Low bl's but running lean

[rb68rr]

Here are my scan master readings
Af 6
Lb 32
Int 128
Bl 110
Ats 136
Tps 44
Iac 22
The problem I'm having is at wot the scan master reads in the mid 600 mv. Cruising the bl's are at 117 on a flat road at 65mph. Fuel pressure is 43 psi with line off. Car runs perfect until I go into wot, then it's extremely lean! Fuel pressure goes up 1 lb for every pound of boost as it should. Maf doesn't lock at 255 but does go up to 250. Any suggestions? Thanks Ron.

 

[rb68rr]

This is on my stock 86' T-Type btw!

 

[we4Mateo]

Sounds like a bad MAF as the stock turbo should peg the AF reading even @ 12psi I believe.

 

[rb68rr]

Could it be something as simple as a clogged fuel filter? Haven't changed it in awhile and did run out of gas not to long ago? Maybe picked up some junk from the bottom of the gas tank?

 

[we4Mateo]

Could it be something as simple as a clogged fuel filter? Haven't changed it in awhile and did run out of gas not to long ago? Maybe picked up some junk from the bottom of the gas tank?

Then the BLs would be higher from trying to add the lost fuel and the fuel pressure rise wouldn't show 1:1.

 

[rb68rr]

The bl's lock at 128 during wot so I don't know what they are doing!

 

[earlbrown]

I was thinking it took about 17#s to max out the MAF on a "stock" setup. Running low on gas won't pick up any more trash that usual. The pump always sucks off the bottom no matter how much fuel you have. Now frying the pump from not having the cooling on the other hand....

 

[rb68rr]

I can make it run richer at idle by increasing the fuel pressure but still goes lean at wot! O2's in the high 600's! Any suggestions? Tried a known good Maf with no change! Help! Lol!!!

 

[we4Mateo]

Try another MAF and maybe another translator. The translator's do go bad from time to time.

 

[rb68rr]

I just tried a known good Maf and I don't have a translater! Stock Maf!

 

[we4Mateo]

I just tried a known good Maf and I don't have a translater! Stock Maf!

You need to try a few good known MAFs then. Even one that works on another car may not work right on yours. Did you reset the chip yet and let it relearn? Do you run race gas ever? Check the CC's on the SM and see if you're O2 is lazy. That shouldn't affect your wot fueling though with a TT chip. They lock the BL at 128 @ WOT for consistency and you adjust from there.

BTW, your sig states LT-1 MAF and translator...

 

[rb68rr]

If you read my whole post you'll see I'm talking about my stock T-Type. I've reset the chip and no race gas. Brand new 02 sensor! It's a thrasher chip too!

 

[we4Mateo]

If you read my whole post you'll see I'm talking about my stock T-Type. I've reset the chip and no race gas. Brand new 02 sensor! It's a thrasher chip too!

My bad. Didn't re-read and memory forgotten. Put a TT or Bailey chip in it and try another known good MAF.

 

[rb68rr]

Hard to find good known maf's! Lol!!! I did try a different chip! Don't remember what kind it is but no change!

 

[we4Mateo]

I still bet MAF then. I never trust a stock one. I know it's a stock car but a translator may be in order.

 

[earlbrown]

I cringe when I see 'stock MAF', those things are just so flakey it's just not worth trying to run one. Those things have caused more headaches and running conditions in the last several years than I can count. On the upside they have taught many people that 'new' does NOT equal 'good'.

 

[rb68rr]

I know what you mean! Lol! However if the Maf is good what else am I missing here?

 

[we4Mateo]

You don't know it's good yet...

 

[rb68rr]

It works fine on my other car!