Failed upgrade to new 3"downpipe and resulting problems

[kjhansen]

OK, so I have a 3" downpipe on my PTE 5858 turbo already.  But the wastegate was stuck shut--good and hard.  Rather than break it trying to fix it, then ordering a new downpipe, I figured I'd just order a new downpipe.  Ordered one from RJC Racing.  They seem to have a good reputation.
I had to wait 2 months to get it, but it came.  Took it to my muffler guy and he could not make it fit.  No matter how much he twisted and turned it, it would sit on the bushing on the passenger side A-Arm and contact the inner fender well where it's plastic.  Plus he broke one wrench and three of the four bolts that attached it old downpipe to the turbo taking the old downpipe out. 
So he went ahead and put the old downpipe back in after putting studs in the bolt holes on the turbo. He had worked and worked on the wastegate and said it should work... maybe.  Only thing is, he accidently knocked the number 4 spark plug wire off.  He didn't notice this because he just pulled the car out of the garage and into the driveway--just  a few yards.  This was late Friday night. 
When I picked up the car and pulled out of his place of business I certainly noticed, but it was too late to do anything about it, so I went ahead and drove it home.  It had no power, bucked and stuttered and almost died more than once.  I immediately knew something was wrong of course, but I just had to get home.  After leaving town the speed limit went up to 45 so I sped up.  After it shifted gears into 4th it locked up the torque convertor, like it's supposed to do, and that caused the engine to lug and stutter. I got home all right, but was very unhappy.
The next morning (today, Saturday July 3rd) I inspected the car and found the disconnected spark plug wire.  I hooked it back up and started the car.  It ran much better and the wastegate seems to work--sort of.  Supposedly it was set for 21psi of boost before it froze shut, but now that it's "working" the car will only hit about 18 psi of boost. The adjustable rod length hasn't been changed.  It's as far back as it will go without cutting more threads.  But it has a flat spot in second gear where it doesn't seem to have much power and doesn't increase rpm like it should.  Then it hits third and pulls pretty good except that it backfires on the shift.
Anyway, I checked the TPS settings and they were pretty close, but I adjusted them to be spot-on.  Then I reprogramed the Turbo Tweak chip to the settings the previous owner had told me for an alcohol injected car running 21 psi of boost.  The battery had been disconnected so it needed that.
I'm at a loss.  All that was done was to remove and replace the old downpipe (and accidently disconnect the spark plug wire).  I know I was running 30psi of boost with the frozen-shut wastegate.  Could just the change in boost have messed everything up so much?  If so, what's to be done?
Keith
 

[Shimy87]

At 30 lbs boost. How bad was the knock and how long did you run it that way?

[kjhansen]

Actually knock wasn't that bad--you couldn't hear it anyway. Years ago. at a dragstrip, I had the boost control line pop off during a run and boost went up to 30psi+.  It knocked very loudly and I backed off immediately.  It was obvious what was happening.  This time it never knocked loudly enough to announce its presence.  I have a theory about that....
According to the previous owner, the stock valve springs have never been replaced on this engine and it has 190,000 miles on it.  I think that saved the head gaskets.  While the turbo pushed 30psi of boost, the valve springs were floating enough that a lot of it bled off.  Just a theory.  I didn't blow any head gaskets or break anything else with the few 30psi runs that I did.  Car has been running smooth and strong for the past 9 months with no 30psi runs.

When I realized the boost was set at 30psi I checked O2 and retard on the ScanMaster (using the recall function).  O2 was about 875 and retard was 4 degrees. 

I ran with that boost setting for a long time because I couldn't change it (wastegate frozen shut) but quit doing WOT blasts  immediately, i.e., as soon as I realized what was happening. I bought the car in September and made a few WOT runs but by October I had quit.  The previous owner had told me the turbo was set at 21psi and I believed that.  Let me tell you, there's a big difference in performance between 21psi and 30, boy howdy. When I punched it at 30psi I was too busy at first just staying on the road and going in a straight line to notice the boost gauge. 
 
So that's why I ordered the new downpipe--to get a functioning wastegate.  I didn't know what kind of downpipe the old one was or if I could get a replacement wastegate for it and if I did, I didn't know if anyone around here had the ability to install it. At 72 I'm not into getting down on the ground and working under the car anymore.  But there are not exactly a lot of Turbo Regal cars around here, or mechanics who know anything about them.

So yes, I ran the car with boost set at 30psi for quite a long time, BUT I didn't RUN 30psi very many times.  But I did run 20-24psi (watching the boost gauge) and didn't get any flat spots in second gear or any backfires on the shift into third.  And the torque convertor clutch was locking up smoothly and running smoothly until this latest incident.  I never did any WOT runs where I locked the torque converter manually either.

Long answer to a short question, but I wanted to cover all the bases.

[Shimy87]

My best advise is read Steve's Vortex buicks site , beginning to end. If you have one of these and plan on running that kind of boost your life will be better if you understand the basics of these. You end up with 2 options, find a guy that knows these cars to work on it for you, or learn as much as you can and fix things yourself. The first option will be hard to find. 

