Need tuning tips again.

7

707V6BUICKMAN

Member
I figured out my blow back issue, my vacuum leak, I'm still getting knock readings.
I was looking on the instructions for the chip it said my IAC should be 10-30 at idle its 00.
Heres my latest idle readings on scan master.

AF 04
L8 29-30
BAT 13.2
INT 128
BL 136
CLT 168
ATS 75
R 800-825
TPS 42
IAC 00
CC 165
I DONT KNOW HOW TO SEE THESE LAST TWO THEY DONT COME UP
PL
SP
Im getting 11mpg should I change my throttle body because I want better mpg bad didn't realize it would be this bad anyhow on to my tuning problem. when i get on gas easy I get 1.2-1.9 knock reading. when I'm on it & at about 10lbs its 0.0 then as i try to get on it a bit more it starts again.
then on freeway its 0.0 then after 10lbs it starts but i think it might be short fuel it sounds weird like its starving. I've never been over 10lbs i think i should be able to do more with my setup. any help would be great thanks guys.
 
EricM

EricM

Administrator
Staff member
Doesn't look like you have a tuning issue. Probably something mechanical, engine noise, valvetrain, etc, causing the low end knock.

The throttle body has no relationship to MPG.

You might do a compression check, and make sure the torque converter is locking properly when cruising.

Also check fuel pressure under boost to make sure its rising properly.

All your numbers look ok except IAC. You should try adjusting the min air screw on the throttle body (the throttle stop screw). You would want to unscrew it slightly to close up the throttle blade, which should make the IAC open up a little. When done, you might need to readjust the TPS back into the .40-.46 area.
 
7

707V6BUICKMAN

Member
Thanks Eric. What could I change to improve my mpg.
Also you think there is something that the motor shop didn't do right. I seem to see it when I'm getting in it at about half throttle. I don't hear knock. Do you think I should make my alcky kick in sooner. I think there is an adjustment for that. I'm gonna check boost to fuel. For every pound of boost the fuel should rise one pound as well right. I also don't understand how to do compression check on the torque converter.
Thanks so muh anthony
 
EricM

EricM

Administrator
Staff member
Let me clarify.

I meant... Do a compression check.

Also, check to see if your converter is locking up correctly (assuming you have a lockup converter).

I'm suggesting those things as some basic things to check for your low MPG.

On the knock, the low end knock may be false (a noise somewhere). For the knock up in boost, you could test if it's real knock by adding octane. Some people will add race fuel to see if the knock goes away, indicating that it's real knock.

You are correct on the fuel pressure . If the base pressure is 43psi, then at 10psi boost, you should see 53psi fuel pressure on the gauge.
 
7

707V6BUICKMAN

Member
Thanks Eric last i checked my compression was 180. I just had my motor built. how do i check the converter to see if its locking up sorry for so many questions Im new to these things. i also am using Alcohol INJECTION. should i still check using race fuel. i think its my tranny or rear end. I'm going to jack up my car and bang around.
 
EricM

EricM

Administrator
Staff member
The converter will normally lock at 45mph when warmed up. It will feel sort of like another gear, and the rpm's will drop a couple hundred rpm. If you tap the brake while cruising (keep your foot on the gas), it will unlock for a couple seconds and you'll see the rpm's jump up a little.

If it's not locking, mpg will suffer some. If you do a lot of city driving, mpg will suffer. Usually mpg is all about driving habits. RPM also plays a big factor (make sure it's going into 4th gear when cruising).

Mechanical problems could be a stuck injector, or bad fuel pressure regulator diaphragm (sucking fuel through the vac hose). You can check for a stuck injector by turning the key off and see if the fuel pressure rapidly drops to zero.

Also see what the BLM reading is during cruising.
 
7

707V6BUICKMAN

Member
My IAC is 23 when i start my car. I found out why it was at 00 at idle my Vacuum line was off my ball on the bottom of my drive side fender.
My BLM when i start my car after sitting is 146 then as I cruise around it is steady @118 then when i come to a stop its 137 first red light -second red-light 136-third red light 134 then stays until i drive then 118 thats around town.
 
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EricM

EricM

Administrator
Staff member
Now that you have the vacuum line fixed, you should reset the ECM, drive around, and let the BLM's relearn. Then let me know what you have.

Also, can you get the part# on the injector? I need the number on the injector itself. You should be be able to see it on the side of one of the injectors. Might need a flash light.
 
7

707V6BUICKMAN

Member
Ok my injector # is 10D030B
02mil..242-750-816 ect
AF 05 stopped then go's up///stopped let car idle then check 04
L8 34 when stopped the go's up///30
BAT13.4
INT128
BL 138 stopped,cruising 124-125-127-129. as I'm on the gas pretty steady at 125////132 still 124-125 cruising
CLT 160///167
ATS 69 stopped////97
RPM 775-800-825 same
TPS .42
IAC 08 stopped///19
CC 128-167-187-237///96-97-101-103
 
EricM

EricM

Administrator
Staff member
Those numbers look pretty good. Those are the right injectors for the chip.

So, for the knock, just need to figure out if its real knock. If so, then we need to figure out if its going lean.
 
7

707V6BUICKMAN

Member
My motor guy said it seems to be running a little lean. I had my drive line checked its in balance & u-joint good. The rear end is good. Motor was blueprinted and balanced. Today im going to have my transmission looked at to see if the vibration is coming from there.i hope its false knock caused by something i can easily fix
 
7

707V6BUICKMAN

Member
trannys fine just not locking up for some reason its not getting power,but has ground. i think my intake is causing the false knock. I'm thinking of getting a BOV hoping that will help. when it starts sucking hard it starts showing knock.
 
EricM

EricM

Administrator
Staff member
I would look at the O2's as the boost comes up and make sure it's getting over 750mv or more.
Check the fuel pressure with a gauge on a hose, and see if it's rising with boost properly.
Need to make absolutely sure the alky is coming on properly and soon enough.

Your compression of 180 seems high. Was the compression ratio increased?
 
7

707V6BUICKMAN

Member
The fuel was at 60 lbs at 10 lbs of boost. I'll check 02 mv yeah I have a new block I purchased from HWY stars then got new pistons rings cam springs push rods. The compression been that since I received the motor back should they of cut the rings looser
 
EricM

EricM

Administrator
Staff member
If your fuel pressure was 60psi at 10psi of boost, then something is wrong. Your base fuel pressure should be 43psi, with 10psi boost, that's 53psi. If you're really seeing 60psi fuel pressure, then maybe your boost is higher than what your boost gauge says.
Regarding your rings, no, that has nothing to do with it.
 
7

707V6BUICKMAN

Member
I'M gonna send my boost gauge In to it Re- calibrated. What makes my compression high. It's a new block with heads redone & new pistons, rings, valves, valve springs, new cam, bearings, main caps and arp bolts,& blue printed. I floored it earlier & the 02mv were 850 with no knock.then it shifted into 4th and knock started the MV dropped think 750 I got on it a bit more the MV were 832 with knock. i retarded 3 & 4th gear 2degrees and up fuel 10%
I have a 4inch cold air intake that go's down to 3.5. when it starts to such hard i get knock. its really loud I wonder if that can be the cause. I tried to take it out and run the filter off the MAF but it seemed to surge like it wasnt getting enough air, i dknt know if thats normal and i should up my fuel or something..one last thing that has me worried the engine builder said he couldn't get the TA Performance cam to there spec on DOT to DOT it had to be advanced 4 degrees. would this be a problem?
 
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EricM

EricM

Administrator
Staff member
45mph during cruise conditions, when warmed up (at least 150* F coolant).
 
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