Undiagnosed problem....please helpppp

[OneJZsidzilla]

Okay, I have a 1990 cressida and just did the 1j swap in with the R154. I'm getting some gray smoke out of the exhaust, at one point got some that a friend regarded as blue, but have deemed that I dont have a blown HG. So, being that the turbos are watercooled, I thought maybe some of the coolant was gettting passed the seals into the exhaust. Thats one problem. The second is that for some reason, at WOT, my boost levels rise extremely fast, and as they approach 8 psi I start to hear popping as if it's leaning out or hitting fuel cut. Originally i was running open DP, but was told I was getting some boost creep and that the turbos were overboosting and that that was being caused by the open dp, however I have since gotten exhaust and it didnt solve it. Then I thought fuel filter, but still nothing. I could use any help at this point. Thanks

 

[Mischief7m]

are you running a stock boost gauge, if so, get an aftermarket one, because the stocker is not accurate or responsive at all.

and when the turbos blow, they smoke blue (could be mistaken as gray) because they are oil cooled as well. if the smoking is at idle, or after coming down from a pull, its turbos.

and its possible also that you are running very rich for some reason, causing a blackish (also could be confused for gray) and causing you to break up under wot. when i first got mine running, it was so rich i couldnt get passed 5,500 rpm.

try to get your hands on a wideband?

also, if it smokes right on startup, its likely your valve stem seals.

edit: nevermind on the boost gauge, its a cressida...so its obv aftermarket haha

 

[OneJZsidzilla]

Ok, you hit the nail on the head with one thing, because it only smokes at idle after a pull. However that only explains the smoke, not the overboost issue. However I was thinking an exhaust leak could be causing it. I'm getting the feeling there is a leak right at the exhaust opening of the turbos. I'm going to check that out and see, but thanks for the advice on the turbos. And if it is leaking some oil passed the seals are the turbos shot?

 

[Mischief7m]

um, not totaled, but on the way out. however, 8lbs is not overboost.

i have never heard of leaking caps in the ecu causing boost cut, but i suppose its possible. if you could, try plugging your ecu into another car, or vise versa. if thats not possible, very carefully open it up, and look for leaky caps.

 

[OneJZsidzilla]

yeah, the only trouble is that it more than likely is not 8psi that i'm hitting. If I have a massive exhaust leak which I believe I have, the boost gauge wouldnt be reading correctly and I could actually be boosting 20psi at WOT