New Turbo Buick Owner - Frustrated with Knock read from Scanmaster, help appreciated

[Mike Licht]

When you do your recall on the SM hold the recall and press mode, that will give you the MPH that those two events happen at. Sometimes that makes it easy to sort out
Mike

 

[Ttype6]

Made two WOT passes
834 - 5.6 retard @ 16psi - no alky
808 - 11.7 retard @ 16psi- no alky

You dropped your fuel pressure from 50 to 43. This made you BLM number go from137 to 147.
This means your chip is adding more fuel to compensate for the fuel you took away by lowering the fuel pressure.
This is what the chip is supposed to do.
The chip is adding a lot more fuel than it should have to which makes me wonder if someone installed larger injectors without a different chip. The problem is that since you don't have a Powerlogger,we can't see what your injector duty cycle is.
We are also assuming that you have good fuel delivery because of the numbers we are seeing from the O2 sensor.
This is a dangerous assumption because the stock O2 sensor is not accurate at reading A/F ratio at WOT.
Your WOT O2 numbers went down when you turned off the alky and leaned out the fuel by lowering the fuel pressure. This caused you to see more spark retard.
Based on your numbers,I think your fuel system is good and your chip isn't commanding a long enough duty cycle.,but we need to verify fuel pressure at WOT.

Before you do another WOT I want you to turn your fuel pressure back up to 50 lbs,then put a guage on it to see what WOT fuel pressure is. When you do this I want you to monitor your MAF numbers on the Scanmaster.

 

[RmvBfrFlght]

Pulled all plugs, they all look good, normal in color and no sign of detonation

You may be chasing false knock. With the new set of plugs you just put in, pull them and check for detonation. Have some pictures of what to look for here:

http://dynamicefi.com/SparkPlug.php

RemoveBeforeFlight

 

[Ttype6]

You may be chasing false knock.

That is one possibility,but the way his O2 numbers climbed, in a previous post when he showed some spark retard,is consistent with a real event where the unburnt gasses,caused by a rapid and incomplete burn from spark knock,caused the O2 to read richer than the pull before with no knock and lower O2 numbers.

Since I'm leaning toward the chip,I'd like to see some WOT fuel pressure numbers first.
.

 

[Pronto]

Personally I would go with a TT alky chip for the adjustability regardless of the current issue. Of course he would have to verify what injectors, and other mods he has first. Sounds like the mods were done a while ago by the previous owner and it's possible that the OP does not have the corrrect info on what's been done to it.

 

[Hatdragracer]

WOT fuel pressure numbers first.
.

I hear ya...I am first trying to figure out the right connectors to get rid of the rail mounted gauge so I can use my actual gauge.

 

[Hatdragracer]

Personally I would go with a TT alky chip for the adjustability regardless of the current issue. Of course he would have to verify what injectors, and other mods he has first. Sounds like the mods were done a while ago by the previous owner and it's possible that the OP does not have the corrrect info on what's been done to it.

First off...I cant believe the amazing response from you guys...especially considering how new I am to Turbo Buicks...I greatly appreciate it and I am so excited to have the car I dreamt about in high school.

This detonation thing is keeping me up at night...especially since I traded a great running 69 Camaro SS396 for this Regal the "I told you so" from the wife would be unbearable if I blow the head gaskets.

I have been working up a spreadsheet on what different routes would cost. So far I like the idea so far as Pronto suggested of the TT Chip, and looking at their website the pacakges with the fuel injectors seem to be a great buy and would reduce a lot of the mystery of what is in the car. Other posters have deduced that their might be some issues with the MAF and/or the O2.

I visited 2 tuning shops today in Houston, I am completely shocked, as when I built my Turbo Z28 in 2002 it seemed like every other car there was a turbo buick, now it seems like all anyone wants to tune is an LS1!! Both shops strongly recommended Fast XFI, I am not completely sold as I am more familiar with Big Stuff 3, The Fast looks a little simpler to integrate with the Buicks factory harness.

I also think there are some hard parts I would greatly benefit from updating, especially the stock intercooler...at bare minimum for now I will be completing the "spring cleaning" post shared earlier.

I know there are already at least a dozen threads debating different stand alone FI systems so I will begin researching them.

Regardless I will update this thread with what direction I take...thanks again!

 

[Pronto]

Well, you might as well start at the begining and list all the mods that you "think" were done, you'll be suprised what people are sold. From there we can help you verify them and move on. The spring cleaning is an important first step. Here's a site that will keep you busy for a while http://www.vortexbuicks-etc.com/ You will find some good info on what the Scanmaster shows you and tuning. XFI is great system but you probably don't need to spend 2K plus a tune to get your car to run right. Lots of guys do just fine with the stock ecm and chips. There are several possibilities why you car is not running right that don't require an aftermarket system. You may have mismatched injectors or a bad MAF for example.

