PL File Uploaded. Source of Knock?

[HighMileage]

Attached is the PL file of the knock incident I had yesterday. This car has never knocked before.

The file is 547 frames long. The issue starts at frame 395 when I step on it.

As a precaution,I'm going to be pumping the gas out of it,and put my normal Hess super it. Maybe even a splash of 100LL. I'll be taking that slow O2 out,too.

Note: I did a 0-85 blast just 2 days before. No knock then,but with Hess.

Thanks!

 

[garyk1970]

get a 4 bar map so you can monitor boost.

try new gas,new 02.......your on the right track....looks like the knock started in second? looked cold(iat)...engine warm all the way?

 

[HighMileage]

get a 4 bar map so you can monitor boost.

try new gas,new 02.......your on the right track....looks like the knock started in second? looked cold(iat)...engine warm all the way?

Yes,the knock started in 2nd. I eased into the gas while in 1st.

The cold AIT is due to the high-20's temps that day.

As far as the engine warmed all the way.. The coolant temp was above 170'F.

I pumped the gas into my DD and dumped in 5 gal of Hess Super and 1 gal of 100LL. One thing I did notice was a constant steam of b-b sized air bubbles in the clear line I used for the fuel transfer. Today I'll do a test drive.

Something tells me that just putting different gas in would be too easy of a fix.

The 4-bar MAP you mentioned.. That would be used to feed boost info to the PL? Where would I get one of those?

Thanks for the reply.

 

[Boost231]

you dont need a 4bar map. get a 3 bar from any of our vendors on the board.

Cal hartline has them.

this will allow you to log your boost pressure on the powerlogger.

as far as your logs,

your WOT tps is to low. set it to 4.6

MAF looks like crap. its not maxing out so if your running over 14psi might want to change it out.

as far as the knock, looks as if the car is running lean. you getting a one to one raise at the regulator/fuel pressure?

its hard to tune using 02's but your 02's are low.

What chip you running? if the boost is low try addding alittle fuel pressure or add fuel in the chip and see what happens

 

[HighMileage]

you dont need a 4bar map. get a 3 bar from any of our vendors on the board.

Cal hartline has them.

this will allow you to log your boost pressure on the powerlogger.

as far as your logs,

your WOT tps is to low. set it to 4.6

MAF looks like crap. its not maxing out so if your running over 14psi might want to change it out.

as far as the knock, looks as if the car is running lean. you getting a one to one raise at the regulator/fuel pressure?

its hard to tune using 02's but your 02's are low.

What chip you running? if the boost is low try addding alittle fuel pressure or add fuel in the chip and see what happens

To answer some of your questions:

I'm running a Turbo Tweak alky chip. ...with no alky (yet). ...and all factory turbo components.

The low MAF and low wot TPS: I believe I didn't have it completely to the floor,but close. (was nervous about the knock) The last time I adjusted the TPS,I put the wot setting in range.

Low O2's: I read here somewhere that Denso O2's were good. Well,that stupid thing couldn't count it's way out if a paper bag. The old AC Delco one was fast. That will be going back in.

About the fuel pressure... That is in the post following this one.

The 3-bar MAP is on my to-do list now. The only boost gauge I have is the inaccurate factory one.

Thank you for your input.

 

[HighMileage]

Ok,I've only had my GN since July,so I know I'm still a newbie. But,I might have figured this wot pinging situation out. ?

The convenience store gas is out. In is the usual Hess Super along with 1 gal of 100LL. FP set at 43 line off.

Test Drive time: From a stop I gradually step to the floor while in 1st. As soon as I hear boost build,I lose traction,then gain a little. The tranny bangs 2nd,rear tires scream,FP goes over 60psi! ...then very slight knock starts. Not nearly what it was,but there. I immediately let off.

Sounds to me like I'm over-boosting,and that stock 83,000mi pump just can't handle that over-60lb wot situation?

Here is something I noticed when pumping the crap gas out: There was a steady stream of air bubbles in the clear line I used. I used the pump and rails schrader valve to transfer the fuel.

I'll bet it's time to park this thing for the winter,and install the hot-wire kit I bought. ..and get a better pump. Oh,and fix the over-boosting issue and install an alky kit,boost gauge,etc.

Funny,tho... I've never heard this car knock until the other day.

 

[dennisL]

The colder it gets, the more power the turbo makes. You definitely need a "real" boost guage (not the toy LEDs in the factory dash). Easy to hook up too with just a small hose from guage to vacuum block. You can "T" the hose where the factory 2 bar MAP sensor now connects or replace it.

Regardless of whether you get a Power Logger, get a boost guage (0-30 psi).

Dennis

 

[jarredsoon]

tt chip

So as I understand it you are running a TT "alky" chip with out an alky kit installed on the car?? The TT alky chip should not be used without alky, it pulls fuel as it expects alky to be being pumped into the motor. THis results in a lean condition and therefore knock. I would swap out the chip until you get that alky kit installed, not that hard you could do that and a boost guage all in one evening.

Jarred.

 

[TurboDave]

So as I understand it you are running a TT "alky" chip with out an alky kit installed on the car?? The TT alky chip should not be used without alky, it pulls fuel as it expects alky to be being pumped into the motor. THis results in a lean condition and therefore knock. I would swap out the chip until you get that alky kit installed, not that hard you could do that and a boost guage all in one evening.

Jarred.

Plus the fact it has high timing and high boost!!

 

[HighMileage]

The alky will be coming soon. Have to do more research on which system.

For some reason the car ran great with no knock for a few weeks. Then the FP gauge started rising to 60-65psi under wot. Overboosting??

I know for a fact that my 23yr old stock pump almost stops running at that pressure since I heard it moan groan and stop when I had the press too high with a new regulator.
That pump will be removed.

It's now up on jack-stands. Much winter work is starting,including a boost and knock gauge,body cushions,grounds,etc.

Thank you for everyones input.

 

[Boost231]

The alky will be coming soon. Have to do more research on which system.

For some reason the car ran great with no knock for a few weeks. Then the FP gauge started rising to 60-65psi under wot. Overboosting??

I know for a fact that my 23yr old stock pump almost stops running at that pressure since I heard it moan groan and stop when I had the press too high with a new regulator.
That pump will be removed.

It's now up on jack-stands. Much winter work is starting,including a boost and knock gauge,body cushions,grounds,etc.

Thank you for everyones input.

Really don't have to do much research on which alky kit. Razor's kit is the only way to go IMOP.

Also don't run the car hard without alky. If you are running a alky chip run alky. Sorry couldn't type more. I'm using my phone