ok PEOPLE lets Diagnose this! My 280zxt

[RUZN]

OK as most know from my dozens of threads lol..

 

I have done the 300zxt Z31 1987 ECU swap into my 280zxt.

For the First say 3 weeks everything was wonderful. Then one morning I started burning extremely Rich. So I checked MAF seems to read fine and operate as Normal as Specs can Say. Then I check TPS found that it switch resistance rather fast so Got another.. Installed that Seems better buuuut still Wiggy. So I swaped out coolant Temp sensors from my other Car Again runs a bit bettter but this is whats its doing.

 

Morning: Gotta get her up to about 1500rpm for a couple seconds or it stumbles.

After about 1 min shes good ideling fine.

 

Go to drive: Leave 10foot driveway and everythigs good go to give her about 25%-30% throttle and I bog down puff black smoke turbo spools and I start going as normal tons of power if I full throttle.

 

Stop Light/Stop Sign: idelling fine, go to go again normal pace and Puffs black smoke unless I gun it or lay off and do 10% throttle for a couple seconds then Jam on it! and She flies away

 

Highway: soon as I get up to speed things are god from the 10% throttle range to 30% from 30% to 60% I get some studdering throttle black puffs of smoke strong fuel smell but agian from 60% to WOT 100% Tons of power no Black smoke.

 

So Highways the best drivability bext gas milage..

Intown is horrible, tons of black smoe studdering responce and fouled spark plugs.

 

Now as I said before.. things were perfect for a couple weeks. I did add a Adjustable FPR and played with that to help it work for a bit then went back to Stock FPR thinking I had a Faulty new one. Same issue if not worse cause I cant meter down fuel PSI.

 

I have gone through tons of testing, Searched the net, tested the O2, checked Wiring, splices I made ect ect...

 

At the moment I cant afford injectors as Im currently taking my 1st and Second years of Automechanics (Accelerated courses) so even my time now to Diagnose is limited and its all i got to get to school soooooo.. I have tried alot of things played with timing ect ect..

 

UNUSUAL THINGS:

 

In town I get a fairly solid 80oC temp so almost dead middle but on Highway I have noticed recently it can drop as low as 55oC to 60oC. I was thinking the Turbo coolant lines where pushing to much Hot fluid at the thermostat (as I swapped a 300zxt turbo in) so I made the inlet line come from the thermostat and the outlet go to the lines that run to the Passenger side of the Head and then go into the Heater core. this did help with the temp as Highway it goes only to about 65oC to 70oc at low points.

 

Now is it possible I have to much power and ran the Duty cycle on the Stock injectors to long at a high rate and maybe fried them?

 

Sparkplugs all black sooty so I couldnt have fried all 6 right.. would be strange overnight. I do drive her hvy but I oil her and run her on 94OCT like 100% of the time.

 

I have tried injector cleaner, oil changes, different tps's, temp sensor at the thermostat, new coolant, better wiring.. so before I throw more at it on limited budget.. HAS ANYONE had these symptoms and did they cure it....

 

I wil try swapping my coils tomorrow but not sure if thats it.. though I guess if the coil has issues it would foul plugs but why at WOT and low RPM dos eit run fine.....

 

Any suggestions or help would be greatly appreciated..

 

thnx again GUYS

 

Again yes I am in Mechanics but still leraning thus each day I try something new I leanred hahaha..

 

Cause I'm sure the Cops dont want me driving like a GRANDMA at 40mkh or the opposite driving liek a Bat outta hell 130mph around town LOL...

 

As I said I had it tuned in great before easily dose 130mph so at a loss and need some other minds cause mines getting fried!!!

[RUZN]

Well.... I cranked up the Boost to about 10psi and the car seems to run good..... So thinking somethings wrong with the turbo fins.. maybe rubbing so they stick causing an overfueling condition? no Idea this is a weird one. Everything else seems to check out.. I had it at stock boost and started having the over fueling issues. Now I crank it and its liek somehow better? odd....

[Evan Purple240zt]

Do you have a leak in the plumbing somewhere? Sounds like a leak

[RUZN]

I checked and recut the vacuum hose to Boost sensor. I think it might have been leaking causing possible the wrong signal to ECU. I noticed this morning on way to my exam a puff of smoke as my Fusible link poofed away lol for IGN. I then noticed my plastic around the coil wires was melted.. It seems a little critter had gotten in there by coil and chewed some wires overtime it melted due to Shorting.. oh JOY. cut wires re connected and everything seems to be normal. Lucky nothing major has shown its ugly head yet. Only reason I noticed coil wires was because I was checking Vacuum line to boost sensor and noticed the wire looked odly brown when it was supposed to be green. (As I used new wires for my ECU swap) CPU seems ok so I'll be crossing my fingers in hopes all is well and fusible link did its job.

 

I guess this whole time it was Arcing off body causing no spark at all cylinders, thus it was hard to find cause I switched coils even and everything thinking it was the coil cause everythig was checking out lol. STUPID CRITTERS!!

 

*Gets out Scoped Pellet Hand Gun*

[Jlensbo]

Wait... you put an Electronic Conto; Unit from a 300ZXt into your 280ZXt... with no modifications? Am I reading this right???

[RUZN]

I changed to MAF/240sx TB/300zxt Turbo/300zxt Turbo ECU/ Maxima 1991 TPS et ect ect.. Found out the New o2 sensor I bought was the craps so its was putting out .01V which is totally low so the ECU just added fuel thinking it was needing fuel. I put my stock o2 Back in and everything is grand..