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Discussion Starter · #1 ·
Okay, it looks like a slightly long and involved post....but it's a very easy read, so Cliff's Notes aren't required here ;)


My car is a 94tt 6spd and only has a manual boost controller and exhaust. The boost controller has been on the car for about 5yrs or more......and set to hit 1.2 or slightly higher (hits another 1/2 bar in cool dry air).

Okay, so I needed new plugs a few months ago and put in the 6097s. Worked beautifully and the Greddy gauge continued to read the same ol 1.2ish bar and pulled good once I hit 4200 rpms.

So then I needed another plug change, and I decided to try the 3330s for comparison right after the 6097s ran 3K miles or so.
Immediately after the 3330s went in, the car felt like ass and would NOT boost past 1.0ish bar for anything. The motor came to a hault at that boost level. So of course I'm blaming the 3330s, right?

I go to the store about 100-200 miles later to swap back to a new set of 6097s, expecting the car to boost right up to 1.2 again. Well, the car feels EXACTLY the way it did with the 3330s in it and continued to only boost 1.0 bar <----and that's an accomplishment.

This has all occured in the past 3 months or so with no major change in weather.
The car has 70K miles on the stock turbos. No other symptoms or scenarios can be added to this story. So, I'm at a loss.
However, the manual boost controller has been spewing a minor oil leak for about a year now if that indicates anything.

Thanks for any insight....I'm clueless at this point except to throw in new coil packs, which I dont mind doing. I just want to CURE the problem, not MASK it ;)

Sean
 

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Highway Demon
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i'm in no way fully experienced enough to give the most valid response to this but it sounds like your turbos are on there way out perhaps.. finding oil in the mbc is a very bad sign.. i know that for sure..

Brian
 

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Discussion Starter · #3 ·
thansk for the response Brian. I do need to check out some new MBCs.

Anybody else?
 

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Alpine Hardtopper
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I have a few ideas.

I didn't notice anything mentioned about the coil pack connectors. Those tend to degrade and crack over time. Could be that during the plug swap to the 3330 a few connectors gave out? Seems to be a common problem with our cars.

Did you notice the gap on the 3330's? If they were significantly larger then the coils would be working a lot harder...could have caused them to fail a little earlier than they may have. You can try to check the resistance on them before replacing.

The oil in the MBC isn't the fault of the MBC at all. It's likely oil from the turbos getting in to the MBC. That's a little more serious of a problem. Pull a few hoses on the IC piping (just after turbos and just before throttle body) and check for oil in them.
 

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Discussion Starter · #5 ·
cord4530 said:
I have a few ideas.

I didn't notice anything mentioned about the coil pack connectors. Those tend to degrade and crack over time. Could be that during the plug swap to the 3330 a few connectors gave out? Seems to be a common problem with our cars.

Did you notice the gap on the 3330's? If they were significantly larger then the coils would be working a lot harder...could have caused them to fail a little earlier than they may have. You can try to check the resistance on them before replacing.

The oil in the MBC isn't the fault of the MBC at all. It's likely oil from the turbos getting in to the MBC. That's a little more serious of a problem. Pull a few hoses on the IC piping (just after turbos and just before throttle body) and check for oil in them.

My coil pack clips are all fine. I replaced them a few months ago with the 6097 install. So I know those are all tight and good.

I left the gap alone on the 3330s...I checked them for consistancy upon installation, and did not adjust the gap at all. I think they come at a 32 gap or so(?)
Although when I put the 2nd (most recent) set of 6097s in, I gapped them down a little to 28 since I'm blowing 17ish lbs at them.

I've always sucked with ohm meters and shit, and since my coil packs are original I don't mind springing for new ones. But I guess they should be checked regardless. I just dont know how to check them myself just yet.

That does concern me about the leaky MBC. You're saying that this is a direct indication to near turbo failure? Exactly which part of which turbo is failing - as this being a red flag???

Thanks for the help so far!

sean
 

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Just a quick note, failed turbos generally don't make a car run like ass. Just lack power. Are you still running cats? If so, have you used race gas? Maybe a symptom of clogged cats. Any check engine lights?
 

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Discussion Starter · #7 ·
Rotarytoy said:
Just a quick note, failed turbos generally don't make a car run like ass. Just lack power. Are you still running cats? If so, have you used race gas? Maybe a symptom of clogged cats. Any check engine lights?

Naw, cats were ditched long ago and the car has never seen race gas. Also, zero check engine lights.

