay have you checked the plugs on the primary and secondary injectors...they may be swapped over..

Yip I'm that guy.

[thegreatestben]

Fuck it would be amazing if the plugs round the wrong way was the problem.

 

Sorry Brad.

[Beaver]

Why you no fix vacuum lines

[EURON8]

Yup. The tape and conduit they used sure does like to get all brittle and shit.

The series 7 blocks come apart.

I can send you some pics tomorrow if you like?

[ProZac]

So. Much. Yes.

 

I'll pm you my email address. Chur!

[ProZac]

Just a warning about this update, It contains much, much tedium, but also a pretty decent level of winning.

Also, no, I don't work at GHD, it was just a pad I found floating around at Uni.

 

With removing the upper intake manifold, I also removed the vacuum block. Anyone that's had anything to do with the vacuum systems on FD RX7's before is bound to tell you horror stories. They certainly are relatively complicated compared to other vehicles. There is some pretty good information available on how the systems work for a Series 6, as they were released in the US, and the USDM service manuals are easy to find. This generation has what's called the 'rats-nest', which is a rack of three way solenoid valves, all connected to various actuators and sources via individual vacuum tubes and a manifold of metal tubes, see exhibit A:

 

 

Apparently this system, after removal of all emissions related malarkey, can be reduced down to this:

 

 

Wow, that looks a whole heap better. Still not great, but certainly better. I should do that, right? One catch. On the Series 7 and above, the 'rats-nest' rack of solenoids was replaced by a much more aesthetically pleasing integrated plastic manifold design:

 

 

As the Series 7 and up RX7's were never sold in the US, I haven't been able to find any FSM data on this update. In fact, finding ANY info on it whatsoever seems to be pretty tricky. This makes it a bit hard to figure out what to put where to simplify it, or indeed check it's correct in the first place! The series 7 update also included an ECU update to 16bit processors, and a change in header plug design.

 

Now, because I'm an internet weapon (this is not true), I've been browsing Yahoo Japan a bit looking for interesting FD parts and gathering info. I stumbled across these:

 

 

Harnesses for plugging a 16bit ecu into an earlier 8bit car. Iiiiiiiiiiiiiiiinteresting. To my mind, this means that the vacuum systems must be functionally the same (or at least very very similar). Excellent, so hopefully this means that I can relate the available Series 6 data to the Series 7 unit, get money, power and bitches (in that order).

 

I need more info on the integrated vacuum manifold. Luckily, I happen to have one, HUZZAH! EURON8 is a bloody good bugger, and sent me some pics detailing how they come apart, and it really is easy to pop them open.

 

 

There are a couple of valves missing from that photo. That is actually a second hand unit I bought from trademe as it had a broken nipple on the plastic manifold, so was pretty much useless except for parts. With a bit of tubing, and a bit of time, I mapped out where all the passages go, which gave me this:

 

 

And this:

 

 

And this:

 

 

And all of these:

 

 

I was able to match up what each solenoid valve in the block did by looking at what colour plug went to it, and tracing this wire back to the ECU header plug, as the pinout for that (which is an internet resource, not from a FSM, but seems to be holding up reliably) tells you what's up. I was then able to compare the vacuum routing of the corresponding valve on the Series 6 FSM info, and determine if it would work the same in the Series 7 manifold black, and where to hook lines too, etc. A couple of tricky spots though, the Series 6 has a few more valves than the 7, and figuring out what they kept, and what they got rid of took a bit of noodling. The Series 7 has no EGR, so I knew this valve wasn't going to be in the manifold, it turns out they moved the Charge Relief valve, which was mounted external to the 'rats-nest' on the Series 6, into the manifold in the Series 7. Other differences from the USDM Series 6 spec are the lack of a Port Air Bypass Valve and Split Air Bypass Valve. Wicked, more valves to not worry about. I also noticed that the wiring colours from the USDM Series 6 manual match up to the JDM Series 7 I have, as long as you look at it logically and don't take anything verbatim.

 

I was thrown by there only being one output wire from the ECU for two valves, both called 'Turbo Control'. One of these valves is fed pressure, and one is fed vacuum (both from tanks, via check valves, so both conditions can exist at the same time). The valves apply pressure and vacuum to either side of the turbo control actuator diaphragm, giving it more grunt without having to increase it's area. Cool.

 

Two of the valves in the manifold block on my car were stuffed, and these matched up to the error codes the ECU was throwing. Good to know that error reporting system works.

 

So, that's allowed me to map out how the vacuum block works, and where to connect each of the 'E' (External) ports on it too, and hopefully get the system working at some stage in the none too distant future . I'll try and get it up and running as it is, without removing any of the emissions gear, If I strike any issues I'll look at simplifying the system. I might tidy up all the info at some stage, as It could help out anyone else with a mis-behaving series 7 or 8, but that can wait till my car is back together .

