Do I need to lower the Alky turn-on point?

[Jerryl]

Reasons for the question;
I get some SERIOUS audible KR if I stomp the throttle.
If eased into the throttle, KR is not as bad. Needles to say, neither of the two are good situations.

If I “pre-spray” the alky by holding the alky test button in for 1-2 seconds, then semi-mash the throttle from 10-30 mph there is minimal or no KR, otherwise it is audible and it scares me. Alky comes in right at 4.5 psi.

I have verified FP @ boost, FP response, 3 MAFS, ECM, TPS 0.44, MPH accuracy, Alky spray, ignition system, plugs 23's@a tight 0.032, IAC 18-20, O2's @WOT .830. Not sure about BLM with this new chip yet.

 

[Blown&Injected]

WOW. I found your post searching for info on alky systems - I do not know much about it but to be able to hear knock is lots of knock and 4.5 psi is nothing for boost - did not think people worried about it until about 14 psi.

Seems like something else is going on. I hear people mentioning EGR when addressing knock issues.

Does the knock go away after the first stomping into it?

 

[Razor]

I would look into power enrichment issues with the chip.

Its like this, your car should not knock if your boost is turned down. If you stomp the pedal and it knocks, then you need to see if its leaning out or has way too much timing. Typically I bet its leaning out.

You can try increasing fuel pressure.. then decreasing fuel amount at WOT.

Carbon buildup could also be a contributor.

Having the alky fix a low end fueling problem is not the correct way to use it. Adding fuel is.

 

[Blown&Injected]

If the knock is coming on low, would increasing the FP help? I thought I read that the computer would compensate for the changes in FP an a actual code change in the injector duty cycle would be needed to add more fuel - or something like that???

 

[Jerryl]

I would look into power enrichment issues with the chip.

Its like this, your car should not knock if your boost is turned down. If you stomp the pedal and it knocks, then you need to see if its leaning out or has way too much timing. Typically I bet its leaning out.

You can try increasing fuel pressure.. then decreasing fuel amount at WOT.

Carbon buildup could also be a contributor.

Having the alky fix a low end fueling problem is not the correct way to use it. Adding fuel is.

Razor,
Agree. During my tuning process, I keep reminding myself that your kits are working successfully on many other similar vehicles at the setting you established. Just had to ask.

Timing is 17 deg, 93 octane, and O2's (based on the s-l-o-w OTC4000) when getting in the throttle are around 0.300. TT upgraded the chip but I did not notice a "stomp the throttle" change. Probably need the PE to come in sooner.

Balanced +0.030, 87 ECM/MAF, 212/212, TA33, PAC, Hotwired Walbro, Electric fans, 160 deg, OTC4000, 2800 10”, TT

I will do some more tuning in a few weeks when I get my trans rebuild.

For the record:
TT has extraordinary CS and is one of the VERY BEST TR chip writers, and, I would not hesitate at all to order a chip again.

 

[Jerryl]

....... Does the knock go away after the first stomping into it?

Well, that is hard to say. It is actually scary to conduct this testing when you get audible KR as soon as you get on the throttle. To answer your question; Knock goes away since I LIFT immediately.

If I ease into the throttle, the car is (to use Razor's terminology)
"Smooth as glass".

 

[Jerryl]

If the knock is coming on low, would increasing the FP help? I thought I read that the computer would compensate for the changes in FP an a actual code change in the injector duty cycle would be needed to add more fuel - or something like that???

True, the PE (Power Enrichment) mode will take care of that, but that is a function of the program in the chip.
I did increase the FP up to 48 at one time and BLM's dropped to 112.
While I quit chasing the magic 128, there were still KR issues and I think it was too rich at that setting effecting spool up.

This is where DS is superior. With a few DS logs, the chip would be pretty much exact for my combo.

 

[Razor]

How bout something else like fuel pressure regulator not increasing lb per lb?

Or an EGR valve opening under boost creating a lean condition?

Or an issue with the TPS not reading properly and letting the ecm know its changing.like a dead spot on it.

These things are hard to figure out with a slow scantool.