That's what's so frustrating....the car is so basic in mods and just a simple daily driver, yet a sudden problem like this is so mysterious to me.
Is it really that mysterious to all of SF too?? :D :(

Continued thanks and appreciation to any insight!
 

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blkturbo! said:
My coil pack clips are all fine. I replaced them a few months ago with the 6097 install. So I know those are all tight and good.

I left the gap alone on the 3330s...I checked them for consistancy upon installation, and did not adjust the gap at all. I think they come at a 32 gap or so(?)
Although when I put the 2nd (most recent) set of 6097s in, I gapped them down a little to 28 since I'm blowing 17ish lbs at them.

I've always sucked with ohm meters and shit, and since my coil packs are original I don't mind springing for new ones. But I guess they should be checked regardless. I just dont know how to check them myself just yet.

That does concern me about the leaky MBC. You're saying that this is a direct indication to near turbo failure? Exactly which part of which turbo is failing - as this being a red flag???

Thanks for the help so far!

sean
Hey Sean,

Plug gap doesn't seem excessive at all. Not enough to make the coils give out instantly anyway. If you have a FSM, I believe it details the resistance values you should see with an ohm meter. If not I could probably look it up for you in my books (for a 1994).

Rotarytoy is correct about the turbos. They usually make boost just fine right up until when they die. No likely that they're the cause of the boost problem anyway. But the oil still concerns me. Just not knowing where it's coming from. If it is coming from the turbos, it's usually the shaft seal on the compressor side. Having oil leaking in to the intake will usually cause a lot of smoke out the exhaust though (which you didn't mention at all). Anyway, something you'll want to do some detective work on to see where there is oil in the system. That will help diagnose where it's coming from.

Another thing I thought about today was the crankcase vent hoses. Since you already did the coil pack connectors, I'm guessing you're well familiar with replacing those hoses as well. But if one of them was cracked slightly....I suppose it could be venting a lot of metered air and causing the mixture to be excessively rich. Just another thing to check I guess.

Wish I could help more on the troubleshooting. Let me know if you need the coil test information.
 

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Discussion Starter · #9 ·
Actually, I do have the service manuals. I just haven't explored them yet for this since I've been at a loss as to where/how to track the problem (starting point).
I'll see if I can figure out what all is said about checking the coil packs (the how-to).

No, I didn't mention oil out the tailpipe, BUT.....over the past month or so, I have noticed a puff of distinctively blue smoke out the pipe as I leave off idle during normal driving.
As I leave off idle at certain times of the day (so that it's visible), I notice it puffs a blue cloud. And I found it on my own by actually catching it in the side view mirror in my peripheral vision! I just never thought to make the connection between the blue cloud and the hault at 1.0ish bar.
Basically, this boost issue has had me concentrating on electrical (plugs, coils) since it just so happened to begin RIGHT AT the plug change to 3330s.

The boost issue was sudden and very recent....and the oil at the MBC has been going on for several months that I can recall - if that seperates the two issues at all.

I will/should double check the 2 crank hoses. Although very new (few months old), I suppose I could have knicked one with the pliers when removing while warm/soft. I even have a brand new set of them sitting right here, along with a few coil pack clips :)

I'll begin my "homework" tomorrow now that I have some ideas to begin with.

Continued thanks as always!
sean


cord4530 said:
Hey Sean,

Plug gap doesn't seem excessive at all. Not enough to make the coils give out instantly anyway. If you have a FSM, I believe it details the resistance values you should see with an ohm meter. If not I could probably look it up for you in my books (for a 1994).

Rotarytoy is correct about the turbos. They usually make boost just fine right up until when they die. No likely that they're the cause of the boost problem anyway. But the oil still concerns me. Just not knowing where it's coming from. If it is coming from the turbos, it's usually the shaft seal on the compressor side. Having oil leaking in to the intake will usually cause a lot of smoke out the exhaust though (which you didn't mention at all). Anyway, something you'll want to do some detective work on to see where there is oil in the system. That will help diagnose where it's coming from.

Another thing I thought about today was the crankcase vent hoses. Since you already did the coil pack connectors, I'm guessing you're well familiar with replacing those hoses as well. But if one of them was cracked slightly....I suppose it could be venting a lot of metered air and causing the mixture to be excessively rich. Just another thing to check I guess.

Wish I could help more on the troubleshooting. Let me know if you need the coil test information.
 

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Alpine Hardtopper
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Sounds like a good plan.

