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Where is my boost?

2.6K views 23 replies 6 participants last post by  applesauce  
#1 ·
I am loosing boost, I dont know why. I have it set at 8-9 but tonight when I got on it, it peaked at 5. I drove for a while and got on it again same thing 5psi very fustrating. Also to think about it she has been very slugish. Some please help so i can prevent somehing ugly from happening. Help me. JEEVES hook me up
 
#2 ·
Factory Cat? Having a glogged cat will easily choke the life out of your motor. Does the motor seem to run hotter at all? What about your plumbing; have you checked for vacuum leakes or cracked hoses?
 
#4 ·
For raptorracing I have a high flow cat, Thanks for suggestion. Today I went to my friends shop and we looked for leaks, he figured out that the wastegate is stuck, it wont spring back. We put pressure through it but nothing happened. I know nothing about these stock ct-26 and there wastegates. Has anyone been through this before? Today the same thing 5-6psi is all I get. I think there is more than one problem, There is also oil coming from somewhere maybe a turbo oil line. Help, I did not have much time to check out the situation.
 
#5 ·
oil leaking or burning...if burning and you have low boost, you're turbo may be headed south. Check for shaft play. Wastegate failures are pretty rare, but used CT's are pretty cheap, and you might be able to find someone with one on ebay or such.

Bob
 
#6 ·
update

Alright here it is. I pulled the elbow w/ downpipe off checked for shaft play there is none at all. This turbo only has 59k on it. The leak looks to be a mix between oil and power steering fluid. Note a major leak, just drops. The oil is coming from the front crank seal. That is a fix with the rebuild. Im just waiting to get all of the good parts I want. I think she is running ruff because the o2 sensor is bad. My air fuel stays in lean until the car gets going and warms up after 5 minutes or so. Then it will bounce between stoirce and rich. The turbo spools fine just a little late, im shifting when the turbo gets up. Would the o2 sensor make the car overall turbo too run like that?


Also when doing a complete overhaul could someone hook me up with a list of the key parts I need to get? Thanks
 
#7 ·
applesauce said:
I think she is running ruff because the o2 sensor is bad. My air fuel stays in lean until the car gets going and warms up after 5 minutes or so. Then it will bounce between stoirce and rich. The turbo spools fine just a little late, im shifting when the turbo gets up. Would the o2 sensor make the car overall turbo too run like that?


Also when doing a complete overhaul could someone hook me up with a list of the key parts I need to get? Thanks
Cars will not run rough due to O2 sensor failures. They will run full rich because they can't get a reading. I'm guessing your O2 Gauge is actually an LED light show, it's not a wideband. Correct me if I'm wrong. If it isn't a wideband, ignore it. Narrowband gauges are useless, 100% useless. Ok, I lied. They have ONE purpose. They can tell you whether your O2 sensor is working. If it's bouncing back and forth from Rich -> Lean. It's probably fine.

The turbo spools fine just a little late
When is "Late"?
 
#8 · (Edited)
Reply

When im in first gear shifting to second is when the turbo spools. This is something new. It usually spools faster than that. Sometimes the boost wil hit 8-10psi and others maybe even 5-6psi. Do you think i have a leak in my I/C piping? The air/fuel gauge stays in the red(lean) until she gets going or warms up the it flashes slowly red-yellow. Sometimes it will hit green (rich) when i get on it. But it use to hit green when it spooled all the way through my shifts. Like i said the turbo has no shaft play and has 58k on it. Runs like a sensor is bad or there is some hose leak somewhere. Would a dio. computer tell me the basics? Also she runs hot but when i cut it of last time i check the cat but it was not red or anything looked pretty normal, although i did find a 2 inch crack in the down pipe at toward the end. I would not think that would be a problem.
 
#9 ·
Your O2 gauge runs lean until the car warms up because the ECU is programmed to run fuel a little lean after a cold start to help warm the engine up faster. Your sensor and A/F ratio is fine.

How are you regulating boost? Do you have a boost controller or using free mods? There's not much difference between the 6 psi you have now and the 9 psi you used to have. Sometimes weather can cause that much difference. The same boost settings could yield 15psi during a warm day, and end up at 20psi on a cold night.

Are you able to raise boost at all?
When you looked at the turbo, was there oil in the piping?
 
#10 ·
Yes there was oil in the upper I/C pipe, and last time I cleaned the air filter there was oil in the intake pipe. Not alot though, I thought it was blow-by. Yeah your right about the boost at night changing during day, the air is more dense at night and cooler. When it changes from 6psi to 9-10psi is from me starting the car driving for 15 mins. I start with 10psi and after time it falls to 6psi. Im confused thats at night too. To answer the boost control, I have a manual boost control. With it changing all the time I dont know if its me changing it or the car itself acting up. The check engine light is on now. WTF!!!!
 
#12 ·
Well the check engine light came on because there was no coolant in the radiator and the temp gauge peaked out. My fan shroud broke got jammed in my fan and now I have to get a new one. It caused the coolant to come rushing out from the back up of no flow. I could get an flex-a-lite electric one. It looks like someone cracked it before and tried to glue it back. When replacing this fan with electric what do I have to do beside just taking the clutch fan out? When it rains it pours....
 
#13 ·
Well the check engine light came on because there was no coolant in the radiator and the temp gauge peaked out.
This won't cause the MIL (check engine) light to come on.

Pull your codes and tell me what you get.
 
#15 ·
Oil in the piping doesn't mean jack, it's proably the standard amount of blowby from the PCV system.

Leak in the IC piping would cause overly rich condition, low fuel cut, less boost to the manifold.
 
#16 ·
Jeeves I just want to stop and say thanks for your help from you and the other guys. On to the problem, I must have more than one problem. The fuel cut hits way early and like i said my boost to manifold is up and down. So maybe there is a leak that causes the psi to change. Im gonna check the lower one.
 
#17 ·
Hit it for codes today, nothing not one. On the way home I got on it. I hit the fuel cut out at 5-6 psi 3200 rpms 3rd gear. Those symptons that you said about the I/C pipes I have 2 of them, low boost and low fuel cut....
 
#18 ·
That wasn't about IC pipes, it was about a boost leak. I had 3 bolt sized holes in my factory intercooler. You could have a broken hose clamp, a ripped IC pipe or a leaky gasket anywhere between the throttle body and the head.

It really means a lot of investigative work for you in the long run.

Also be sure to check the first IC hose that comes off the turbo. It usually rips and tears and it's tough to get at. So check it especially.
 
#19 ·
update

Come to find out there is a leak right at the hose clamp on the lower I/C pipe, also got a crack in the downpipe right after the cat. Yes it is the stock downpipe. The guy has a high flow cat for the second one though, but that does no good if I got the stock downpipe. I think the cat is clogged or something.


On order:
Lower /hard Pipe $95 from Speedsource
Custom 3"Downpipe w/ no CATS
 
#21 ·
Just as a future reference to find leaks in the intake you can always use some carb cleaner and spray the suspect leaking area to find leaks. its very flammable and after you spray, the leak will suck it up and the engine will race. Very helpful in finding vaccum leaks. Not the best way, but anyone can do it.

Glad you got your problem fixed.
 
#22 ·
TheOtherCarolla said:
Just as a future reference to find leaks in the intake you can always use some carb cleaner and spray the suspect leaking area to find leaks. its very flammable and after you spray, the leak will suck it up and the engine will race. Very helpful in finding vaccum leaks. Not the best way, but anyone can do it.

Glad you got your problem fixed.
You can do the same with water and it won't leave everything mucky.