On your scanmaster readings, 875 is very rich to have a knock recall of 4 degrees.

Turn down the boost,, read the site, correct the basics. And go from there. People on here will help. Good luck!!

[~JM~]

https://www.vortexbuicks-etc.com

http://www.vortexbuicks-etc.com/BeforeModifying.html

http://www.gnttype.org (Lot of info here. Difficult to navigate though. Look at the "Resources" drop down menu)

http://www.gnttype.org/techarea/techpage.html  (Look at the drop down menu to the left) Do yourself a favor & Bookmark any of the articles you want to revisit so you can relocate them.

Turbobuick.com

Turbobuicks.co m (Note the "S" at the end. This forum appears inactive, but has many good posts with pictures intact)

(Hope it is not inappropriate to post links to other sites)

Sounds like you need a mechanic that is better acquainted with these cars. Also sounds like you may need new motor mounts & possibly new body bushings. If either, or both, are compressed due to age, exhaust parts alignment can suffer.

[kjhansen]

Shimy87, I appreciate your input. 
To clarify matters a little:  I owned a Turbo Buick for many years back in the 90s until 2009 and did almost all my own work. So I have an understanding of the basics--although Steve's Vortex articles are very good and I learn (or re-learn) from them still.  However I don't claim to be an expert, but I'm also not new to the car or its problems.
However, that was many years ago.  I am now 72 years old and have a very bad back.  This makes it very hard for me to get down under a car.  Pain is excruciating. 
Second, controlling the boost.  The whole point of replacing the downpipe was to make it so I COULD control the boost, as the wastegate on the old downpipe was NOT working.  I DON'T WANT TO RUN 30PSI OF BOOST.  And it is no longer doing that.  However, it's not because I got the new downpipe on.  I did not--or rather, my mechanic did not. It's got the old downpipe back on, but it's not running like it did before with the old downpipe on. It doesn't have the power it had before, and it's popping/backfiring at 18psi of boost and power is dropping off even more.  I removed the boost line from the turbo to the wastegate controller so it would run 30psi of boost again, but it will not.  Same symptoms.
Why?  How can I fix this?
It could be an exhaust leak before the turbo, where the downpipe attaches.  That would explain the loss of power.  I've had that happen before on my old TR.  It blew the gasket between the turbo and the headers.  But it didn't pop/stutter or backfire. I don't know if my muffler guy ever removed the turbo from the headers though.  I don't think he would have needed to.  In any case, in the past that only caused a drop off in power.  The engine still ran smoothly with no backfiring, etc.
Could it be an exhaust leak where the turbo and downpipe connect?  This is supposed to be a metal-to-metal connection, no gasket or gasket goop required.  The muffler guy did put high-temp exhaust gasket goop on it.  You can see the orange stuff.  Would that cause this kind of problem?  Could it be messing with the O2 sensor?
Could it be something electrical?  It feels like maybe, when the car is accelerating, and it backfires, that the engine is stalling and restarting very quickly and backfiring when it restarts.   That appears to be between shifts.  The transmission has a shift kit in it and shifts very firmly with a solid jerk.  Just now I took the car for a drive around the block (that's 4 miles out here in the country) to see if it would run over 18psi of boost after I disconnected the boost line to the boost controller. It should have, since there was no pressure to open the wastegate.  It didn't.  Still backfired, popped and stuttered at about 18psi.  Anyway, after I got back I opened the hood with the engine running to see if I could spot any physical problems, like soot around a turbo connection or broken wires.  No such luck.  So I closed the hood--firmly.  The hood struts are pretty new and give a lot of resistance.  When the hood closed, the engine stalled.  Very interesting.  Like there might be a loose electrical connection under the hood?  Could the disconnected sparkplug wire have caused damage to the engine when I drove it home?  It was only about 5 miles.
I was hoping someone on this board had experienced something like this.

[kjhansen]

~JM~ New motor mounts and all new body bushings (even some missing ones) were installed just about 3 years ago.  I definitely need a mechanic who knows these cars though.  I'm just not up to it anymore.

[xracerx13]

loose wire connection at the battery?

[Steve Wood]

driving the car with one plug not firing does not do the cylinder any good because the raw gas can wash the oil film off the cylinder wall and eat the rings on the piston up.  Hopefully five miles is not enough to do serious harm.  Pull the dipstick out and smell it...if it does not smell strongly of gas, it may not be bad.  If it does, about all you can do is change the oil.

Any time the O2 reads much above 800, then the car is way too rich and this abnormal combustion can set the knock sensor off.  If it is showing high 800's now, you have to figure out why and get it back to normal range.  Some times Eric's chips are a bit rich but not that much.  I guess check the maf numbers and see if they are reading high, that can cause it.  Maybe the O2 sensor is coated because it got to much raw fuel on it?  That could do it also.  You might trying starting car and seeing if holding in park at a higher rpm cleans it up...but I suspect pulling it out and replacing it, or at least cooking it with a propane torch if it looks blacked and coated.

