According to the mech the fuel pump rewire is already done by the previous owner in Japan .
Also with the fuel pump relay remove the car starts and you can drive it when its not suppose to do that
So he is going to go through, the circuit relay wiring and fuel wiring tomorrow according to him thats where the short is

 

Manage to find and fix the short in the circuit relay
Did 3 runs 0.9 bar boost no break up had a big smile .
But after every 3 runs the idle will hunt when you look at the boost gauge the needle will bounce between 300 to 500 mmhg for 5 seconds then will idle normal for 20 seconds then will hunt then normal then hunt and will continue that pattern.
Checked tps the GR wire is not holding its values each time we set it and go out for a drive when we stop it hunts like the above
Going to look at its connector and wiring before changing it.
Does anyone know the systems of a bad tps , why i ask apart from the hunting idle it goes like how a FD was intended to

 

Just finished for the night :
Air pump plug the wires was melted and the copper that was exposed was sparking against the pump, explains the burning smell i use to get, repaired that with new wires and connectors
Silicone hose going to the vacuum chamber was pinched and only noticed that when i had the pressure chamber off to get the air pump wiring. Replaced it with a sard silicone pipe .
Idle was still surging on and off check tps, it was still in spec. Started to close idle air adjustment screw and got the idle perfect no surging.
Tomorrow morning is road test will update further if its fixed or is there more bad wiring.

 

Your car really did have a lot of issues. When there are that many things going wrong at once it's impossible to diagnose as you noticed. At least you know where things stand now and can go from there on any future issues.

 

i was going to mention the idle may need to be adjusted but you mentioned the TPS was out of whack so i figured that needed to be addressed first.

 

Over the weekend finish checking all wiring from boot to cabin, all are fine.
Today started with engine harness,
Turbo precontrol and wastegate control solenoid wiring, melted by the connectors.
O2 sensor connector manifold, wiring melted a bit.
Tps wiring melted high way if i didnt remove the tape i would of not noticed it .
Map sensor connector plastic melted around the pins
So im going to go get connectors for map , o2 and turbo precontrol and wastegate
Is there any easier way to check melted/broken/ loose wiring

 

considering it's not normal, and most are buried under the UIM, no. now the real question is, why are they melting?

 

That was due to the alternator over charged (18.2v) 2 months ago. I think i was replacing the sensors , solenoid and normal service the problem started to narrow itself to wiring and it explains why i couldnt pull codes with the led light due to the wires being bad. Atleast i know the problem is in the engine bay itself and nothing to do with mechanical and turbo aspect of the car. If choosed the single turbo route and management i would of solved this a month ago.

 

I need some clarity
I was checking the wiring going to the fuel rail and injectors. Although i had the injectors out i forgot to check the fuel temperature sensor and when i did checked it, i notice the plug is bad and although im going to match the plug , one time i will change the sensor.
I read that the fuel temperature sensor and water temperature sensor are same and can be interchangable, if thats the case and i cannot find a fuel temperature sensor can i purchase the water temperature instead.
An urgent reply will really help , as i will like to get everything on by tomorrow because Friday or Saturday might be Eid and i will want to use the FD when going visiting

 

Hey man that was me. I was going off of recollection of something that happened to me 12 years ago. The sensors are probably not the same but I am not sure. What I tried to get across when you were troubleshooting is that the connector for water temp sensor is interchangeable with another nearby connector. I made this mistake and my car was not running properly. When I realized I had them plugged in wrong it solved the problem...I'm not sure which connector it can interchange with/reaches but was throwing that out there as a possible culprit for you, it probably does not apply in your situation.

Your fuel sensor is probably fine, I havent heard of those going bad, just the fuel pulsation damper. You want to be careful to only use OEM parts when replacing all of these things, I wouldn't dare to use autozone parts on a complicated and sensitive setup as the turbo rotary.

 

I do understand, why i asked because after checking online both sensors look the same . Unfortunately here our Mazda dealership works with chassis number to allocate parts and the FD is not on their system. Reason i asked, after each time i finish off with one part of the harness , be it wires, connectors or both. I get 3 good runs(at operating temp) and then break up , try pulling codes nothing . So i was going through the error codes that could cause breaking up and testing those sensors,checking connectors and wiring, i crossed out the OMP(as i wont see 0.9) . Also today i notice on stock ecu 0.7 break up. Redom is 0.9 no codes on either yet (dent bank so far 1200usd)

 

Maybe you can email ray at malloy mazda that question?

Hmkparts at aol

If you haven't already I think you may need to replace your main engine harness. Since mostly everything else you replaced already and this is a big expensive one to keep you busy. I'm just joking with you.

What did your mechanic find? It was all the fuel pump wiring causing the issue? Now your boost is consistent and you've solved the problem but you're still cleaning up other small items?

