Powerlogger installed, have a knock problem

[cchilly]

Hi

I'm looking for some guidence with this. I bought the car in the fall and really haven't driven it much since I have had it. Anyway, I bought a powerlogger and started playing with it this weekend. I did a run up to about 60 and got knock in the middle of first and all of second. KR went to 12. O2 starts at 860 and goes down to 740. It seems my TPS is a little low, but I'm guessing this isn't causing it. The boost spike was to about 19 and then settled back to around 16 or 17. I'm running Sunoco 93.
The car has a Red's 93 chip. It looks like they put on a small air compressor regulator to adjust the boost. It is a small plastic regulator that has ARO on the side of it. The vac line goes in and then looks like it just vents out on the other side. I have not touched it since I bought the car. I have a walbro 340 that I just put in with a FT hot wire kit. I adjusted the fuel pressure to 43 and varified that the FP climbs 1:1 with boost with an electronic Snap-on guage.
I don't actually hear any knock when running it. Should I hear it?
Can some one give me suggestions on what is wrong? Is it just too much boost for 93 gas?

Here is my powerlogger file for those who would like to see it. Also, I have factory injectors and they are at 150% duty? Does this seem right?

I have 60lb injectors and a TT chip, but I want to make sure the car is good before I start throwing parts at it. I would also like to take it to the track and make a basline pass before I start adding parts.

How can you post the powerlogger file? I compressed into a zip, but now the file size is a little to big. How can I make it smaller to post?

Thanks
Chris

 

[fullahotair]

150% duty cycle is way out of wack, did you say it was a stock turbo?? I have 42.5lb injector with a CPt-61, and my duty cycle is 90% or something in that neighborhood. Have you confirmed the p'logger was installed properly and the chip is burnt for you combo? Has the driveability of the car changed once you installed the p'logger?

Can you/have you made any changes that change the knock values or duty cycle? i.e. turn the boost way down low and see what the knock values do?


you have the zip part right, but you can't compress the file anymore than that...you just have to record a shorter run.


Nate

 

[cchilly]

Hi Nate

Yes, it has a stock turbo. Or that it was sold to me as.

How would I confirm the powerlogger is installed properly? It seems to be working fine. Most numbers seem right/realistic, so I think that part is working ok.

The chip came with the car, so I guess it is the right one. It seems to run fine. The car runs the same since I installed the powerlogger. I don't hear any knock, so unless you use the scan tool, you would say the car runs fine.

I have not done anything else to the car since yesterday. I didn't have time to start messing with the boost, so I just put it back in the garage for now.

If anyone would like to see my data I can email it to them.

Thanks
Chris

 

[fullahotair]

You can send me the powerlogger file ( speedst83@aol.com )and I can take a look at it tonight to see if anything jumps out at me.

What are you current mods (the one the powerlogger was recording)

stock chip? injectors? turbo etc??

You have 60lbers and TT chip, but they aren't installed yet?

Nate

 

[cchilly]

Hi Nate

I just sent the file.

The car has a Red's 93 chip, stock injectors and stock turbo. Boost is set at 16 psi. I have a Walbro 340 with a hot wire kit installed.


You are correct, I have new 60's and a TT chip for them, but they are currently not installed.

I would like to get this corrected and go to the track to get a baseline time before I put any parts into it. I just don't want to blow a headgasket doing it.


Thanks
Chris

 

[TurboDave]

Something's amiss. Could be real knock, but hard to tell.

Since you already have the TT chip and 60# injectors, I would HIGHLY recommend you go ahead and install them.

Gotta be better than that RA chip!!!!!

 

[fullahotair]

Hi Chris I got your file. I would take Dave's advice and put in those 60lbers and TT chip. That will allow you to see what effect that has on your situation. Dave has helped me out a ton and so I would take his advice without hesitation.

Swapping out the injectors with the 60's and TT that you know is burnt for those injectors will help eliminate the unknowns.

I also noticed you were in Power Enrichment mode but your TPS sensor was relatively low at about 3.9 V. I think as long as you get into PE mode, it is considered WOT, but you might want to think about adjusting the TPS.

Also noticed your PL file indicates you are constantly in 4th gear. You shift linkage must be off?

Swap out the injectors/chip and report back...I am curious as to what effect that has...

Nate

 

[cchilly]

Thanks everyone for all the help.

It looks like the 60's will be going in with the TT chip. I just need to find the time to do it.

I will fix the TPS when doing the injectors.

I think it reads that I'm in 4th because the TCC solenoid is unplugged. I have a new one of those to put in as well. I happened to notice it was unplugged and when I plugged it in the converter would lock in second gear and start lugging the engine.

I will let you know the outcome once I get the new injectors in.

Chris

 

[onefastgn]

Just checking into trend.

 

[cchilly]

What do you mean?

 

[fullahotair]

He is just "subscribing" to the thread to keep tabs on what the outcome is...


