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TBI MAF code and FAQ

Old 04-19-2008, 11:13 PM
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TBI MAF code and FAQ

Over the coming days, I will be adding info here on the MAF code, as well as whats needed to get the setup going. For starters, included is the TBI MAF code, bin tuning def for tuner pro, and ADS file. Open up the code and have a look through the constants section as well as the XDF to get some idea of whats in there for starters before diving into the conversion. If you have questions (which Im sure people will) please post it and Ill do my best to reply to them all. Also, the ZIP can only be opened in fire fox, not IE.
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$0D_MAF.zip (296.0 KB, 476 views)
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Old 04-20-2008, 02:42 AM
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Re: TBI MAF code and FAQ

I see four files, is any of them suppost to be an xdf file?
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Old 04-20-2008, 10:52 AM
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Re: TBI MAF code and FAQ

yes, one has the XDF extention. Copy the files to a folder or location, and tunerpro should be able to see the file and open it.
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Old 04-20-2008, 01:52 PM
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Re: TBI MAF code and FAQ

Hi Dimented, i want to know if it's the correct pin out
to use in maf mode,
maf pin F12
vss pin F4
vss pin F5
coolinf fan control pin E1
wide band o2 pin B16
iat pin B9

Also I have done a mpfi change in a 1995 Tahoe
by changing a L05 Tbi to a L31 vortec engine,
i've done mod to pcm and jumper in the memcal
but would like to control fan cooling, can i use your
bin without a maf? or do you have a fan control
patche to use in a stock tbi bin?

W/T1500
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Old 04-20-2008, 04:57 PM
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Re: TBI MAF code and FAQ

The VSS is now on pins F2/F3 as not all the PCMs appear to have pins F4/F5 terminated. The TBI MAF code will work with MPFI, but the code is tailored for TBI. The injector firings are locked in TBI mode (memcal no longer controls the firing rate) and all the code is heavily reworked for a wetflow system.

Its possible to patch the stock code with a fan control routine. Probably could use the $0D hack to find some free space (or just risk it and use the end of the program stack), and copy the fan code from the $0D MAF right into a free area of the bin and add a line of code so its executed. I know there was a fan patch floating around here somewhere that someone else wrote.
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Old 04-20-2008, 05:54 PM
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Re: TBI MAF code and FAQ



BTW i opend that folder on my buddies computer before, which is a piece, opened it on mine and saw it, thanks.

Last edited by superbee; 04-20-2008 at 06:00 PM.
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Old 04-20-2008, 07:15 PM
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Re: TBI MAF code and FAQ

Thank you Dimented for the info ,I'am not ready to try maf code right now
but will try it someday.
You're good at code and i know it's not maf code related but can you give
me some info about using air management output to control a fan?I do not understand line 1 L4E7F and line 6 L4E84. Do you think it can be use without
going in the code just by playing with those tables?

W/T1500

* AIR MANAGMENT
***********************************************
L4E7F FCB 2 ; MJR LP o2 SENSOR FILTER COEF 0.8%
L4E80 FCB 192 ; DISABLE AIR INJ IF G.T. 3200 RPM
L4E81 FCB 32 ; DISABLE AIR INJ IF L.T. 22 Kpa
L4E82 FCB 73 ; DISABLE AIR INJ IF L.T. 15 DEG C
L4E83 FCB 0 ; DISABLE AIR INJ IF PWR ENR G.T. 0 SEC'S
L4E84 FCB 135 ; 52.7% LAG FILTER COEF FOR Vss (02A5)FILT MPH
***********************************************
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Old 04-20-2008, 07:18 PM
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Re: TBI MAF code and FAQ

Also, when you get time, can you go through and explain every option you have to change to run a 700, I have an idea but im obviously not getting everything....also what needs to be done to get the tc operative. (tune wise, mine works with some, some it doesnt)

edit- and also, on the wiring aspect. Ive seen several ways people are doing the maf signal wire. ON this tune you posted, does the maf sig take place of another function, like the egr? It seems like i read somewhere somone used the light green wire off the egr solonoid as the maf sig wire, that would prevent having to run a new wire throug the firewall so that would be easiest i guess, the wire that is in f12 on mine is a brown wire, that is just omitted correct? I couldnt find on the wiring diagrams what it was, i assume it was a vss wire and that you need to then take the two vss wires that origionally went to the drac or vssb, and put them into pins f4 and f5?