[Big Value Buddy]

Prozac=Wizard

[yoeddynz]

Cool. I made a cup of tea and ate some chocolate. I think you should blue tack those pictures on the back of the toilet door so you can scan them when a blokes brain is in the height of concentration (which is why we read on the bog)

[Nominal]

Nice work in getting all that sorted out.

[ProZac]

Got a couple of hours this afternoon, so started reassembly. Got the injectors all cleaned up, new filters and o-rings on and put back into the rails. Gave a few other things a quick clean and removed a bit more stuff (counter-intuitive, I know) to make more room.

 

Figuring out the solenoid block was the majority of the battle for the vacuum system, but I still have to map out where all the steel hard vacuum lines go so I can make use of them correctly and keep it all tidy. Not overly hard, just time consuming.

 

I'm also testing all the sensors and actuators against the factory specs during reassembly. It would suck to get it all back together and then find something that should have been fixed while it was apart. I've gone as far as I can today (all the fuel evap system is tested and plumbed). I loaned my vacuum brake bleeding kit to Dad, so I can't test anything further. I'll be doing some tuning in at uni tonight, so I'll borrow the mighty-vac they have there, as it can apply pressure too, so I'll be able to fully test everything .

 

Bullshit update? Yeah, kinda. Pic of what the engine-bay currently looks like:

 

[ProZac]

Some of what I put up here will just be reference for me, so when it's back together, and has issues, I can look through and hopefully find the cockup .

 

Fuel Vent Plumbing:

 

 

As far as I've gotten tonight with the on-car side of the vacuum plumbing:

 

 

Dinner time now, so an end to the fun for the day.

[yoeddynz]

Shit! good work. At this rate it'll be coming to Hanmer then !

[EURON8]

Id be keen as on a copy of the later model vacuum plumbing of you could please sir. Like you we have the info on series 6 but hard to find anything on the later stuff.

I'm sure you have already but make sure all the check valves are in place and are round the right way. Spent ages trying to fix a non boosting batty following the standard process. Then noticed a missing valve. Boom! All the boosts had come back. (Different problem I know, and I'm sure Brad and Jon had that stuff right anyway)

[puddles]

a guy i know just vents the tank to the ground, on the firewall, where the hard lines finish. i can see you are too thorough for that. I'm led to believe the fuel pressure solenoid is only for hot starts and not necessary in nz conditions, i've got away with it missing for ages now, have checked the tune with wideband. I just plumb the regulator to boost source post throttle. You're going well man keep it up

[f100_dreamin]

Loving this thread man, nothing like some in depth diagnostics to get the brain ticking over

[ProZac]

Wasn't really tired when I got back from uni in the wee hours this morning, so spent some time in the garage. Once again, this post is more for my reference than any actual progress.

 

Air Bypass (Blow Off) and Charge Relief Valves both tested and functioning correctly.

 

 

Vacuum Tank tested and held vacuum fine.

 

 

Pressure Tank tested and held pressure fine.

 

 

Check Valves that goes inline with the Pressure Tank is fucked, will need to source another.

 

 

Airbox to Turbo Intake accordian pipe is fucked, will need to source another.

 

 

Figured out how the Secondary Air Injection system is routed through the manifold.

 

 

Tested the Secondary Air Injection unit and is functioning correctly.

 

 

Tested Deceleration Control Dashpot and is working correctly, however will need to be set once the car can be run to normal operating temp. Cold start system looks like it's bee played with, set to somewhat logical settings, but will need to reset once car can be run and warmed up.

 

 

Tested both Wastegate Control and Turbo Precontrol Actuators, both hold pressure and function correctly.

 

 

Tested Charge Control Actuator and it's functioning correctly.

 

 

Just need to test the Turbo Control Actuator now, but its a pig to get at, will jack car up and get at it tomorrow. Started re-running vacuum lines, but really need to remove the secondary turbo intake pipe to get to a couple of the barbs, will also do that while car car is jacked up.

[ProZac]

Did a bunch of Uni work at home today, so split some time to work on this for an hour or so aswell.

 

Tested the Turbo Control Actuator, on the pressure side, functioned correctly. I tested the vacuum side too, didn't climb under the car and actually observe the valve, but the line did hold vacuum.

 

 

Plumbed up the actuator side of the metal pipe manifold that feeds the Charge Relief system.

 

 

Installed and plumbed in the Charge Relief Valve.

 

 

Updated my vacuum port reference map.

 

 

Will hopefully get a bit more time after dinner to have a further play, can hopefully get the injectors installed, secondary air system back together, Air Bypass Valve (blow off valve) installed and start in on the solenoid block. 

[ajg193]

A super worked 4K with a 'lumpy cam ghe' will solve all your problems and still sound like a rotor - all without any vacuum lines at all