Penglii's 1989 TGP

[Garrett Powered]

that happens so much to me. I finally got a mint set of those lines on my red car (since they dont sell those anymore) and I snapped one of the lines by accident.

 

 

 

fuuuuuu!

 

now it has one of those rubber couplers. when you buy those, try and find a variety pack of them. or just buy a few of each kind. you will use them all up dont worry.

 

you should remove the air filter and wiggle the turbo shaft. it should be TIGHT in there. if not its why you are smoking.

[Penglii]

Update:

 

Repairing that busted line helped a bunch... but she still smokes some after getting up to full operating temp for a minute or two, which leads me to think maybe the oil return line is warming up and collapsing. The new return line will be here on Monday. Fortunately I don't have much driving to do this weekend.

 

I checked the trans modulator line for signs of fluid, it seems dry... so I'm gonna wait to install the new one when I change out the oil return.

 

Checked the turbo for shaft play... there was a tiny bit of side to side play (engine was cold, so maybe its ok) and no up/down or in/out play. Spins freely, does not hit the housing, and everything looks clean.

[White93z34]

Is your oil return line original? Replace it if you have not already. my old TGP would billow smoke. I pulled off the oil return hose and the inner lining of it was starting to collapse it didn't look *that* bad but I replaced it and that was the last time it blew clouds of smoke.

 

http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Store_Code=tp&Product_Code=ATP-OIL-024&Category_Code=

 

That stuff is heinously overpriced when you include shipping, but it is apparently what is right for the job. I used some hi-temp heater hose on my old car but it got totaled before I could find out if it was a bad idea or not.

[Penglii]

Is your oil return line original? Replace it if you have not already.

 

My new oil return line should be arriving today, hopefully I'll have a chance to install it this evening.

 

A quick question though:

Where the line connects to the oilpan, can that be reached from above? Or only from below?

[White93z34]

I removed the air filter and it gave me enough access to do it from the top.

[Penglii]

The new Oil Return line helped a lot.

The old one I pulled out was not the original line... but it was a piece of regular fuel hose.

 

Now there is less smoke, it mostly looks white and does not smell like coolant... I'm thinking Trans Modulator even though I cannot find any indication of fluid in the line.

I should have replaced it when I was doing the return line, but the mosquitos were killing me and I could not find the nut that holds it in.

I understand it is on the PASSENGER side of the modulator?

There is like 21 years of accumulated grime in that area, so it is extra hard to feel around for that nut.

[stockgp]

That stuff is heinously overpriced when you include shipping

 

an 18 inch section cost me 16.50 from napa... just fyi

[WhatTheFehl]

It looks like the same shit we carried at Dyke... We sold it for $9 a foot IIRC... we carried it because it was used in emissions testing equipment that our customers had.

[Penglii]

I got a foot of high-temp reinforced silicone tubing for something like 10 bucks shipped. Not as heavy duty as the stuff APT turbo sells, but I understand it will do the trick.

[Garrett Powered]

you won't notice any difference. its not high pressure or anything so it just needs silicone and lightly reinforced.

 

I have used both and wouldn't think twice about saving the extra money.

[stockgp]

do any of you guys have a pic of your failed line? i just replace mine, and it looks brand new. well, aside from some oil inside.

[White93z34]

I think I still have the bad one I took off my black tgp. if i find it i'll post a picture.

[stockgp]

[Penglii]

OK... Replaced all 6 plugs... turns out she was running R44LTSM's. Fortunately it was only for the past few months. Got the correct ones now.

Replaced the PCV too while I was doing the back plugs.

 

Finally got the Trans Modulator replaced too... but I'm not entirely sure the metal rod is back in the right way. It seems like the only way it fits... but I wish I remembered to keep track of which way it was facing when I pulled it out. But alas I was distracted by my magnet wand breaking in half.

 

I broke one of the strut tower plate studs when I was putting the FSTB back on... but I don't think that is a major concern right now.

 

I was going to change the oil too, but I ran out of time... had to go watch some fireworks.