Last edited by superbee; 04-20-2008 at 09:07 PM.
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Old 04-21-2008, 08:45 AM
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Re: TBI MAF code and FAQ

I think there is a thread that goes over whats needed for the 700-R4. Im going to see if I can dig it up and post a link. There is seperate code that operates the TCC through one of the shift solenoid outputs.

The MAF signal wire goes to the VSS thats currently used for the TOS speed off of the buffer box. The VSS sensor from the transmission must be wired directly to the PCM via pins F2 and F3 (by splicing into the twisted pair from the VSS sensor), which are the TIS inputs. The alternate TOS input on pins F4 and F5 isnt terminated in all PCMs, so I moved it to pins F2 and F3.
----------
Originally Posted by w/t1500 View Post
Thank you Dimented for the info ,I'am not ready to try maf code right now
but will try it someday.
You're good at code and i know it's not maf code related but can you give
me some info about using air management output to control a fan?I do not understand line 1 L4E7F and line 6 L4E84. Do you think it can be use without
going in the code just by playing with those tables?

W/T1500

* AIR MANAGMENT
***********************************************
L4E7F FCB 2 ; MJR LP o2 SENSOR FILTER COEF 0.8%
L4E80 FCB 192 ; DISABLE AIR INJ IF G.T. 3200 RPM
L4E81 FCB 32 ; DISABLE AIR INJ IF L.T. 22 Kpa
L4E82 FCB 73 ; DISABLE AIR INJ IF L.T. 15 DEG C
L4E83 FCB 0 ; DISABLE AIR INJ IF PWR ENR G.T. 0 SEC'S
L4E84 FCB 135 ; 52.7% LAG FILTER COEF FOR Vss (02A5)FILT MPH
***********************************************
The air management isnt the best way to control it, not without code mods. If you start a thread on the DIY-Prom board, I can walk you through what needs to be done. Likely it wont require any coding at all, just applying my fan code as a patch. I also have to check out whats on the air output. I think its by itself, and can be used, but Im not sure. Many of the outputs have multiple functions depending on what the vehicles options are.

Last edited by dimented24x7; 04-21-2008 at 08:49 AM. Reason: Automerged Doublepost
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Old 04-21-2008, 02:20 PM
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Re: TBI MAF code and FAQ

Hi, I am very new to the tuning world and Ive been reading up on it for the past few months, Im building a 355 for my truck and im interested in putting MAF on it. I was wonder what parts i would need to start with MAF, PCM, ect. also what tuning equipment i would need to tune it with. Im running a 700-R4 aswell. Id have to double check what PCM it have its been a while since I crawled under the dash.
also would this code work with EBL.
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Old 04-21-2008, 05:42 PM
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Re: TBI MAF code and FAQ

"a. The 16168625 is the '93 TBI truck PCM.
b. The 16196395 and 16197427 are the '94 TBI truck PCM's
c. The 16197427 and 16156930 are the '95 TBI truck PCM's. The 16197427 is the most popular and has been hacked the most although the differences are slight. This would be the preferred PCM to me although all the ones listed above work."