I thought I saw some mention of high 800s but Now I don't see it...so the O2 may not be the problem. 

What I would do is check the resistance of the coil pack that had the disconnected plug.  Running these cars with disconnected plug wires can  blow the coil pack or the module pretty fast.

Most silicones  are sensor safe these days.  the sensor is below the joint so it should not be a silicone problem.

[Steve Wood]

Also make sure the spark plugs on question does not have a cracked insulatoe after being hit

[xracerx13]

true Steve on the plugs and coils but he said it stalled when he shut the hood hard.
Sounds like a loose battery cable to me.
He has not responded to that yet and I am very curious now 

Maybe ran a stereo amp wire near the hinge that's pinching?

[~JM~]

Is there any mention of what type of MAF is being run? Slam the hood & possibly smack the MAF?

Too difficult to diagnose without seeing.

[kjhansen]

I'm still stumped.  I did replace the TPS this morning because it wouldn't hold a reading--that's been going on for months though.  It wouldn't stay put on the low end.  I'd set it in the .40 to .42 range and by the end of the day it would be at .44 to .46. I don't know how that would affect the car's acceleration etc., but it does idle a bit better. .  But... I'm thinking it might be some kind ofelectrical/ignition problem in addition to the stuck wastegate.  Reason is
that in 4th gear and torque converter lock-up on a straight, flat road, I get a
stutter that feels like a miss.  Just cruising, no boost. When the torque converter isn't locked, the expected standard torque converter slippage smooths out the "miss."  The miss is new by the way.  Didn't do it before this mess started.  It's a mess miss.I reduced alcohol injection level because of the lower boost, and that has stopped the backfire on the 2-3 shift and smoothed out the flat spot in 2nd gear.  Still only 7psi of boost.

I checked the passenger side spark plugs and they looked great.  There was one spark plug wire loose on the passenger's side and one loose on the driver's side (not counting the one that was completely disconnected).  The connections were contacting the plug tops, they just were not on tight.  I pushed them on and got a solid click.  There feels like a minor improvement in drivability, but it's still not running much boost.  Seven psi max, and it's still got a slight miss at cruising speeds.    
  
It has a Delphi LT1 MAF sensor/Translator, which isn't mounted high enough to get hit by the hood, but I'll check the connections.  There is no aftermarket stereo installed, just the stock unit.  The battery connections are tight.  It also has a TPS/TEC box and a Casper's volt booster.

I did give the oil the old sniffer test (although I didn't do a taste test.  Yech).  Smelled like oil.  Oddly though, the oil is pretty black and it's only been a few hundred miles since an oil change with pure synthetic... and the zinc additive.

I did ohm out the coil packs.  The passenger side tower that has the #4 and #1 plugs on it ohmed at 11.6 or thereabouts. The #4 plug was the one that was disconnected completely.  The other two towers ohmed in the low 12s.  I found what looks like a brand new coil pack and ignition module in the spare parts I got with the car and it ohmed out pretty much the same, but I think I'll try putting it on tomorrow morning.  Something's causing this miss.  

As far as the boost is concerned I think I'm going to have to fix the downpipe I have.  So far I have $800 in this new downpipe and it still doesn't fit...  RJC Racing doesn't seem real interested in me returning it, but I haven't pushed them very hard.  Anybody want to buy a brand new RJC racing downpipe with the O2 sensor bung already installed?  $500 new, I'll let you have it for $400 plus shipping obo.  RJC swears it will fit any stock-style headers.  Anybody know a shop that will repair an existing wastegate on a generic downpipe?  The receipt I have for it is dated 2011 and is from Kirban Performance.  They have no records showing who their supplier was in 2011, no surprise.

[Steve Wood]

take the tps.tec off.  It does nothing but it could screw up something.  As long as the tps is set between .36-.46, it should not affect the idle once the engine has been shut off and restarted.  Floating around while running will make it feel different, however.

The tps/tec was sold in a day before people understood how the ecm fuels the engine.  It was a totally meaningless product but people did not know that then.

If the dp was bent by the exhaust guy while he was trying to make it fit, I don't thing you can expect RJC to take it back.

The ohms on the coil are in the usual range but that does not mean the module was not damaged.  No way to know if the coil and module you received are good or not...but I would try swapping them to see if it runs better or worse anyway.

[kjhansen]

Well, thanks to your suggestions and the fact that the previous owner had put a brand new coil pack and ignition module (already assembled) in the spare parts he sent me, the car is back to running well again.  Still 30psi of boost, but no longer a miss and is running strong. 
I was going to wait until morning when it's cooler and slightly less humid, but it's not that hard a job, so I just expended a little sweat and got it done.

So, anybody want to buy an RJC 3" downpipe with the O2 bung already on it?  Never had any exhaust run through it, and the muffler guy didn't bend it.  Make me an offer.