My New, New 347

[Turdle]

I might be way off base with this suggestion but when I was doing the initial tuning on our black truck ( years ago) James had a vin file incorrect in the tune, which shut down bank 2 . Some keystrokes and an email from him fixed it--

 

[Dono]

Jon, I keep having the same nagging feeling.
This makes the most sense to me. It was on my list tonight to revert to an old tune just to see.
Thank's for confirming that a tune can shut down bank 2. Extremely helpful, and your not off base at all.

 

[Dono]

Jon for the WIN!
I asked Decipha for help. Extremely responsive and knowledgeable guy that enjoys the tuning side of things.

I have all 8 cylinders, Narrow band O2's are in range for tuning, and the wideband is working.
Now I can actually get this thing driveable.

 

[Dono]

Here's a quick video with sound clip with idle air/fuel set. I still have tuning to do, and have not gone WOT yet.
I'm going to up the Drive idle some more in hopes of getting more vacuum. I'd say its almost dangerous right now with the low vacuum for the brakes. Failing that, I will be looking in to some kind of a vacuum brake assist system.

 

[vroomzoomboom]

that is low. like really low. mine has never dropped below 10. maybe ask dimas if he knows where it should be at at idle in gear. that or you might have the same problem i had a few years back where the tube going to the gauge kinked. i have even melted a tube making the vacuum reading false. regardless, good to know its hitting all 8 again. i am sure your neighbors will LOVE you when you calibrate the MAF to the injectors lol

 

[Dono]

I'll be driving my new motor to work tomorrow.

I know by how hard it is to push the brake peddle at very low speeds that the vacuum is not very good.
I need to check egr and pvc function. Dimas just doesn't think vacuum should be that low, the cam profile just isnt that much different than what I had.

 

[4pointslow]

Vacuum leaks or clogged cats come to mind, stuck open egr or Evap purge valve too.
Cant think of anything else right now.

 

[CDW6212R]

Was the distributor changed since it was on the dyno? Maybe the cam synch is off one tooth. Does it run any smoother if you raise the idle timing any, or a lot? That's the simplest thing I can think of.

 

[Dono]

Runs nice and smooth.
I set the cam sync myself with the correct tool. I know that's not it.
Here's a vacuum routing diagram I found on this site, I had the EGR Vacuum solenoid vacuum lines reversed. Apparently it does make a difference.

In driver, I have about 10 lbs vacuum now. I'm super happy with that. Also, with my egr not open all the time, tuning should be way easier.

 

[gmanpaint]

So.... The issues have been something simple after all. Bet that chin is up now

Congrats! All that hard work, patience, and perseverance has paid off.

 

[Dono]

Agree'd. I'm pretty happy. Even beyond the money for a vacuum pump. it was figuring out another place to mount it and the added complexity of yet another pump to fail.
I know you know my pain, and I know yours. Once we modify the crap out of something, the tweaking never ends.

 

[vroomzoomboom]

was this what we were talking about earlier?

 

[4pointslow]

That's a good one, I did that once to my truck too.
When the vacuum lines are hooked up like that it keeps the EGR valve open.
Glad you got it worked out already.
Now it should be fun time!

 

[Dono]

Tim, Yup. That pesky valve. I thought it was just a motorized valve that would open and close based on electrical input, but I think I was only partly right.
Now I need to un-do some tuning. On cold starts, the idle was hunting really bad. Now I know why. Maf transfer function is rich now, but not too bad.

The drive to work was fun in a good way. Boost came on nice and early. Pulls hard. There's been no hard pulls yet as I want to sneak up on that slowly and looking at the logs/adjusting each time. The manners are pretty good, and it should be an easy daily driver.

Tonight, I'll pull the belt off, give the crank a pull/push to check for obvious pain on the thrust bearing, and pull the oil filter for a look.

 

[vroomzoomboom]

oops i thought you ment the one on the tube coming off the header. then again, i also didnt know the ones you posted had a certain way of being put on

 

[Dono]

On the way home I was doing more wot testing and logging.
Solid 3lbs boost, which is where I have the boost controller set for now.

On the last leg home, something bad happened. I lost all power, I mean all. I could manage about 5mph at best.
I limped home to the garage, wondering what happened. The motor seemed to be ok, just couldn't get over idle.

First thing I did was pop the hood and look for a blown intake tube. This was very unlikely since there is only one connector between the throttle body and the maf. I do have a honeycomb in the tube before the maf to straighten the air, so I pulled that, but it was clear and no obstruction.
I started the truck, tube disconnected. Rev'd fine.

I worked my way back, under the truck, to the inlet of the intercooler. Look what I found....

Pic didn't turn out great, but this baggie was solid against the intercooler honeycomb. Mystery solved.
I went back to the air filter, wondering if it had somehow came off and a baggie from the road was sucked up. Nope. Filter was solid and intact.

So, it's all on me. The baggie must have been in an L pipe or U pipe when I was installing the bigger piping. oops.

I guess I get to delete my logs I made coming home today. Tomorrows a new day.

Oh, and I was pretty happy the honeycombs are there to help protect from stupidity.

 

[gmanpaint]

I would have had a stroke when it lost power. Lol

Glad that's all it was.

 

[Dono]

Iv'e had so much misery over this thing, I'm not getting terribly upset over what might be anymore.
As long as the motor stay's ok, and I don't wreak the truck I'm in ok shape.

 

[Turdle]

Sorry if this is a dumb question-
How much vacuum should this combo pull at idle? 10in seems real low to me, and may be too low for the vacuum powered items ( FPR-BRAKES- EGR solenoid-etc) to operate correctly.Does the supercharger create any boost at idle or should all vacuum be present?

Is the blow off controlled by vacuum also?

 

[Dono]

Ideal would be 18. I do get this when decelerating.
Yes, 10 is not great, but 4 was terrible.

Blow off is a pressure differential. So, when the throttle plate closes quickly, there's high pressure in the piping leading to the throttle plate, and low pressure in the intake manifold. The differential is what pops the valve open till the piping positive pressure goes down.

I'm sure it's the cam causing the vacuum issue. The turbo isn't creating boost at all at low rpm's. A turbo likes an engine under high load to start boosting. I don't have any vacuum leaks anymore, as I don't have that hunting idle on cold start up anymore. Famous last words , although finding another leak would be a cheap fix.

EGR was working, I confirmed it with those vacuum hoses reversed. The 10hg was holding the egr open just fine at idle, lol. The vacuum seems to be enough for the climate control.

Are the brakes super responsive and touchy with all that vacuum? errr.....no.
Are the brakes what I would consider dangerous now? no.
My options are not great for the brakes, its pretty much a cam swap or vacuum pump. I just want to get the thing tuned and drive it before I think about more expensive mods. The Volvo vacuum pump looks reasonably priced compared to other options, but then there's the finding a location for it, etc. I do reserve the right to change my mind though.