-Maf, you can use a 5.3 one.
-tuning, lots of options, what im using is an ostrich, from moates.net and you can change the tune as you go which is great, cuts down on time alot.
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Old 04-22-2008, 04:31 PM
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Re: TBI MAF code and FAQ

can a 3 wire MAF be used? i have a pigtail from an S10 and the MAF and IAT are seperate sensors. the colors match up these same so im thinking all would be good. im just not sure if the outputs are the same.
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Old 04-22-2008, 09:57 PM
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Re: TBI MAF code and FAQ

Originally Posted by S105.7 View Post
can a 3 wire MAF be used? i have a pigtail from an S10 and the MAF and IAT are seperate sensors. the colors match up these same so im thinking all would be good. im just not sure if the outputs are the same.
Either the 3 or 5 wire will work. With the 5 wire, you just wire the IAT in the MAF up to the IAT input on the PCM. I think they are a thermister just like the other IATs in use through the years.
----------
Originally Posted by zchevy2 View Post
Hi, I am very new to the tuning world and Ive been reading up on it for the past few months, Im building a 355 for my truck and im interested in putting MAF on it. I was wonder what parts i would need to start with MAF, PCM, ect. also what tuning equipment i would need to tune it with. Im running a 700-R4 aswell. Id have to double check what PCM it have its been a while since I crawled under the dash.
also would this code work with EBL.
The EBL is a custom mask by RBob, and based on the older 6809 while the TBI PCM uses the later M68HC11. Theyre different processors, and the PCM has alot more hardware than the older TBI ECM that EBL is based on. I had a version of it that ran on the older TBI ECMs, but it lacked resolution and the ability to do syncronous MAF reads with the cylinder firings.

Last edited by dimented24x7; 04-22-2008 at 10:01 PM. Reason: Automerged Doublepost
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Old 04-27-2008, 02:01 PM
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Re: TBI MAF code and FAQ

any luck on finding that link
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Old 04-29-2008, 02:23 PM
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Re: TBI MAF code and FAQ

I looked, but didnt find the one specific to the calibration. I'm going to try to get an XDF together for the non-CC TCC controls. The only other special thing that has to be done is to make sure your brake switch is hooked up, or the TCC wont lock. The TCC is controlled internally through the brake switch input. The brakes on/switch off disables the TCC at the hardware level.
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Old 04-29-2008, 06:21 PM
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Re: TBI MAF code and FAQ

I know that, my converter locked with another bin, and this one dont. ill do some playing around when i get the chance.

My maf IS up and running now tho.... Got it tweaked so it will run, just have to get my aldl communication working again so i can tune it.
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Old 05-01-2008, 08:20 AM
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Re: TBI MAF code and FAQ

Theres literally three seperate TCC routines in the PCM. One for the 4L60-E, one for the 4L80-E with PWM'd TCC solenoid, and one for the older trans' with lockup. To get the routine to work, you need to basically set up the TCC routine for the older transmissions with lockup. IIRC, there are no thresholds set, so the TCC remains unlocked. I'll post up a list of the stuff that can be edited for the TCC to give you an idea of whats there.
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Old 05-02-2008, 10:50 PM
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Re: TBI MAF code and FAQ

ok somthing i noticed, i have NO speedo now. It stopped after i tapped into the two twisted wires and put them into the pcm, any ideas on that one?
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Old 05-03-2008, 07:26 AM
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Re: TBI MAF code and FAQ

Originally Posted by superbee View Post
ok somthing i noticed, i have NO speedo now. It stopped after i tapped into the two twisted wires and put them into the pcm, any ideas on that one?
Reverse the wires at F2 and F3.
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Old 05-04-2008, 09:37 PM
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Re: TBI MAF code and FAQ

Like fast said, they need to be reversed. In both the PCM and buffer box, one of the VSS input pins is a ground reference and the other is the signal input. If you have ground to signal and vice/versa, it grounds the sensor out.
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Old 05-04-2008, 09:48 PM
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Re: TBI MAF code and FAQ

Also, courtesy of fast355, here is an additional XDF that has the TCC parameters in it.
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Old 05-04-2008, 09:50 PM
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Re: TBI MAF code and FAQ

Need to use better glue... Heres the attachment
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Old 05-04-2008, 09:51 PM
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Re: TBI MAF code and FAQ

ok great.

btw, how u know the ecm inputs need switched?
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Old 06-01-2008, 09:35 PM
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Re: TBI MAF code and FAQ

Originally Posted by dimented24x7 View Post
The VSS is now on pins F2/F3 as not all the PCMs appear to have pins F4/F5 terminated. The TBI MAF code will work with MPFI, but the code is tailored for TBI. The injector firings are locked in TBI mode (memcal no longer controls the firing rate) and all the code is heavily reworked for a wetflow system.