You're dead right about the oil not being the likely cause of the boost problem. I don't think the two are likely related. Just something to track down once the boost problem is fixed.

I've just been trying to think of what things could have been bumped/disturbed when doing the plug change. Aside from the coil connectors and vent hoses, there's not a lot in the way during a plug change. Hopefully there's a huge rip in one of those hoses <grin>. Or you find that 2-3 of the coils are way out of spec.

Good luck. Let us know if you have any questions on the coil test.
 

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Discussion Starter · #11 ·
Well, Im back from my Vegas vacation....and back to the reality of my car running strange.

I checked the vent hoses today and they're fine. Dont even have that much mileage on them to begin with.

Meanwhile, my car is blowing a thick blue cloud each time I leave off idle (as I mentioned) :( It's very obvious and I'm dying to know the connection between the blue smoke and boost symptom.
I have yet to do a coil pack test yet. Working on that next as I get the chance with my service manual.

I'd like topull a coild pack wire one-by-one while the engine idles.....but I have a fear of electricity. Last time I did a test like this was with my carbuerated mustang (easier?).

Sean
 
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the blue smoke is your valve seals going out they shouldnt have an affect on your ignition system but they will cause your plugs to foul sooner than later. check all your wiring and coils and the igntion and check all the resistance. you might need new coils wiring repairs.
 

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The smoke sounds like a common VSS problem (maybe you werent noticing it before?) I do not think anyone has made any mention of what boost cut device you are using, could something have came up with that at around the time you installed the 3330's causing a coincidence and you blaming the plugs? Also, you are running sequential right? Could it be possible something arose with the sequential system?
 

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Discussion Starter · #14 ·
Thanks for the PM Honda....I'll get to it when I'm off of work,.

Meanwhile, Im using a BCC since many moons ago :D It's not a "cut' device that Im feeling though....or at least Im pretty sure it's not based on the way it doesnt feel like a boost cut sensation.

Th blue smoke has only gotten obvious and noticeable just recently (within a couple of months at most I think).

Thanks everyone. I'll report back as I dig deeper.
sean
 

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OG
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Sean -
One thing to check (this hapened to me) is the polarity of the coil pack connectors. If the wires are cross, the car may not run well. Ohmmeters are no good to check coilpacks, because the impedance is too small to be properly read by the ohmmeters. Te only way to tell that I know of is to check with a set of coilpacks you know to be good - you know where to find those, right? ;)

THe smoke at startup might be turbo seals as well.

Cheers
Rich B.
 

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Sean,

I have a few questions, I read most of the post but I'm alittle wasted and figured I'd check. Your on stock twins in TTC or sequential? I had the same type of problem before when my second turbo wasn't coming online and that was due to a vsv. Did you try to pull the hose off the mbc to see if it would boost higher?

Mike
 

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Yea seanski, i'm putting my money on a vsv. I think you are still in seq. throw that bitch in ttc tommorow and see what you've got. oh and give me a call later, fucker :eatme:
 

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Discussion Starter · #18 · (Edited)
Hey Rich! The blue smoke isn't upon start-up only....it's off idle, every time. If that makes any difference to ya.

Hi Mike.....I'm in sequential...no TTC. I sure hope it's not any VSV since I'd hate to have to dig into all that mysterious crap, lol.
Plus, I'm getting the 2nd turbo to come online, it just wont make full boost to 17ish lbs. It (2nd turbo) comes on but then runs flat above say 5k-5500ish rpm.

Brenden, yeah I need to call you again (so you can answer the phone, haha). I'll try tonight or tomorrow when I get a few minutes.

Further updates when I can stop long enough to work on my own shit for a change!! lol

(Edit - OT): Congrats on the big news Mike, and save some of those drinks for when I get up there :D
 

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Sorry bout that earlier post Sean, but the news is driving me to drink. Goodluck getting Brenda to call you back, he's on with his woman all the time now :gaysex:

So you can still feel the 2nd turbo coming on?, hmmm. I imagine you've looked for a boost leak already? I think it's time to go single my friend. I had trouble with my 2nd turbo coming on and I believe it's the car telling you it's wanting more power :sadance: so I just had to :) Really though you should try TTC and see how it goes then. Besides running in TTC will set you up for the lag when you decide to go single!
 

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blkturbo! said:
Hey Rich! The blue smoke isn't upon start-up only....it's off idle, every time. If that makes any difference to ya.
My understanding is that would point to the turbo seals. And do double check the polarity of the coilpack connectors...

Take care and cheers
Rich
 
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