I did have time to let her idle for a few minutes... and no smoke so far. *knocks on wood*

Edit: I'm a dumbass sometimes... I just searched around and found pics of the instructions that come with APT modulators and it answered all of my questions. The picture I took would be installing it backwards, but the way I actually installed it is correct. WIN!

Edited July 4, 2010 by Penglii
was being dumb

[Penglii]

OK, changed the oil the other day and made some more progress tonight.

Installed new Denso O2 sensor, performed an idle relearn, and played around some with the Tech-1a.

Discovered that my IAC is good, the EGR seems fine, my Wastegate checks out, and my TPS is perfect.

No codes are stored.

Battery is OK... but just barely.

 

Still smoking, just as much as ever... a lingering smoke, randomly varying in the rate it's released... the color is a light grey/almost blue/white mix and I cannot pinpoint the smell at all. Not strong smelling. I don't think it smells anything like coolant... but it does not smell like oil or gas either. It smells sort of like burnt rye bread?

 

Also noticed that my MAT wires are exposed and nasty looking right where they meet the connector... I wonder if that is causing problems of some sort. What is a normal temperature reading for that at idle on a muggy summer's evening in Wisconsin?

Edited July 10, 2010 by Penglii

[White93z34]

i don't know if you mentioned this before, but what kinda shape if your turbo in? endshaft in/out, up down play?

[Penglii]

i don't know if you mentioned this before, but what kinda shape if your turbo in? endshaft in/out, up down play?

 

I'm not sure if I mentioned everything either... but...

 

I checked the turbo for play... and it has Zero up/down play and Zero in/out play... but slight side/side play (which is probably my problem).

I have also replaced the Crossover, replaced the IAC, replaced the O2, replaced the PCV, replaced the Trans Modulator, replaced the Turbo Oil Return Line, replaced the Spark Plugs, replaced the battery, verified the Alternator, verified the Coilpacks, verified the Plug Wires, verified the TPS, verified the rusty-looking EGR and performed Idle Relearn a few times.

 

After all that there is still smoke. It smells slightly like oil and slightly like gas, but does not look/smell like a rich-running over-oiled lawnmower either.

 

I have not yet checked the injectors or replaced the bad oil pressure sensor.

 

The previous owner personally did a great job rebuilding the engine less than 1500 miles ago. He changed the oil/filter with Mobil-1 a couple of times and I have changed the oil/filter with Mobil-1 5W-30/PF-52 once so far. He also replaced the Turbo because it smoked... although I do not know if he got it rebuilt or replaced it outright. I am suspecting he got an unlucky unsuccessful rebuild.

 

He had N/A 3.1 Plugs in... but I have replaced those with proper Turbo OEM plugs.

 

I have not checked the injectors or replaced the bad oil pressure sender yet.

Her ECM is a scrapyard unit from a 3.1 Lumina... it says so on the side in china marker... but she seems to have a Stock TGP Chip.

 

I still need to get a TopGun160 chip from someone... and the associated 160* T-Stat and K&N Filter & K&N Breather... but I doubt those would fix my smoking.

 

At this point I am thinking I am going to have to replace/upgrade the Turbo... hopefully she can keep the smoke to a minimum until I can somehow find the cash to get a nice new Turbo somehow.

Edited July 11, 2010 by Penglii

[White93z34]

very odd that its smoking when the turbo has no play to it. my red tgp will smoke pretty good but I'm pretty sure that has something to do with my really loose turbo.

 

does it smoke on startup? after you rev the engine? what are the circumstances that it will smoke?

[RobertISaar]

i can round up a TG160........

 

and what kind of oil pressure are you seeing? if the pump is working 'too well' it could be pushing oil past the seals in the center housing, causing that smoke... if so, you'll need a restrictor in the oil supply line.

[Penglii]

does it smoke on startup? after you rev the engine? what are the circumstances that it will smoke?

Does not smoke immediately on startup. I have not verified this, but it almost seems like it only smokes in Closed Loop.

From a cold start, idling, she takes maybe 30 seconds to start smoking. From a warm start she smokes sooner, but still not immediately.

Smokes at idle and at low RPMS when moving slowly... when she is smoking and I hit the gas the smoke increases for a second and then tapers off as I go down the road. At idle I cannot tell if it is a steady flow of smoke or not, it seems to fluctuate in intensity.

