wolek1993

At the beginning I like to admit that I'm from Poland, and my English is not prefect, so I apologize for any mistakes in this text.

I own '86 z31 with VG30ET engine, recently a put new clutch and LSD diff, after that without changing anything in engine I started to have problems.
First of all car lost power. Above 3,5k rpm it was coughing and don't want to accelerate at idle car was shaking . I checked fuel pressure - 2,5 bar, I cleaned MAF with "special fluid" (I don't know how to call it in English), then I remove intake to see what is happening there. It shows that injectors have damaged plugs (there was no things to secure them from remove, I hope you know what I mean). I repaired that and put new spark plugs. Next I installed everything.
When I start up the engine I saw a lot of white smoke coming out from exhaust, I thought that would stop in a minute but it smoking all the time. I disconnected a cooling system from throttle and from intake manifold and it still smoking.
I don't know what to do about it. The worst thing is that it still idle wrong...

rogerz

if all you did was change the clutch and install a new diffy there is no connection whatsoever to the symptoms you describe. White smoke usually means blown head gasket and you are burning coolant. Is white for sure? Blue smoke usually burning lube oil. Did you somehow mess up the exhaust system pulling the tranny? This would affect your turbocharger. if you need new connectors for the fuel injectors you can buy them new on line or parts store. Best ones are go to a junkyard find old volvos and cut them off there. Really quality unit. Need to find two cars tho because volvos are four bangers. Are you sure you didn't disconnect the cooling water to the turbo. it might appear to go to the throttle but no it is for the turbo. If you really revved up the engine checking out the new clutch may have caused head gasket to go. 2.5 bar is a little high for fuel but not enough to cause major problems

wolek1993

I'm not 100% sure that is white, maybe little grayish it isn't blue. I remove spark plugs today and they are black. It appears that i have to rich mixture (I don't know is it right word for fuel and air). I checked the compression it was from 9,1 to 9,8 but the engine was cold. If head gasket went down the compression shouldn't be lower? I didn't revved up the engine because of lost power at the beginning. I didn't want to broke sth down.
The exhaust system is ok, I checked it. A new connectors I will buy tomorrow for 6zł each (about 2$) :P My turbo looks that don't have water cooling. Is T3 turbo have water cooling?

rogerz

the american version did. there are two tubes that go under the throttle body and down to the turbo. i think maybe you lost a bearing in the turbo and are burning lube oil. that would explain the smoke and the fouled plugs. Coolant smoke is really white lube oil is not blue like the sky but definitely has a blue tinge I'd look in the turbo inlet and wiggle things to see if there is any play. Use fingers not a screwdriver. My ancestors were Czech but I was born in US

wolek1993

I know like the oil smoke look like, I have turbo problem in Audi A4, and Subaru Impreza GT, also in Subie I have head gasket blown and I kind know how it looks like. Of course I would like into a turbo to make sure that is ok. I think that can be a fuel issue, but I don't know what would caused this. Damaged lambda would be a reason of very very rich mixture? I read that grey smoke and black spark plugs can be a symptom of wrong air fuel ratio, is it true?
So you have a slavic roots Polish is very similar Czech language.
Pozdrawiam (greetings in polish)

rogerz

yes too rich a mix can cause smoke but usually it is fairly black like when you see a diesel motor rev up. it will make the plugs black. Check to be sure you didn't do something to the O2 sensor when you worked on tranny. if disconnected or broken can cause what you are seeing. you can download the factory service manual from xenonz31.com site or something like that lots of information there. be sure there are no vacuum leaks check the intake piping. if the MAF isn't getting correct air flow thru it then it can't tell how long to open the injectors. check the maf connector for corrosion. I'm thinking it is something simple like some wires disconnected because of the work you did. fuel pressure should vary from about 2.1 to just under 3.0 bar. I was chief engineer on a Diesel ship made in Japan so our gages were in bar otherwise most americans don't know what a bar is. You have some very strange symptoms. I know z31 pretty well owned three of them. present one is an 86T. Don't know any Czech if a kid said something in Czech you got hit alongside the ear by Grandpa and told speak english you American. best advice I can give at this point is get the FSM and study it.

wolek1993

I already have FSM and I'm studying it all the time MAF was cleaned, I'll checked it one more time the connectors.
I don't know how to check the O2 sensor (we call it "sonda lambda") It is connected for sure, but if work properly, I don't know.
Now I'm changing a intake manifold gasket to be sure there are no leaks, intake piping checked twice.
I forgot that in America you use PSI not BAR
The thing that I hadn't mentioned is the car have MBC and boost set at 1 bar (14,5 psi), some changes in ECU was done, but not by me. It worked fine earlier, so I don't thing that's a problem. I'm building it for drifting, so it will be pretty insane car :P

rogerz

1 bar boost is a little high for regular gas. I'm running 10psi on mine. Do you have a boost gage? I took the safety valve off the right side of plenum and just plugged it off. but even if yours is losing boost doesn't explain the smoke. Are you losing coolant? are you losing oil? O2 sensor would affect mix. CHTS might also but not usually to that extent. congratulations you stumped me. Does the engine rev up normally if you are not in gear just sitting on the street? There is a rev limiter on the turbo models (at least US)
Compression test not always a sure thing if head gasket problem. You getting any coolant in the Oil?

wolek1993

The oil is clean, no coolant in it. I can't say if I'm loosing coolant because I spilled quite a lot when I was removing intake manifold. I don't have boost gauge (only the original one) I have safety valve removed too.
I didn't rev up to maximum because I was scared that I brake something, and the smoke would kill the neighbors :P Now the car is standing in garage, I'll drive it on the street only when I'll handle all the problems.
Next plans is to make a new gasket for intake manifold (between this lower and higher part) I can't get this gasket anywhere in Poland... Also I want to change coolant piping to bypass intake manifold and throttle Then put new connectors to injectors. At the end I'll try to find another O2 sensor to check if it will change anything.
What mean CHTS?
Detonation sensor can caused the problem? The wire is broken, but I don't know if I damaged it when I was taking off the manifold now or it was broken before.

rogerz

cylinder head temperature sensor. buried on driver side of engine up front. really hard to see unless you take off the bracket holding the A/C belt idler pulley. Amazon.com

sign up for prime and see what they will ship to Europe for?????

Why did you take off the intake manifold you said all you touched was clutch and diffy. Whenever something goes wrong remember the magic words. "what did I do Last"

doubt it is your det sensor. Easy for you to get VDO gages put in a real boost gage.

wolek1993

I don't need this gasket this is between head and manifold, I need this with 6 holes in it between runners and plenum if I can call it in this way. But it is no problem to cut it from material for gaskets. I already bought some. And shipping from USA or even other country in Europe will take a lot of time.
I want to buy a Depo gages 60mm with warning, it is pretty good and in quite good price and replace a original one.
I take manifold to check injectors and it was good idea because of broken connectors.
At first I had to check what we were talking about earlier, we'll see what happen then