Nate

 

[cchilly]

I see, I thought he was saying there was a trend to my problems.

The plan is to do the injectors and chip on Sunday. I will report back with results.

Chris

 

[cchilly]

Update

Well I put the 60 pound injectors in and the TT street chip last night.

The knock seems to be better, well at least the only knock I would say I'm getting is false. It happens when I let off the throttle and also it looks to do it between the 1st and 2nd shift. KR is roughly 2 at both times. O2 is roughly 800. Injector duty goes to 50% at the top of 1st.

I do have a different problem. Well maybe it is a question. The only thing I changed was the injectors and chip and now my boost goes to 12 psi and that is it. I haven't changed the boost controller at all, but before putting in the new injectors and chip I was at 16-17 psi. Would the installation change the amount of boost?

I haven't moved the boost back to 16 psi yet. I wanted to get some opinions before messing with it.

Thanks
Chris

 

[jasjamz]

Did you address the tps issue also? If so... crank it up! I go two psi at a time. Watch for knock

 

[cchilly]

Yes, thanks for reminding me about posting that.

TPS is .46 at idle, 4.2 at WOT. I had a tough time trying to get WOT higher than that while keeping the idle down.

So I will start adding boost then. Any thoughts on why it went down? Anyone fimilar with the air regulator style boost controller. I'm wondering how much I turn to go up in boost. I'm assuming I turn it out to increase boost?


Also, the new set up runs great. If anyone is on the fence about a TT chip, just go for it. The car idles and just plain drives much better than before. Big improvment so far.:biggrin:


Chris

 

[GNVYUS 1]

CChilly you sound like your background is N/A old muscle cars with how you view knock as being an issue if you only hear it. With the way the cars been knocking you're on borrowed time with a head gasket or bearings since it's probably been doing that for a while ( been there on my 1st GN when the previous owner had left it alone and running at 18psi ). Here are some tips to help keep you driving the GN more and less of it sitting in your garage all messed up.

1) Spend a lot of time reading up on these cars, their tendencies and don't get greedy until you KNOW it's going to be ok.

2) TUNE FOR ZERO KNOCK AT WOT.

Don't even bother adding more psi with 93 octane on a stock GN already at 16-17psi considering we know very little about your build and especially timing.

2 degrees of knock on a shift is normal and get a powerplate. Don't sweat over the TPS at WOT, when it's in PE it doesn't matter anymore. 150% Duty cycle is off the board crazy, anything around 90% could use an upgrade in size or alky etc, I wonder if it's not the stock turbo.

12psi is what the stock actuator is set at so you might have some issue with the solenoid hose or sensor etc.

 

[cchilly]

Mike

Thanks for the advice. This is my first GN, but I have been doing a lot of reading like you said. My last ride was a 66 nova that ran 9's off the bottle, so yes I have more knowledge of older engines. Mainly Chevy's.

Anyway, I understand about the no knock. It seems like I'm there now. My question is why did I lose boost when I change to bigger injectors and the TT chip? I have a boost controller to add additional boost, but that was not touched. I'm not looking to add boost above the 16 psi, but right now I'm at 12, so that seems a little low to me.

I also have a powerplate(not installed), but I wanted to get a baseline before I added any upgrades.

The combo of the car is basically stock, has 43K miles. Well now I have 60# injectors and a TT chip. K&N filter set up, but I really don't consider that a mod.

I would like to take the car to the track in the next few weeks before the season is finished. This way I can get a baseline before adding mods.

Boy, I hope its a stock turbo. The car goes good, but not that good.

 

[GNVYUS 1]

Nova's are cool cars but unlike how you listen for pinging in an N/A car you don't want to see any knock on your scan tool and if you hear it well, you're probably done. With the cylinder pressure being so high on a Forced Induction car you can't afford knock.

Powerplate is not really a power mod so add it and then dial in your tune. With it equalizing all the cylinders it will make your AF/R readings more accurate since you can determine the cylinders are within a few % of each other. A common problem with a non powerplate GN is the rear cylinders get more air and lean out much sooner than the others.

Since you're running of an MBC I'd wonder if you have a vacuum leak somewhere. Can you post a pic of your MBC setup? Might need to do a vacuum leak test to see if you have anything big leaking while under boost. Buick GN on this board sells a kit.

 

[cchilly]

Well maybe I will try and get the powerplate on this weekend.

My MBC is an ARO one. Just a plastic air regulator that is plugged into the vacuum line. I will attach a picture of that side of the engine and you can see it somewhat. I don't have any close-ups of it.

I'll also look into doing a vacuum leak test. My buddy is a mechanic, so I can borrow his.

Thanks for the tips and help.

Any special markings I can look for on the turbo so I can tell if it is stock or not?

 

[1chance]

You may have a lose vac line, but be sure to add octain to your gas, that will give you room for error. It will keep knock down. Lead fuel will foul out a stock O2 sensor kinda quick, so get a spare, or two.