Hey ive got a 87 supra turbo. I recently installed a rebuilt turbo. The car runs fine at idle and even revving it up. When you are driving it down the road it does ok till you push on the gas about half way and it starts to boost it falls on it face..(dies almost) As soon as you let off it fine. The boost is set at like 7 psi. Not sure what else to check..can someone help???? I also have a greddy bov and it doesnt seem to be blowing off. Sounds almost like compressor surge through the intake.
Supra falls on its face under boost...help
- Thread starter j'smk3t
- Start date
j'smk3t said:
check your timing with a light my car was doing the same thing until today i checked my timing with a lighting light and found that my cps was all out of wack
I have an 87t that just started hitting fuel cut at a few #s boost after running fine for 1-2 months after a turbo replacement. I adjusted the TPS with an ohm meter per the manual and it ran a little better and stopped hitting fuel cut at 3-4 #s boost. But it still is running rough.
Can a CPS knock itself off timing? Mine was running rich it seemed and I was getting a little black smoke out the exhaust but that went away when I calibrated the TPS.
Only mods are K&N cone on the AFM/Intake and a straight 3" exhaust and a CT-26 with Garrett 60-1 internals. I can hear a high-pitch exhaust leak kind of noise when I accelerate. The sound seems to come from behind the right side of the radio which is where the turbo elbow is. It will max the stock boost gauge fine and the car pulls pretty strong at high speeds but at low speeds it's a dog.
I haven't tried setting timing again yet. I already swapped w/ new plugs & wires and replaced the TPS (& calibrated it).
If a turbo wasn't getting any / enough oil, how long would it take to ruin itself?
No codes.
Any ideas?
Can a CPS knock itself off timing? Mine was running rich it seemed and I was getting a little black smoke out the exhaust but that went away when I calibrated the TPS.
Only mods are K&N cone on the AFM/Intake and a straight 3" exhaust and a CT-26 with Garrett 60-1 internals. I can hear a high-pitch exhaust leak kind of noise when I accelerate. The sound seems to come from behind the right side of the radio which is where the turbo elbow is. It will max the stock boost gauge fine and the car pulls pretty strong at high speeds but at low speeds it's a dog.
I haven't tried setting timing again yet. I already swapped w/ new plugs & wires and replaced the TPS (& calibrated it).
If a turbo wasn't getting any / enough oil, how long would it take to ruin itself?
No codes.
Any ideas?
tropical 87t said:
first go check your timing with a timing light, it should be at 10* if it is off as long as your cams are in the right positioning then it is your cps ajust it til it is at 10* if you run out of ajustment then you need to pull the cps out and move it a tooth over.
as far as you turbo goes you dont want to ever run the turbo without oil even a little will wreck the turbo from what i know at idle you turbo is spinning at 3000rpm.
Thanks munkysfly. I know the turbo will die without oil. Of course I had to get custom oil feed and drain lines to adapt this turbo. It doesn't take a coolant line like the stock CT-26. It just has an oil feed line and a drain hose out the bottom. I'm trying to figure out a way to confirm oil is circulating through the turbo with the new lines.
I have a feeling the noise I'm hearing is the new turbo. Is it normal for some turbos to sound like a food processor? There is no sign of metal flake in my motor oil which I thought would be there if the turbo was not getting oil. My oil pressure is fine.
I'll try the timing next.
I have a feeling the noise I'm hearing is the new turbo. Is it normal for some turbos to sound like a food processor? There is no sign of metal flake in my motor oil which I thought would be there if the turbo was not getting oil. My oil pressure is fine.
I'll try the timing next.
j'smk3t said:
So the car was fine before the rebuilt turbo was installed?
I'm kind of wondering if its not Fuel Cut you are having if this is the case then it sounds like you have a boost leak. It can be a real pain to get the boost hose that goes to the turbo back on right. I have seen them go on sideways many times and it seems like there on but there not.
Everything was fine except for the stock turbo leaking and burning oil out the exhaust. That's why I replaced it. After I installed the upgraded CT, the car ran great, boosted great, ran strong. Then, two months later it started running rich it seemed, there was a little black smoke out the exhaust. Also, it started hitting fuel cut at about 3-4 psi and was making rough noises that sounded like an exhaust leak.
I replaced the TPS and calibrated like the TSRM said with my volt/ohm meter. Now it's boosting normally and fuel cut is not happening anymore. It's sluggish when I accelerate from a stop but hauls ass when accelerating in gears 3 and 4.
Does the cars computer normally have difficulty adjusting air/fuel with only exhaust and intake mods? And upgraded CT turbo.
I replaced the TPS and calibrated like the TSRM said with my volt/ohm meter. Now it's boosting normally and fuel cut is not happening anymore. It's sluggish when I accelerate from a stop but hauls ass when accelerating in gears 3 and 4.
Does the cars computer normally have difficulty adjusting air/fuel with only exhaust and intake mods? And upgraded CT turbo.
tropical 87t said:
this might be normal i have never driven a turbo car except my supra and im braking it in so i dont really get to boost. i do however know that it takes alot longer to get boost in the lower gears then the higher because there is more load on the car in higher gears.
Is your intake and exhaust upgraded? Because i know with my stock exhaust and intake, my turbo sounded really bad, like a food processor at 8psi, now that I have my intake cut open, and a 3-inch downpipe, the turbo sounds just as it should.
My exhaust is 3" w/ a 3" dp. The intake is just a K&N Fpik cone. The rest of the intake is stock. Maybe I'm just not used to the sound of the upgraded turbo I have now. But after I first installed the turbo, it wasn't this noisy.
Like you said, like a food processor. It's making that noise under super light acceleration, I'm not stomping on the gas.
Like you said, like a food processor. It's making that noise under super light acceleration, I'm not stomping on the gas.
tropical 87t said:
I dont know too much on turbo sound because this is my first turbo car and i never had a stock airbox on it, but i know that when i first drove my car i was like the resurc.bov is pritty loud why would anyone need a vtabov. then i relized that it was so loud because of my intake. and i can easy hear my turbo spooling even before i hit boost for this same reason.
rumptis said:
Sounds like the problem i am having..The original clamp that was on the IC hose to the turbo was shot so i replaced it and still have the same problem..
I adjusted the timing and it was 50 degrees advanced it ran a little better but it still falls on its face..Could it possibly be the fuel pump??
hey, im 100% sure you have a boost leak. thats the exact same thing that happened to me. you can hear the air leaking out when you boost. also, have a friend follow behind you. when you boost lightly, you car will produce a ton of smoke out the rear, its cause your mixture is so rich.
Do you think it could be the compressor hose??Just purchased the lower hard pipe hopefully that solves the problem..I actually noticed the same sound on the last last turbo. thanks for the info..
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