 

[Hatdragracer]

You may be chasing false knock. With the new set of plugs you just put in, pull them and check for detonation. Have some pictures of what to look for here:

http://dynamicefi.com/SparkPlug.php

RemoveBeforeFlight

Thanks for the link...upon closer inspection of the newer plugs I definitely see some speckling of the porcelain...I was looking for the classic purple I would see on my LS1's

 

[Hatdragracer]

Also...just occurred to me...the car ran great when I first got it from the PO couple weeks ago (without alky, 17lbs of boost)...the only thing I did before these detonation issues showed up was refill the gas. I bought Shell premium 93, so I will try premium from another station once I get down to 1/4 tank. I will also put the fuel press back and see if the fuel could possibly be the issue. The simple stuff first right!

 

[2toneNV]

Ryan,

I don't really understand how you are having these problems with the car, but the first upgrade I would do would be a fuel pump and hotwire kit. I think I might have a new hotwire kit still in the box and unused that I will give you a god deal on. Also, I have had some 83lb injectors cleaned and flow matched by Chuck Leeper from this board that I haven't installed in the GN. When I do this I will have some 60lb Mototron injectors and still have the TT chip that was burned for the 60lb.injectors that I would sell you also. Like Pronto said there is no need to go XFI or BS3 on that car. The addition of the 60lb injectors, TT chip and hotwire kit should be the upgrades at the top of your list. These would get your fuel system to where you want it and have plenty for future upgrades.
I will look through my numerous boxes of parts for another stock MAF because I replaced the stock MAF on my GN before I went to my XFI and it is known good(thought that was the one I gave you).

 

[Hatdragracer]

Craig..no worries....I traded a 43 year old car for your 25 year old car...I knew there would be risks and I know you would never misrepresent the car. I certainly appreciate any advice you can offer...maybe one day I can help you with the "Barny Rubble" car...yeah that's right...I saw that comment!

 

[Jerryl]

Also...just occurred to me...the car ran great when I first got it from the PO couple weeks ago (without alky, 17lbs of boost)...the only thing I did before these detonation issues showed up was refill the gas. I bought Shell premium 93, so I will try premium from another station once I get down to 1/4 tank. I will also put the fuel press back and see if the fuel could possibly be the issue. The simple stuff first right!

I had that happen twice.
Find a station and add 3 gallons of E85.
If KR goes away, you know it's not false.

 

[Ttype6]

The only thing I did before these detonation issues showed up was refill the gas.

I will try premium from another station once I get down to 1/4 tank. I will also put the fuel press back and see if the fuel could possibly be the issue. The simple stuff first right!

Yah,we're all so great with our info,but none of us thought to ask about your gasoline situation.
This is a very important piece of information.
Your O2s indicate that you don't have a fuel delivery problem,but it's always nice to see it on a gauge.

New information=new plan.
Go to the hardware store and purchase 2 gallons of xylene and poor them into your gas tank.
Drive the car and report back.
Don't let the car heat up to 104 when you run it.

Oops,I posted before I saw the comment by Jerryl.
This would be a lot cheaper.
We're trying to increase octane to see if you have bad gas.
Talk about simple.

 

[Jerryl]

Yah,we're all so great with our info,but none of us thought to ask about your gasoline situation.
This is a very important piece of information. . . . . .

Well . . . I think you guys are doing a GREAT job.
The Devil . . . aka detonation . . . is in the details . . . and those are sometimes taken for granted because we are working on next level stuff . . .

 

[Ttype6]

I also can't stand the thought of you flooring it one more time and seeing all that spark retard.

 

[Ttype6]

Oh,and one more thing,you'll never need anything other than the factory computer.

 

[Ttype6]

I hear ya...I am first trying to figure out the right connectors to get rid of the rail mounted gauge so I can use my actual gauge.

You can,simply take the schrader out of the end of the fuel rail,install some rubber hose and clamp it to the rail and the gauge.

 

[Hatdragracer]

New information=new plan.
Go to the hardware store and purchase 2 gallons of xylene and poor them into your gas tank.
Drive the car and report back.
Don't let the car heat up to 104 when you run it.
.

E85 has always bothered me....never looked into Xylene...but I will now.
What do you mean "Dont let the car heat up to 104...with the AC on the Coolant temp stabilized today at 204 on a 97 degree day? I cant drive around the block without getting it above 104?

 

[Ttype6]

E85 has always bothered me....never looked into Xylene...but I will now.
What do you mean "Dont let the car heat up to 104...with the AC on the Coolant temp stabilized today at 204 on a 97 degree day? I cant drive around the block without getting it above 104?

I meant to say 204. Don't turn the air on.
I,m now concerned that you have bad gas.Xylene is an awesome octane booster as it is 117 octane and high octane unleaded contains it in its blends. It costs !8-19 dollars a gallon.

Three gallons of E 85 will cost you $9.00 or less. E 85 will not hurt your car in any way. It will lean it out a little,so if you have a fuel delivery problem it would get worse. I don't think you do,but the gauge will tell us that.

If you don't mind spending the money I would lean towards the xylene.