Geezus, I'm lost. Got the truck back together and went for a short drive, maybe 3 miles. It was dark and I don't see well at night. Plus, the instrument panel lights don't work. So, I'm trying to drive, look at TP on my phone, and watch the exhaust for smoke. Not doing any of them very well.

Don't realize that I had set the shifter into 3 rather than D, and I'm not really focused on that TP gauge. Obviously, the truck is very sluggish. Finally notice and shift to D, but the truck continues to use only 3rd and 5th gears. I head back to the house asap. I know it wasn't doing that the day I got all the black smoke. I consciously counted the gears changing as I left a traffic light.

The engine fan seemed to run too fast. When I first started it, the fan was normal, about 400-500. After a couple of minutes, I started off with EOT/ECT around 130, going real slow. The fan kicked in and got up to 2200 when I was barely driving 25-30mph. I assumed/hoped it just needed to get to WOT,.and it got there real fast - I'm assuming because it's hot outside still. But with EOT around 190, the fan was still kicking in over 2000. I didn't have the AC on at first, and still had the doghouse off. After about a mile, I pulled over and put the doghouse back on and turned the AC on. It had been running fast all day when I got the black smoke, but I didn't have my BAFX Bluetooth with me that day and can't say what engine temps were. It was pretty hot outside that day, and I had the AC running all the time.

Again, that info is kinda sketchy - I couldn't see. The part that's crazy is there are no codes. Nothing in TP, forescan. I got Forscan on my PC linked up and there are no codes. No transmission codes, no engine codes, nothing.

I'm not sure where to go, what to look for at this point.

Meanwhile, I'm still not getting boost above 2psi. VGT does fluctuate between 50-85, but when stopped and idling, it's at 85.

 

It may help us if you post some screen shots of all other vital parameters both koeo and koer. Also, would you mind share some photos of the weld to the pipes? If there are gaps anywhere, it may not produce pressure. Did you disconnect the transmission tube (dipstick), that may somehow cause contamination such as metal falling into it. It still doesn't explain the no code part. Even limped mode, it should have code, but that's wild guess without numbers.

 

Thanks. I haven't welded the pipes yet. Trying to make it run right before doing that. I'm using C-clamps still. They seem very tight, won't move at all, and I didn't smell fumes while driving slowly with the doghouse off. I'm about to go out and try again during daylight. Hydro had said there was a way to command the turbo with Forscan, but I don't know the app and don't see that function anywhere. I'll post data in a minute.

Random thought - I've swapped in the PCM from my 06 ambulance because one of the connectors wasn't grabbing the harness connector well. So, Forscan shows it as an 06.

 

Well, I apologize for panicking. It was night and I couldn't see.

The transmission seems to be shifting fine. The fan seems OK, although it's a lot cooler this morning. I never got on the freeway - not with just c-clamps holding my pipes - but the only smoke I saw was when I gave it a good pedal, and only a quick puff. I think that's to be expected on these big buses; they just don't accelerate well.

Forscan doesn't seem to have a Boost gauge? I'll go back and check with TP, but I expect it's the same. My VGT is the same - 85 at idle, fluctuating down to the 50s as I drive, usually in the low 60s.

All in all, it felt normal - maybe I've never had boost, lol. Here are the data pics. Sorry, can't figure out how to display in Farenheit, and I just threw in every PID that looked relevant.

KOEO


idling after start up

Idling after driving WOT

 

Since you say it drives normally now, maybe more test is needed to confirm that.
Other than that, athought I am a bit struggling with metric unit, a few data points I looked at appears fine. If you want to test turbo, the truck needs to be running at least 35 mph, and add some acceleration. I know it's hard to capture that, but idle only produces 1 psi in my opinion.

 

Thanks, namy. I did get it up to 35 and accelerated 3-4 times and saw a little puff of black smoke. but not the constant smoke I'd seen the other night. Unfortunately, Forscan doesn't show Boost. Need to do it again using TP, but I expect it will be the same - very little boost. I want to try commanding the turbo, just to confirm that it's functioning properly (unison turning the vanes), but it seemed to be OK when I inspected it out of the truck - the unison ring wasn't frozen. I don't know what other symptoms of a bad turbo could be - unison is free, vanes move, wheels/blades are all good. That means, I assume, that the solenoid is working.

So, I think it might be an external factor causing no boost - something causing the PCM to not command it on? however, I see the VGT% fluctuating, doesn't that mean it's being commanded? I've checked EBP and cleaned it, and the MAP hose and the CAC tube were all good. Only thing left I can think of is a PCM issue, or those exhaust manifolds not allowing pressure to build, or the down pipe connections at the turbo and EGR, although they look good.

I guess my plan is to test drive one more time to check Boost with TP, maybe get up on the freeway since the c-clamps seem to be holding, then move forward with the welds.

 

How about going into the options and set that stuff to Imperial and Fahrenheit -- would be easier for my old brain

Read the MAP to get your "boost" -- the "boost" gauge on the truck is (MAP_A - Baro) anyways

 

To me, what I see is that the EBP desired is 35, the actual EBP is 8, and the VGT % duty cycle is 85%.

Sounds like a turbo or VGT actuator problem.

 

I did change the settings to Imperial, and nothing changed. It said it would update on next connection to the vehicle, so I disco'ed and reconnected, but it was the same. Then, I shut down the app and reloaded/connected...no change. Then, I rebooted by computer, no change. I don't see a setting for Farenheit.

 

Thanks, Mark. I wonder if that could be due to leakage out the exhaust manifold connections? Dang, I didn't swap the turbo, since the vanes seemed to move easily. I wonder if it's just the actuator or the pigtail. One side of the connector clip is broken, but it seems to stay in place. Dang, I should have swapped in the other turbo, but I don't know anything about it, and it's been sitting unboxed for two years.

I wonder why it's not throwing any codes?

 

I forgot about the leak. That certainly could be the reason for the low EBP and high VGT Duty Cycle.

 

Is there a way to command VGT that confirms whether it works or not? Or can I apply voltage with my power probe? Any way to test it? I pushed the piston in while I had it out, and heard the vanes moving. It pushed easily. And, I didn't have a way to pull it back out, so I reinserted the plug and snap ring, and after reinstalling the turbo, I cranked the engine with the key off a couple of good times, and the piston pushed the plug back out.

How can I test the connector? Hate to pull the turbo again - what a PITA on this van - but I will if I have to. Second time is always easier.

 

I'm wondering if I might (I know, I know) wire the exhaust manifolds closed, rather than weld them. Would wire (maybe like a clothes hanger) burn through from the heat?

 

Pretty sure you can command the VGT from ForScan (full version).

 

I assume I got the Lite version since I didn't pay anything. It says Version 2.3.41. Any other way to know whether this turbo is good, or whether the spare one I have is good? I see now why you don't like dealing with turbos. I hate to have to break down and go buy a new/rebuilt one just because I don't know. Dang, the no codes thing is scary.