 

Sometimes there is little/no smoke and sometimes there is a bunch... I cannot determine a pattern, but I suspect hot/humid weather increases the smoke.

 

i can round up a TG160........

Awesome

 

and what kind of oil pressure are you seeing? if the pump is working 'too well' it could be pushing oil past the seals in the center housing, causing that smoke... if so, you'll need a restrictor in the oil supply line.

I am not positive what the oil pressure is, since the sending unit is bad. Usually the gauge is pegged past max, but sometimes during idle it will sort of decide to work... and when that happens it reads about 35. Don't know how accurate that is though.

 

An oil restrictor is definitely worth a shot, but I don't know what to look for or where to get one...

Edited July 11, 2010 by Penglii

[RobertISaar]

30 seconds when cold may not get you into closed loop...

 

stock values from the AZRC BIN(latest TGP BIN from GM that i have)

 

timer determination temp:

 

coolant less than 58.55*F at startup, use cold timer

coolant greater than 158.45*F at startup, use hot timer

between is warm timer.

 

cold timer: 180 seconds

warm timer: 32 seconds

hot timer: 6 seconds

 

if at idle, another 13 seconds is allowed for the O2 to start reacting before setting an O2 error code. air temp must also be above -20*F and coolant temp must also be above 80*F to allow closed loop fueling.

 

it almost sounds like oil is being drawn into the intake, and then burnt when you have your foot off of it due to vacuum... may wanna pull the intake tubing and see if you can find a shitton of oil in the intake through the TB.

[Penglii]

30 seconds when cold may not get you into closed loop...

Good call... based on the weather outside I cannot imagine the coolant getting as low as 58.55*F... so my "cold" starts are probably actually "warm" starts.

It does certainly take longer to smoke on cooler mornings, but I have not kept track close enough to say anything for sure.

Open/Closed loop probably is not a factor here.

 

it almost sounds like oil is being drawn into the intake, and then burnt when you have your foot off of it due to vacuum... may wanna pull the intake tubing and see if you can find a shitton of oil in the intake through the TB.

The intake and TB look clean. Maybe a light dingy film will wipe off, but nothing obvious.

[Penglii]

Upon closer inspection the TB is pretty clean.

 

Checked the turbo for play again, and I think I accidentally lied earlier. Still ZERO in/out play... a little side/side play... and a little up/down play. It spins freely and does not hit or rub the housing.

 

I did notice a little oil on the air filter side, as well as some in the air cleaner pipe. It looks like it is coming from the PCV breather tube on the air filter. There is telltale residue on the filter from where oil comes into the air cleaner box from the breather, sits for a second on the rubber air filter gasket, and gets sucked into the turbo.

Maybe a Breather Filter would help?

But why would excessive oil be coming from the breather (PCV is good)... and why does the stock airbox just allow it straight into the intake stream??

[mfewtrail]

Excess oil through the PCV is usually caused by poorly sealing rings. If that's the case, the car should smoke on hard acceleration, but may not be noticeable to you as a driver because the wind @ speed is going to disperse the smoke making it more difficult to see. Someone following behind you should be able to see it pretty easily though. If it was burning a large amount of oil, you'd have a big mess in the stock airbox instead of a light film...and your oil level would be noticeably dropping if you check it on a level surface when cold.

[Penglii]

Excess oil through the PCV is usually caused by poorly sealing rings. If that's the case, the car should smoke on hard acceleration, but may not be noticeable to you as a driver because the wind @ speed is going to disperse the smoke making it more difficult to see. Someone following behind you should be able to see it pretty easily though. If it was burning a large amount of oil, you'd have a big mess in the stock airbox instead of a light film...and your oil level would be noticeably dropping if you check it on a level surface when cold.

 

Well I think I have ruled out PCV blowby... I cleaned up the lines and fittings and whatnot, and then went for a drive with an observer following me. Still smoking, varying somewhat randomly between light and heavy... going down the road at speed leaves a light smokescreen... but hard acceleration seems to make the smoking ease up temporarily.

Checked the PCV breather piping and it was still clean... no big mess in the airbox or anything.