When you say reworked for wetflow, does the airtemp sensors placement (upstream/downstream from TB) have any bearing on the codes operating characteristics? I have mine in the manifold right under the TB at present, and have been trying to tune in SD with it enabled but might have to go the MAF route beins it's a PITA!

I'm no programmer, and can barely decipher any of this stuff, but was wondering why the need to reroute the MAF signal input and VSS stuff, would it have been more difficult to make the existing MAF bins run the TBI, or pretty much the same either way?
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Old 06-21-2008, 01:13 AM
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Re: TBI MAF code and FAQ

One of the issues is that you need to use a TBI computer to drive the injectors. The TBI injectors are peak and hold, whereas the MAF cars use 8 saturated MPFI injectors. Also, the fuel control stratagy is a bit different for a wetflow system due to the need to compensate for fuel dynamics.

Also, the VSS input needs to be used as these PCMs dont have a dedicated MAF input. The VSS is the only one able to read in a high frequency signal.
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Old 06-22-2008, 10:51 PM
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E1 pin maximum output rating

What's the maximum amp rating for the E1 pin in 427 pcm?
Can it be use to drive two 20/30 amp bosch relays
for my fan setup? Or use one relay to drive two fan relays?

W/T1500
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Old 07-13-2008, 04:59 PM
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Re: E1 pin maximum output rating

Originally Posted by w/t1500 View Post
What's the maximum amp rating for the E1 pin in 427 pcm?
Can it be use to drive two 20/30 amp bosch relays
for my fan setup? Or use one relay to drive two fan relays?

W/T1500
Just an FYI they do make solid state relay's which is just a standard relay only the control circuit used to engage the high load switch is a transistor. Transistors require virtually no amperage to operate. I know a Chevy Trailblazer or GMC Envoy use a solid state relay on the headlights.
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Old 08-05-2008, 01:07 PM
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Re: E1 pin maximum output rating

Originally Posted by w/t1500 View Post
What's the maximum amp rating for the E1 pin in 427 pcm?
Can it be use to drive two 20/30 amp bosch relays
for my fan setup? Or use one relay to drive two fan relays?

W/T1500
The EGR output is probably good for at least 1A or so. Id try to keep it within that range as a max for the load. Otherwise, if using electromechanical relays, you will need a smaller primary relay to drive the holding coils of the larger fan relays.
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Old 09-09-2009, 02:11 AM
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Re: TBI MAF code and FAQ

Interest for this has been slowly but steadily growing, so Im reviving this sticky with some new info. Attached was the latest iteration that I had of the MAF code and tuning/ALDL defs. I will also make up some generic bins with support for manual, standard 700-R4 transmissions, and some 4L60-E transmissions and post those as well.
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Old 09-09-2009, 10:37 PM
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Re: TBI MAF code and FAQ

Originally Posted by dimented24x7 View Post
Interest for this has been slowly but steadily growing, so Im reviving this sticky with some new info. Attached was the latest iteration that I had of the MAF code and tuning/ALDL defs. I will also make up some generic bins with support for manual, standard 700-R4 transmissions, and some 4L60-E transmissions and post those as well.
I have a couple of good bins for a HOT 350 Vortec running around 370 RWHP in both 4L60E and 700r4 flavor hanging around.