Eric's chips are not the issue. And adding PE trying to cure another condition is not the correct way either.. Typically when you get on the gas, the o2's should jump into the 800's.. typically.

Disconnect the hose to the egr.. check its gasket for leaks.. and check your FPR..

HTH

 

[1 RARE T]

How about a leaking boost sensing line to the controller?

Ask me how I know it can happen.

 

[Jerryl]

How bout something else like fuel pressure regulator not increasing lb per lb?

Or an EGR valve opening under boost creating a lean condition?

Or an issue with the TPS not reading properly and letting the ecm know its changing.like a dead spot on it.

These things are hard to figure out with a slow scantool.

Eric's chips are not the issue. And adding PE trying to cure another condition is not the correct way either.. Typically when you get on the gas, the o2's should jump into the 800's.. typically.

Disconnect the hose to the egr.. check its gasket for leaks.. and check your FPR..

HTH

Razor,
FP increase lb for lb. No issues there.
I will disconnect and plug the EGR (although disabled in the chip)
I keep forgetting about the EGR.

TPS is new and has been replaced and verified.
Max is 4.72 as well.

Understand Eric's chip are not the issue.
Did not mean to imply that at all. My apologies if it "sounded" like that.

 

[Jerryl]

How about a leaking boost sensing line to the controller?
Ask me how I know it can happen.

These have all been verified and 100% zip tied. The car has "gas compatible hose" so, cracks/rips are not likely.
Good thought though.

 

[vacuum 6]

What about increasing the alky ramp a bit...maybe alky not ramping up fast enough.

I had the some type of issue. I increased the ramp a bit and when I say a bit a mean very little and verified per a gauge that the alky psi came up fast enough.

 

[Kevin87TurboT]

I had to ramp up my alky turn-on point pretty good to stave off detonation as well. I had also had to turn down the timing at the 2500-4000 rpm range as well...that was easily accommated by the XFI system.
Kevin

 

[Razor]

At 10 PSI boost.. the car should not knock or need alky. In other words.. low boost the car should pass this test with flying colors.

If it does.. then we can screw around with the alky settings and make the system more aggressive.

First paragraph first

 

[Jerryl]

At 10 PSI boost.. the car should not knock or need alky. In other words.. low boost the car should pass this test with flying colors.

If it does.. then we can screw around with the alky settings and make the system more aggressive.

First paragraph first

Understand.
Do I turn the alky off and tune for 10 PSI with an alky chip? ......... Or ....
Do I get another non-alky chip, tune for 10 PSI and then get the alky chip and finish the tune with alky?

Maybe I need to find out if the chip is set below 10 PSI for alky suppliment.
Otherwise, it will run rich and could get rich KR????

 

[Razor]

At 10 PSI you can do either. Run with or without the alky. We need a baseline at low boost.

The amount of alky at 10 PSI is negligible. I suggested tuning without to eliminate added things to be looking at. All street chips alky or not will work the same way at low boost.

 

[Jerryl]

At 10 PSI you can do either. Run with or without the alky. We need a baseline at low boost.

The amount of alky at 10 PSI is negligible. I suggested tuning without to eliminate added things to be looking at. All street chips alky or not will work the same way at low boost.

Thanks all. I really appreciate the feedback.
I will give an update after I get the car running again in a few weeks

 

[Jerryl]

Got the car running again. Never touched the alky settings.

Lowered the timing 3 degrees on the 17 degree TT chip and all is fine.
Found that the actual timing was off around +3 degrees. Timing light indicates a current 15-16 degree actual. Zero KR 18 PSI. :biggrin:

Posting the results and final resolution in the hope this helps someone.

 

[JDSfastGN]

good to hear jerryl, i used the new laptop finally this weekend and got it all setup for running DS. This weekend won't work for me but if sometime next week u want to meet up and hook it up and see if we can get a little more out of it pm me.

 

[Jerryl]

Well, I feel dumb.
I am getting to know this car pretty good though. :tongue:
I may have lowered the timing to cover up other problems.
Back to SQUARE 1!
Time to increase fuel pressure (like I was told) and not worry about BLM for now (?) I will get this thing figured out yet someday.

JDEstill, I am ready when you are.