Hi Guys

My FD had its alternator over charged and along with it went the :
REDOM ECU
Tach and speedo
Main Fuse

Long story short, Alternator got repaired and I manage to replace the :
The charge control and turbo control solenoids (as the nipples broke when doing the hose job). Whilst awaiting the Redom ecu to be repaired, I was using a stock ecu and the car ran great until 3 weeks ago, where it started to:
Break up in boost
Stall
Wont start when it is hot
Burn rich and and when it breaks up it will idle crap for a few seconds and then idle normal.

This is what i replaced:
Fuel pump
Fuel filter
Injectors and fuel temperature sensor are good
Plugs, wires and coils
Cleaned the hks ground kit and existing grounds
Water temperature sensor
Oxygen sensor
New belts
TPS still in spec
No boost leaks

The only problem that is still there is the breaking up, its not like the normal limp mode issue. The car wants to go but as I reach 0.3bar its like hitting the wall,back fires, black/brown smoke smells like fuel, will idle like its hunting for a few seconds then idle normal. Like when the map sensor is unplugged.
It is doing on both the stock ecu and Redom ecu
I was told it could be my belts are not tensioned properly
The only thing I have yet to replace is the Map sensor or ecu(as both ecu's cant be bad?) or both

Any advice is urgently requested and appreciated as I am offered a boost pressure sensor for 60USD but is open to any other advise

I do have a good FD its a non smoker(apart from problem mention above) and still holds 550mm/hg vacuum

Its a 1992 Type R 37,000km
Full exhaust system
Blitz twin air intakes
Amemiya LSD
excedy clutch
Custom v mount intercooler and rad setup

 

you should check the error codes before you go changing random parts https://www.rx7club.com/3rd-generati...tarts-1047832/

 

how did the alternator get overcharged? regulator broke and overcharged the system on it's way out?

water temp sensor is what the thread above points to but it looks like youve altready changed that. sure the new one is good?
by the way I think i remember the plug on the water temp sensor being interchangeable with some other plug near it and both could reach each other.
Check to make sure you havent plugged something into the wrong area.

knock sensor could be another sensor to check as well as the air intake temp sensor.

The map sensor could very likely be the culprit, can you test it to see if its in range? if you had a power fc you could see if its reading the right vacuum/boost compared to your gauge. for 60 you may just want to try it.

with the electrical issue you dont know what effects it could have caused. it could be that the overcharge caused a problem in the system and now you fried even the second ecu. try putting another stock ecu in since those are cheaper and if it runs good again for a while you know you have an electrical problem eating ecus. My F150 used to eat map sensors, a couple times a year, never figured out where that electrical problem was coming from. I hope this is not the case for you.

tensioning belts should be an easy variable to get out of the way. just tighten the belts where they are very tight and then you know thats not an issue with slippage.

I'd be weary of boosting or revving high during this trial time.

 

Honestly i do not know how it over charged, i looked at the volt metre and it was 18.2 and poof smoke from cluster.
But all that is repaired and alternater was fixed and the problems was there when the alternator was fitted on with a stock ecu. The problems is no one here has diagnostic for a rx7.
The temperature sensor is working fine .
I am on my way to a friend who has a map sensor and apexi power fc tuned for a twin turbo fd , so ill see what happens

 

all you need is an LED Engine Diagnostics

 

Thanks for the advice.

I will tackle that tomorrow. I am waiting for my friend to finish work so we can test his map sensor and apexi ecu .
Hoping it will end tonight

 

Guys just an update

Ended up purchasing the map sensor as my friend didnt show up.
Notice an improvement car will boost to 0.7 and will break up and the boost gauge needle will move very shaky

The old map sensor will break up at 0.3 and needle use to move steadily

Please help

 

Update

The intake elbow, had a crack so i replaced it with a feed intake elbow and now it builds boost to 0.7 , boost gauge needle moves steady and starts to break up.
Anything else i need to look at maybe fuel pressure ?