Kurt has his truck running Vortec Heads, LT4 Hotcam, and a 4L80E on the MAF Code. So even the 4L80E can be controlled with the MAF Setup. We inverted a shift solenoid in the code.
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Old 09-10-2009, 11:09 PM
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Re: TBI MAF code and FAQ

Originally Posted by Fast355 View Post
I have a couple of good bins for a HOT 350 Vortec running around 370 RWHP in both 4L60E and 700r4 flavor hanging around.

Kurt has his truck running Vortec Heads, LT4 Hotcam, and a 4L80E on the MAF Code. So even the 4L80E can be controlled with the MAF Setup. We inverted a shift solenoid in the code.
How difficult would it be to persuade you to let us eyeball one of those bins, Fast?
I'd like to compare them to what I'm running in my truck, which sounds very similar to his......LT4 HOT cam, Vortec heads, 4L60E, etc.
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Old 09-13-2009, 04:47 AM
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Re: TBI MAF code and FAQ

Originally Posted by Fast355 View Post
I have a couple of good bins for a HOT 350 Vortec running around 370 RWHP in both 4L60E and 700r4 flavor hanging around.

Kurt has his truck running Vortec Heads, LT4 Hotcam, and a 4L80E on the MAF Code. So even the 4L80E can be controlled with the MAF Setup. We inverted a shift solenoid in the code.
Have you had any issues with the TCC? I know some of those had PWM TCCs, which in some ways require the TIS sensor to apply properly, with respect to how the PWM code works. Just curious how they work in an apply/release form.

And if you wouldn't mind, it would help to post up a bin. What you have is probably a lot better than the stock bin that I would generate with the MAF source.
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Old 09-14-2009, 07:22 PM
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Re: TBI MAF code and FAQ

any updates?
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Old 09-18-2009, 01:54 AM
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Re: TBI MAF code and FAQ

Right now its just a matter of finding a good bin to use in general. I can post one of my old bins up with the stuff for the TCC enabled and the correct MAF table added in for the vortec MAF. The only potential drawback is that most of my idle was set for a manual trans, so some retuning might be needed there.
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Old 09-18-2009, 11:35 AM
  #35  
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Re: TBI MAF code and FAQ

Can someone explain to me why I'd want to bother with a MAF at all.
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Old 09-19-2009, 08:32 AM
  #36  
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Re: TBI MAF code and FAQ

With the stock TBI system, the factory intake is fully heated and water jacketed to vaporize the incoming air and heat it to the same temp as the engine. This ensures that the air is always at a uniform temp. But, if you change that by changing intakes and adding cold air, then you start introducing error and the AFRs will drift as the intake charge changes temperature. This can be small, or significant if you use something like an edelbrock airgap intake and CAI.

The reason for this is due to the fact that there is live fuel in the intake. When gasoline enters into the vacuum of the manifold, it flash vaporizes and pulls a good deal of heat with it when it goes to a vapor. The net effect is that it cools down the intake and intake charge, sometimes down to near freezing and below, even in warm weather. This causes error in the fueling if your using SD. The ECM will think that the air in the manifold is at the same temp as the engine, when in fact it could be much colder. The effect is not easily predicted, either. So its hard to correct for. With MAF, it measures the actual airflow, so it doesnt matter what happens in the intake, the fueling will always be correct, winter or summer.
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Old 09-19-2009, 09:39 AM
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Re: TBI MAF code and FAQ

Well you definitely have my attention now. Does this code work with an EBL system?

Could you also more easily run a cam with tighter lobe separation and more overlap? Like the typical 110 LSA?
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Old 09-19-2009, 09:42 AM
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Re: TBI MAF code and FAQ

