Fighting a Lean Condition
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Fighting a Lean Condition
Here's the scenario
HSR, 46psi FP, 28lb/hr injectors, LT1 fuel pump. So I have plenty of fuel
I use Tunerpro for tuning...I've been all over TGO. Guess I'm just not cut out for the tuning thing. But hey I got it! Anyways
WB02 after being warmed up is around 17 and at idle the engine RPM's begin to "surge" between 7 and 900.
I've verfied all my fuel pressure's, WB02 is located in the passenger side header just prior to the collector. No exhaust leaks at the header bolts nor the collector.
Confirmed voltage and ohm reading at the IAT. No Codes either.
Any of you guys have anymore ideas for me?
TIA!
HSR, 46psi FP, 28lb/hr injectors, LT1 fuel pump. So I have plenty of fuel
I use Tunerpro for tuning...I've been all over TGO. Guess I'm just not cut out for the tuning thing. But hey I got it! Anyways
WB02 after being warmed up is around 17 and at idle the engine RPM's begin to "surge" between 7 and 900.
I've verfied all my fuel pressure's, WB02 is located in the passenger side header just prior to the collector. No exhaust leaks at the header bolts nor the collector.
Confirmed voltage and ohm reading at the IAT. No Codes either.
Any of you guys have anymore ideas for me?
TIA!
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
This is a CFI to HSR project.
Dart Heads 165/72
Crane Cam Powermax 2040
D44 3:45's
PeteK stall
There more thats done as well.
One of my questions about the injectors however is that if I'm using the larger injectors wouldn't I be prone to more of a "rich" condition?
The injectors that I'm using are a LT4 injector. What is the pressure that those require?
If its higher than my setting of 46 maybe thats why its lean
Last edited by qws; Mar 7, 2010 at 07:58 PM.
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 551
From: Glenbeulah Wi
Is the car a speed density system? If it is you need to increase your VE table in the idle area, this will add more fuel at idle. Look at the VE numbers at 50 and below KPA and less the 1200 RPM and add at least 15% to the numbers and see if that brings the AFR more in line with 14.7 to 1.
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Yes I am datalogging. My ecm is from dynamicefi, its the EBL/Flash. So its completely tunable. I'm using Tunerpro as well. If anyone wants to look at it for me I'm willing to email it..lol
According to my BLM's is already trying to add fuel. They are up to 150.
Yes its also speed density
According to my BLM's is already trying to add fuel. They are up to 150.
Yes its also speed density
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Yes I am datalogging. My ecm is from dynamicefi, its the EBL/Flash. So its completely tunable. I'm using Tunerpro as well. If anyone wants to look at it for me I'm willing to email it..lol
According to my BLM's is already trying to add fuel. They are up to 150.
Yes its also speed density
According to my BLM's is already trying to add fuel. They are up to 150.
Yes its also speed density
Race Director
Joined: Sep 2003
Posts: 16,836
Likes: 337
From: Database Error Indiana
Have you tried backing down the idle screw and resetting the TPS ? If the throttle blades are open too far the ecm may not be able to compensate. Just pulling ideas out of my hat here.
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Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
I don't think I do. I was under the impression that when the BLM's go higher its dumping fuel in and when lower than the 128 it is restricting fuel. The last time I put a vac gauge on the intake I was getting good vac pressure.
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
I'm pretty sure 150 is the maximum value. The BLM should be hovering around 128. What this tells me is that the learning mode cannot add enough fuel to compensate. If there's no vacuum leak, I'd look at the tune.
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 551
From: Glenbeulah Wi
Yes I am datalogging. My ecm is from dynamicefi, its the EBL/Flash. So its completely tunable. I'm using Tunerpro as well. If anyone wants to look at it for me I'm willing to email it..lol
According to my BLM's is already trying to add fuel. They are up to 150.
Yes its also speed density
According to my BLM's is already trying to add fuel. They are up to 150.
Yes its also speed density
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 551
From: Glenbeulah Wi
My guess would be KPA values of >50 and RPM values of >1200. Make sure you smooth the table so there are no abrupt changes in VE values and then data log the car again.
Drifting
Joined: Apr 1999
Posts: 1,261
Likes: 6
From: Middletown New Jersey
With the factory ECM, BLM max value is 160 on the lean side.
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
I'm making a bit of progress on this problem.
The way my tune program works is depending on what number I use in my BPC-BPC vs Vac table is what determines my A/F from what I'm understanding. So I played around a bit with it today and its getting better.
This is what I did I used in my calculation the Fuel Pressure of 50 which gives me a BPC number of 151. I then went to my fuel pressure and bumped it up to 50. Now my WB02 is giving me better numbers but still needs some more adjustment.
I think I'm bumping my pressure up wrong though. I thought when I adjust it all I do is turn the key switch on and let the pressure come up and adjust through my Kirban Reg. So what happens now is when the car is running my FP is 42 (steady). Can someone verify that when I adjust my FP.... should I be letting the car idle.... then remove vac line and adjust? If this is so I'm willing to bet once I match up that FP with my BPC I should be good to go.
thanks fellas for all your replies!1
The way my tune program works is depending on what number I use in my BPC-BPC vs Vac table is what determines my A/F from what I'm understanding. So I played around a bit with it today and its getting better.
This is what I did I used in my calculation the Fuel Pressure of 50 which gives me a BPC number of 151. I then went to my fuel pressure and bumped it up to 50. Now my WB02 is giving me better numbers but still needs some more adjustment.
I think I'm bumping my pressure up wrong though. I thought when I adjust it all I do is turn the key switch on and let the pressure come up and adjust through my Kirban Reg. So what happens now is when the car is running my FP is 42 (steady). Can someone verify that when I adjust my FP.... should I be letting the car idle.... then remove vac line and adjust? If this is so I'm willing to bet once I match up that FP with my BPC I should be good to go.
thanks fellas for all your replies!1