 

The mech was stunned as he thought , fueling was the issue. When he first looked at the rats nest, he told me he get rids of that **** and goes single. He said he did all he could and i couldnt afford 700usd(excluding parts if needed) more for his stay.
I forgot to mention when working yesterday, i had to remove 2 of the 5 hks grounding cables as the copper inside had like fungus on it and the wire was stiff like plastic.
Maybe the a new harness is the way to go
Today is going to be a full day and night on the car. Going to check solenoids once again and its wiring as well as fuel wiring and lastly ignition . If its still the same, then the problem might be both ecu are bad.
But what is confusing me the most when the charge control solenoid nipple broke off ,whilst awaiting for the new solenoids i ran the car poor man non seq and it never gave a problem, when i went back to seq i checked everything over 7 times and everything is in order so why is it breaking as the first hit 0.7/0.9. My old man is convince one of the 3 actuators are jammed

 

Problem is only solved when the three trouble free runs i get from putting it back together last forever.
Taking the manifold off , checking repairing and placed on takes about an 1 to 3 depending on what needs to be done.
When the car is started its left to idle and after the fans kick in. I switch it off check tps value all are good.
First run gradrual build
Second run is wot
Third is a mixture of both
The runs are about 20 to 30 mins stop and go
I switch the car off and start it again , soon as i reach 0.7/0.9 backfires, hits a wall, burns rich for 10sec , when im letting go of the pedal or rolling down hill , the neighbourhood is like a war zone.
So its something electrical and when its hot it acts up.
It revs free, no smoke when start(only black smoke when it breaks) up, coolant levels are always fill, vacuum is great , no funny sounds from the engine

 

Buy a new engine harness

You've replaced everything else

 

mazda doesn't sell the wiring connectors separate, you can source some aftermarket but they're rather obscure and from companies don't like to deal with small nickel and dime orders.

 

Sounds like a solenoid problem because when they fail they act up when hot. You have already identified that it is because when you hooked it up non seqential the problem is gone. So find out what solenoids you bypassed going non sequential and swap all of those out. You said you have a friends with a rats nest, I'd grab that.

You certainly arent afraid of putting work in. I would just slow down your effort and think rather than replace everything infront of you without testing it. You'll never be able to diagnose anything when changing 15 things out at once.

So replace the solenoids, if that doesn't solve it replace the harness with a new one. That's probably not a waste of money any way with the electrical overcharge you had.

You can educate me is an actuator the same as a solenoid? Been more than a decade since I messed with this.

 

The actuator was from my old man evo experience, because of the angle it sits, when it rains water gets in from the bonnet vent and goes in , leaving him with a rusted actuator. Was worth a check.
Yes the harness is next on the list, awaiting the wifes approval lol
For these 2 weeks spent approx 7 hours per day on the car . Since both ecus aint giving codes. I downloaded the code sheet and the solenoids that place it in limp mode , i am replacing one at a time checking its wiring till the harness , bolting everything back on going for a spin , problem occurs, strip all out replace the other and so on. Have the blood and burnt scars to prove it lol. Just finish up for tonight, used it for a full 2 hours no problem constant 0.7bar, it even transition lol that feeling of the second(stock ecu was on was to lazy to try the redom) came to a set of lights like a douche i stalled. Started back up 3 good pulls and problem appeared. So tomorrow is the remaining six solenoids that could cause this . Another 8 hours of back aching day lays ahead.
By the way i did grab his FD rats nest, solenoids and intakes lol. And i didnt touch the fuel temp sensor, i aint experiencing stalling and difficult hot start ups.

 

To be honest, i decided if i did not come right with the break up, i was going to go poor man for a month or 2 and concentrate on spending time with the wife and whats life beyond the bonnet of a FD and then tackle it again. But after tonights drive, i am more determine to sort it out once and for all and lucky Eid is on Saturday so it gives me one more day to neglect the family lol

 

Update : due to work, i could not sort the FD, and the weather here got crap with heavy rains and wind. I had to move the FD to a friends garage. The normal symptoms were still there, even though it had rest for a week. I manage to get half an hour of driving before the breaking up occurred. The only difference now was, when it broke up, i ease off the gas and as i throttled the exhaust loss its tone, i couldnt hear the turbines at all, boost gauge was very erratic after 0 bar pressure. I got to my friends place, went other the car whilst idling and found the problem, turbo manifold gasket on exhaust end and lim end had a huge slit . Explains boost break up when the car use to get hot. As i sorted alot of issues and due to the time the car set(engine had enought time to cool down) whilst i worked on it, the engine operated fine between cold to medium hot and when at operating temp the slit was more exposed. So i got the intakes off, air pump , under covers, o2 sensor, heat shields. Now the turbos.
What i need to know:
The air pump i do not need it, but dont want to remove it due to the water pump. Can i block off the the pipe from it to the intake and the pipe behind it that goes pass the y pipe, and leave its plug connected.
Apart from the restrictors in the wastegate and pre control are there any in the turbo oil lines and coolant lines

Thanks will post after the fix

 

Guys my FD is finally fix
It was not changing the gaskets that help . I admit boost is much more steady but breaking up was still there. Funny thing is after installing the turbo and intakes , the FD refuse to start, it swinged and swinged but nothing, after checking relay, fuse , then went to the tank and pump didnt work at all. Got a new borsch pump installed it in, car started went for couple drives boost was 1bar on stock 1.2bar on redom ecu(boost controller will be installed this weekend to keep it at 0.8 and 1 on redom) . Got back to check everything over and started the car again it only refused, fuel pump didnt come on. When i remove the pump, the fuel pump connector, the half thats under the tank cover(blue connector and white connector). The blue connector was brittle and the pins were loose. So i got new male and female connectors and wire , cleaned it up installed the new wires and connectors . Started the car and for the first time in 3 months it performed how Mazda intended it too, switched it off on etc still no problems at all. I manage to keep the car sequential and i learnt alot.
I thank all for their advice and i hope this thread will help others.
The lesson i learnt is , when diagnosing check everything throughly. Just glad to keep the car sequential