Just to make sure I am on the same page with you, dimented......at one point the only drawback to using the MAF code was that there was some conflict with using a 4L60-E transmission.
It appears you've found a solution to that now? I was tempted to play with the code and try it on my 1993 K1500, but it has the 4L60E and I like the ability for the PCM to control the transmission. If that is fixed, I'll gladly convert over to MAF and do some testing. I went from the stock '8625 to the '7427 and had issues with the TCC not locking up until I read another thread about the PWM TCC issues.....a switch to a BJLH bin from the BJYM solved that problem for me.
The truck runs good with the Vortec 350, Edelbrock intake, Ultimate TBI modded TB, stock injectors running at 21psi, and ZZ4 cam, but I know there is more there.
Having issues with the tune, as the WBO2 readings get kinda wacky as the engine warms up. Mainly have an issue of a very lean mixture if I increase the throttle more than gradually at highway speeds........that lean POP gets pretty aggravating, ya know?
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Old 09-20-2009, 03:50 AM
  #39  
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Re: TBI MAF code and FAQ

The "conflict" originally arised from the fact that the 7727 does not have all the inputs/outputs that an 8625 has. TX, you may not be happy to hear this, but the 8625 is actually the BETTER of the two. The solution was to simply relocate the VSS signal directly to the transmission input speed input. That input can read teh sinusoidal waveform directly. This frees up the TOS to be used for the MAF. The MAF code has been tested quite a bit. You can run it on a cam with a tight LSA, but you need to be mindful that, even with the injectors phased, some fuel can be pulled out into the exhaust by the scavanging. This can cause low speed hesitation and stumbling when you crack the throttle. Its the same issue that you would have running a TPI computer.

The MAF code essentially works the same way as the MAF portion of the code in the later vortec and LS1 computers. As a matter of fact, I actually modified my vortec PCM to work the same way as the TBI MAF code so that I could get around some of the issues I was having with their blended MAP/MAF fueling logic. This means that there is no tuning needed on the steady state fueling side. The only fuel tuning then comes down to MAP and TPS AE. Im currently running a single pattern isky cam with 221 degrees of duration and a 108 LSA. The car pulls around 10 in of vacuum at idle, but still runs well using MAF.

Also, this will NOT work on the EBL system. The MAF requires a specialized input that can read in and register the pulses from the MAF. I did have a proto-MAF TBI code that ran on my old TBI ECM, and used the core fueling logic from the '165 ECMs along with an analog converter to convert the frequency to a voltage. It worked OK, but suffered from serious resolution issues due to the A/Ds only being 8-bit. The 93 and up PCMs do not have that issue when using the TOS input as its 16-bit and runs at 65536 Hz, so it can read the MAF in with a great deal of precision.

Last edited by dimented24x7; 09-20-2009 at 04:01 AM.
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Old 09-20-2009, 03:57 AM
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Re: TBI MAF code and FAQ

Originally Posted by TXBowTie40 View Post
Having issues with the tune, as the WBO2 readings get kinda wacky as the engine warms up. Mainly have an issue of a very lean mixture if I increase the throttle more than gradually at highway speeds........that lean POP gets pretty aggravating, ya know?
This is precisely why I used MAF with TBI. The MAF code also has an option to allow the AE routines to be driven by the actual manifold temperature. Ive found that the manifold temperature changes greatly with the engine load, and results in the AE demands being variable. I could be driving and suffering from a lean pop. Shut the car off, and restart, and then it would be a rich bog. A real hassle with a standard trans. The solution was to drive the AE temperature compensation directly with a temperature sensor mounted to the manifold plenum. Take a look at the graph below, and you'll get some idea of how the AE changes with manifold temperature. Cold, a large manifold needs everything the injectors can give. Hot, none is needed at all as the fuel cant settle out. On top of this, the manifold temp changes as you drive. When your cruising, the low vacuum allows the fuel to flash and cool down the manifold.
Attached Thumbnails TBI MAF code and FAQ-aemult.gif  
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Old 10-03-2009, 02:07 AM
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Re: TBI MAF code and FAQ

I'm still very interested in seeing one of those bins Fast355 mentioned. I'd like to compare them to what I've come up with and see how close or far off I've gotten with my tuning efforts.
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Old 10-05-2009, 01:44 AM
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Re: TBI MAF code and FAQ

