DriftN7

I have a 88 TII with a s5 turbo and a ported wastegate. i get to 10psi at about 3900rpm's and after that it just wants to keep going so far ive seen 20psi by accident. it just keeps climbing fast. How do I fix this?

boostedfc3s

iTrader: (2)

maybe a stupid question but do you have the vac/boost hose hooked up to the WG actuator and is it going to a good source from the engine ?

DriftN7

yes its hooked up

Craiger

iTrader: (1)

Yeah sounds like the wastegate isn't opening properly or at all!! Usually "boost creep" is only a couple psi in the upper RPM's. If you are useing a manual boost controler try turning it out as far as possible and see if the problem still persists. Some of these are insanely sensitive.

DriftN7

i sold my boost contoller because my mechanic said I didint need it for the stock turbo and that it wouldnt help contol this problem

freemanrx7

the s5 turbo has a nipple on the cold side of the turbo that needs to be capped. I have a TII with an s5 ported wastegate. 5.5 all day long. Sounds like the wastegate isn't opening. The cap I'm talking about is right were the TID meets the turbo.

RETed

It sounds like something is definitely wrong.
That's not boost creep - that's just OUT OF CONTROL boost!

First, eliminate the boost gauge...
What kinda boost gauge are you using?

Second, it sounds like the wastegate vacuum line is damaged (and leaking) and / or the wastegate itself is bad.

Can you disconnect the wastegate actuator rod and wire the wastegate flapper open just to test?


-Ted

DriftN7

im using an auto meter guage, the thing is my mechanic said I should port my waste gate and that worked for one day it would creeop up to 13psi in 3rd and to 11-12psi in the other gears which is fne with me. but the next day back to the same OUTA CONTOL BOOST.

Craiger

iTrader: (1)

So let me know if I have thios right? It was shooting up like this on you, you mech told you to port the w/g and you did, it worked for a day, and then started again.

Sounds to me like the wastegate actuator isn't working properly. Make sure that the wastgate is hooked up to the nipple on the compressor houseing and that the vaccume line isn't cracked or anything. Also, look to see if the rod between the actuator and the gate is jamming on anything, and see if you can manually open the wastegate with your hand. If it is not jammed on anything and you canmanually open the wastgate then the actuator is bad.

DriftN7

alright guys i just tested it and ran it down the street redline through 4th gear. ist and 2nd gear stop at 10psi 3rd stops at 14psi and 4th stops at 20psi. my engine has a mild port with new rotor housings pretty recent rebuild. Ive read i shouldnt push more then 14 psi. should I worry about the 20psi in 4th? if not I plan on getting a to4z anyways next spring.

MaczPayne

iTrader: (5)

STOP BOOSTING IT!!!!!

You're very lucky you're not dealing with a blown engine right now.

If you have a pump or a compressor, apply pressure to the wastegate actuator to check for leaks. If it leaks or doesn't operate, you have a bad actuator. Replace it immediately. I had the exact same problem, but I wasn't ballsy enough to get 20psi!

DriftN7

I have put a compressor to it and it works fine no leaks and also my car last night over heated twice. I dont know why its never happened before. the first time I drove 40miles kinda hard cruizin on the highway at 100. I let it cool for about 2and a half hours then drove home but didnt make it home it over headed again I let it cool for over an hour and it wont start.

demontwig

hm. Maybe the boost spikes to 20psi had somethig to do with it?

Sorry, had my 7 been spiking like that it would have sat in my driveway until that **** got fixed.

pdtaylor18

With that level of bosting i bet now you have cooked the engine,also without some sort of FCD it would have more than likely detonated. if you have not then you are very very lucky. You defo need to find out whats wrong but until then keep that right foot off the gas pedal,just take it easy or you will blow not only your engine but turbo as well. just not worth the risk.

Craiger

iTrader: (1)

Actually a FCD (fuel cut defender) would increase the risk of detonation since if the FCD is not on there then the ECU would fuel cut long before boost hits 20lbs; the FCD prevents the ECU from trying to save the engine in an overboost situation.

Otherwise, I agree it sounds like you might have cooked the engine, that is waaaaay too much boost for the stock turbo and that would also be pushing the limit of boost in a rotary on pump fuel (in NA at least). Mix that with you saying you overheated the engine... that is a recipe for detonation.

I hope were wrong on the status of the engine.