 

.7 is around 10 psi

What boost level do you normally run?

What plugs did you put in?

I'd simply try another set of plugs and see how that goes. Possibly the new set was fouled when you were using the bad map sensor.

 

Ngk bur9eq all round

I replaced it last week
Replaced the intake air temperature sensor now its breaking up much earlier, stalled twice
The original boost pattern was 1.2bar on the redom ecu before the alternator blew the ecu .
I am not aiming for 1.2bar i just want to enjoy it like how it was 2 months ago
I replace o2, plugs, wires, coils, map sensor, fuel pump, fuel filter,
Tps in spec, no boost leaks,replace intake elbow, clean grounds, belts, terminals, battery
It has fuel spark and air so what could be wrong
Will a change in ecu work

 

check fuel pressure and injectors

does it throw any codes?

 

The stalling was due to the uim bolts being loose, i must have forgot to tightened them when i replace the air intake sensor. After tightening them it builds boost to 0.7 and breaks/ backfire and will idle really rich.
But when i use the air con it will build steady boost to 0.7 it will break but will idle normal .
Fuel pressure i will check tomorrow as a friend told it can rev free but when driving your fuel pressure could read 0 , does that make sense. Fuel pump fuel filter are new, injectors checked out absolutely fine

 

Put the stock ECU in and pull the codes using the diagnostics. This has been suggested to you three separate times already in this thread but you ignored those people and continued to ask for help.

You want some help but you didn't do the best (most sure fire way to find the problem) solution as was suggested many times.

Simply get the LED and the resistor, follow the instructions posted above, stick it in the diagnostic port and turn the key on. The car will TELL YOU what is wrong in under 10 minutes. You don't need any special diagnostics equipment at all. Did you even click on the diagnostics link provided in this thread and read how easy it is to do yourself? My bet is you never clicked and read the link....

Instead of you replacing random parts and things all over the place, trying apexis... How is that going to help? The apexi has no ability to give you fault codes so that was not going to help you.

Put the stock ECU in. Get codes. 10 mins tops. Then fix problem. The stock ECU will give you fault codes!!

Continuing to ask for help only goes so far. If you don't take the advice to read the codes, you're going to be stuck in a never ending loop of replacing parts, going "Oh that made a tiny bit of difference, next I'll unbolt X and see if that helps... A little... Now I'll unbolt Y.... Didn't help... PLAESES HALP!?"

 

SA3R i did open the link and this morning i tried using both ecus
Redom ecu no flash nothing
Stock ecu just the initial flash when key is on and then nothing.
I double and triple check the instructions and tried both ecus again and same as above
The is after a half an hour drive so engine was at operating
Now is there anything you think i missed

 

Did you check the little diagnostic box in the engine bay.

It's not as simple as turning the key: RX7 FD and Series 5 Error Codes

I just use a paper clip

If you did this and you are not getting codes I'd replace the TPS, knock, resistor and igniter next. If you already replaced those you have basically replaced all the sensors so you have a wiring problem and I'm betting it's a wire relating to injectors or fuel pump. An easy way to get the fuel pump to flow max or bypass the cars controls is simply wiring it straight to the battery and there are lots of threads on this.

 

After going through a few threads, i found out a faulty knock sensor can cause the symptoms my fd is experiencing. I had a look at my knock sensor and notice the black goo oozed a bit out and is exposing the copper thats in the wire
Autozone SA has the MX6 sensor which has the same dimensions as the FD also single wire but connectors are different, will it work or is it frequency/voltage dependant as i tried searching and only sensor replacements i came across on this forum are borsch universal and J&S and read about something like 420/440 cant remember the rest

Thanks again for all the advice

 

Manage to pick up a FD knock sensor from a import engine yard, fit it on and only difference it took away was the hunting idle and stalling, still the 0.7bar break up and running rich.
Got home checked tps and G/R was not giving a reading at all yet last night it was 0.9 to 4.8, the B/G was 0.6 to 4.4
Anyway loosen and got it all close to possible
G/R 1,1 to 5.0
B/G 0.4 to 4.3
No hunting , no running rich accelerate quick but now breaks up at 0.9 bar
Still no codes using led light
Got a rotary mech coming in tomorrow manage to find him 700km away
So will post the possible cause/causes

 

Sounds like this car was a basket case and you are nailing down a lot of issues.