What have you done so far? As long as you have the right MAF table, most of the tuning will be spark and transient fueling, and calibrating the idle. Theres not much else that needs to be tweaked unless your running an auto, in which case you will want to inport your TCC stuff using the 700-R4 XDF posted above. I think I have a thread on here somewhere where I walked Fast through how to make the changes for the TCC if you need a link to it.
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Old 10-05-2009, 10:04 AM
  #43  
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Re: TBI MAF code and FAQ

Third Gen is the only website that exists on the internet where guys are constantly pushing the envelope on TBI and allows readers and all interested parties to constantly be evolving....its amazing....there always seems to be something new coming out of this forum...and the quality of the ideas are so far above what anyone else can come up with on many of these websites...
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Old 02-28-2010, 12:36 AM
  #44  
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Re: TBI MAF code and FAQ

Hi
Anyone working on a TBI w/MAF system lately?

The connector I have for the MAF is similar to the one superbee posted above.
Does this connector Pinout match the Delphi 85mm MAF P/N 15904068 used from 1999-2009???

Pin A on MAF/IAT to Not used, +5V, GND ???
Pin B on MAF/IAT to Pin B9 of the PCM 16197427 IAT
Pin C on MAF to Pin B4 PCM GND
Pin D on MAF to Ignition switched power +
Pin E on MAF to Pin F12 of the PCM MAF signal

Do the pin connections look correct?

Also my ZT-2 Wideband AFR Controller outputs wideband linear or wideband analog which should I connect to Pin B16 of the PCM?

 
Thanks
Mike

Last edited by avst03; 03-01-2010 at 04:57 PM. Reason: Added info
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Old 03-01-2010, 12:52 PM
  #45  
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Re: TBI MAF code and FAQ

Originally Posted by avst03 View Post
Hi
Anyone working on a TBI w/MAF system lately?

The connector I have for the MAF is similar to the one superbee posted above.
Does this connector Pinout match the Delphi 85mm MAF P/N 15904068 used from 1999-2009???

Pin A on MAF to Not used, +5V, GND ???
Pin B on MAF to Pin B9 of the PCM 16197427 IAT
Pin C on MAF to Pin B4 PCM GND
Pin D on MAF to Ignition switched power +
Pin E on MAF to Pin F12 of the PCM MAF signal

Do the pin connections look correct?

Also my ZT-2 Wideband AFR Controller outputs wideband linear or wideband analog which should I connect to Pin B16 of the PCM?

 
Thanks
Mike
It has been forever and a day since I looked at the MAF connector pinout.

The wideband output needs the linear 0-5 volt output wired to B16.
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Old 03-01-2010, 05:08 PM
  #46  
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Re: TBI MAF code and FAQ

Hi Fast355

Did you ever use the IAT that is built into the MAF sensor?

Thanks
Mike
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Old 05-29-2010, 12:38 AM
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Re: TBI MAF code and FAQ

Hi

Does the bin included at the beginning of this the thread contain the MAF tables for the LS truck MAF 2003 5.3L 85mm MAF P/N 15904068 or is there one that suits setup below better.

I would like to run it with my 350 810 TBI heads, stock cam, 55 lb hr injectors and THM400

Thanks
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Old 06-18-2010, 08:07 PM
  #48  
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Re: TBI MAF code and FAQ

Here are some MAF tables for various MAFs. The MAF is pinned to pin F12 for the transmission output speed. If your using a 4L60-E, you will need to directly connect the VSS sensor to the PCM to maintain operation of the transmission.

Let me know if your still interested, and I can help you out some more.
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MAF table.zip (4.7 KB, 102 views)
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Old 07-18-2010, 01:43 AM
  #49  
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Re: TBI MAF code and FAQ

Hi

What should the base timing be set at for the TBI MAF bin?


Thanks
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Old 07-22-2010, 11:55 PM
  #50  
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Re: TBI MAF code and FAQ

Set it to match whats set at your distributer.

BTW, have you had any luck with dialing in the MAF tables?
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