the.jack

Catted DP did not fix the issue. I'm actually getting the 2178 code sooner than before

I need to confirm the MAPs are seeing a similar boost level and there's not a leak. Still not sure why a boost leak would manifest itself worse at idle than under load, but I'm not sure where else to go without just replacing parts willy-nilly (have major work on another vehicle this month, so it's not in the budget anyway...)

firemangeorge

Shouldn't be any boost at idle. In fact, at idle it should show vacuum.

the.jack

This was my concern as well...

But after a long phone conversation (for a vendor support call, at least), ZZP reviewed my original submission and apparently I'd checked a wrong box on the tune request form!!! They had tuned it for the MAF in a different location. Given pressure / flow and cross-section being parameters (or arriving at a value - I haven't see the tune software myself) I can understand this being an issue.

So... I'm sending my ECU back for a correction.

I hate to be a jerk, especially to Hahn who has given me great service, but the ZZP tune was more fun (and much smoother) working poorly than Trifecta's tune working "properly" :/

Hopefully this can be covered by next week... My inspection is up this month!

the.jack

First, ZZP came through with some great tech and customer support so far... Now to the bad news: after a retune because of poorly identified MAF configuration on my part, it's running without a light, but it is still throwing codes and "cruise" throttle is constantly pulsing minor boost surges which is really annoying and probably not the greatest for the BOV. Right now I just need to get enough miles to pass NYS inspection and then I'll circle back to hopefully smooth out the issue. It might be time for an HP Tuner, but I want to talk with ZZP one last time before taking the plunge.

donbrew

If it is throwing codes, but no CEL miles won't reset the "not ready for I/M". Certain codes will prevent the OBDII tests to complete.

"too rich" can damage the cat and is definitely an emissions fail.

I don't recall what you have done so far, but here is a good link to the code:
P2178 System Too Rich At Off Idle Right Bank | AutoCodes

the.jack

I'm on to other codes but what you say makes sense. I keep popping a P0108 MAP reading high input. It sounds like the most likely issue is a vacuum line leak somewhere. I'm into my 10-day extensive sticker for inspection... Isn't that always the time you get codes?

But the rich has been totally cleared by the new tune, so I believe the cat will be safe at this point (definitely a concern I had with the rich error).

What's interesting is that this time around it's running well when you're on the gas without going in to limp mode or showing hesitation. It's pretty darn snappy at this point, I just need to prevent this code so I can get it inspected!

I'll review the vacuum lines tomorrow. In all my digging around it's entirely possible I loosened something. Crossing my fingers that's all it is...

the.jack

A ha! I KNEW this would cause a problem someday I just didn't expect it so soon. That top MAP sensor was ****ed, badly. Once I followed the problem to manifold MAP sensor (GMS1) which was a replacement when I was troubleshooting earlier I removed it and inspected it: the o-ring was deeply creased on one side and day as a bone on the other! Clearly air was passing through (and in both directions).

New o-ring? Check. But since I hated installing the sensor the first time and I really hated installing that sensor the second time I decided to avoid adding to the definition of insanity, took my side drill bit for my Rotozip and hogged out just a little material from the mounting sleeve on the sensor so the bolt would actually align with the stock setting. BAM! I pressed the sensor in nice and flush with one hand, nutted the mounting bolt straight and even with a small ratchet in the other did not require stupid torque on a plastic sensor to seat squarely and it now sits flush and beautiful in its natural habitat.

I cleared my codes and took a ride massive difference, plus not a single code after 20 min of driving in mixed roads, stops, slow speeds, high speeds, light cruising and WOT as well.

After my commute tomorrow I should be ready for inspection.

That friggin' sensor not really fitting... What was GM thinking? A cob-shop, sure I can see that. But the OEM "designs" an upgrade package with sensors that eh... sorta fit? Ugh.

Clearly it can be installed without the mods: the first time I put that in it lasted 30,000 mi, but I didn't even like looking at it under the hood, seeing it visually not quite fitting properly. Ugly.

firemangeorge

Not exactly sure why you had to modify it there to make the sensor fit.

The Stage 1 3 bar sensors themselves have to be modified BEFORE they are installed. There is a small tab on the mounting side that has to be ground off so the sensor will fit flush.
Any chance you are not removing that tab before installing ?

the.jack

Chance? Sure. But my problem wasn't a flush mount but the holes not lining up. And I've had several units (different orders), all with this issue so it wasn't a bad batch.

And even if grinding a tab is/was an issue... For a kit that costs $600-800 from GM (GMS1, not just the parts obviously) it should not be a concern. That business should be plug and play!

Oh well. It's over now. Almost all of my statuses are ready for inspection. One more commute should do it and she's running like a champ. Was chasing a rice rocket (keeping distance, of course!) down the country roads today. I've never been able to keep up that well.

the.jack

In looking at the sensor I pulled out, I do recall the tab grinding. But what I ended up doing working really well. I never liked how the original mod "felt" during installation, this way kept everything nicely in line.

I'll try to take a macro of what doing neither does to the sensor. In particular you can see it was clearly not sitting squarely by the (still present) crimping of the o-ring shape.