Good luck

 

An expensive basket case

Anyway i got my hands on a spare throttle body with a tps and check uim gasket and get under the car to see if actuator is working as all this is happening on first turbine
Will try it tomorrow
Tonight after mosque, going to run the fuel pump directly and see from there.
Im gonna cross out ignition till that guy reach(he offered a single turbo build but that means i just gave up after coming this far) and concentrate on air and fuel for now

 

Sorry for all the trouble you're going through.

I'd hook up a fuel pressure guage with a long hose and bring it inside the drivers or passengers side while you're boosting and see if it drops. These symptoms happened to me once when I was having fuel pressure drop (inadequate fuel pressure creating a lean condition) there would be no code for this.

You chased down a lot of the critical sensors, ignition and fuel delivery components.

Did you try the ignitor as Fritz mentioned?

I am not familiar enough with the sequential system to say if it could be a turbo solenoid or something to do with the sequential system causing that issue.

Let us know what the mechanic finds. I would also have him put on a wideband airfuel gauge to make sure you are in a safe range with your mods and ecu.
By the way if you are sequential and you were happy with it you should stick to it. I've had a couple different single turbo setups and it's really hard to beat a full bolt on sequential system running high boost like you had.

 

I've never heard of an FD ignitor going bad, ever, in all my years messing with these cars....

You're breaking up at 0.9 bar as measured where, on a gauge? This is with what ecu now? what RPM is is happening at?

 

0.9 bar on the boost gauge
The solenoids and rat nest came of a good working fd(the guy is going single so no need).
Using redom ecu(sent the stock ecu in for hot boarding incase of dry joints, trying to cover all basis)
I will get him to check the fuel pressure and igniter (as thats what he told he will be checking first).
I dont mind paying, its frustrating that you know your car is capable of going well but solve one issue another is still there.
I took 2 weeks off just for this car, to get it right, well will update tomorrow .
Wideband on the redom or stock ecu will it work , i thought its only needed if you have a pfc

 

Oh kay
We busy checking the fuel system electrical,
Notice with the car idling the fuel pump is only getting 10.77 volts
When reving its going to 10.87volts
Then we moved to the front of the car engine still running he remove the fuel pump relay car is still running switch the car off and back on without relay installed(im clueless because it suppose to switch the car off)
Fuel pump relay 11.9volts
Then we moved to circuit relay and it is only getting 9,volts max 10 at 5000rpm
He checked the battery is showing solid 13,9 volts
So the culprit is the circuit relay probably has a short either relay or circuit , his busy running a wire from + terminal to the circuit relay to give it 12 volts constant and we gonna drive and see

What ever is typed on top is how he explained and showed it to me , i aint good at electrical so if anyone can clarify to me whats going on i will really appreciate it

 

The problem is a drop / loss of voltage anywhere from the circuit relay to the fuel pump wiring loom . Earlier the fuel pump was getting 10.8 volts now its getting nothing and circuit relay remains at 9 volts
So tomorrow we are going to go through wires from engine bay to cabin to fuel pump to see where the break in the system is.
Does anybody have the fuel system electrical diagram or have any ideas that i can assist him with, as im hoping this is the problem .

 

normally you won't see battery voltage or even near it at the pump. you can however rewire the relay off the battery directly, use the search function for the DIY threads about it. that will give you battery voltage to the pump and give you a little extra shot of fuel if it really is a fuel delivery issue.