MAFt spike. Has anyone heard of this?

[dsm-onster]

I've been talking on another thread and felt that a new one should be started... Has anyone heard of the maf translator dropping the signal suddenly and drastically at higher airflows? There has been at least one report of this... I am a little concerned because I plan on really pushing my setup this season... Has anyone ever reported a sudden spike in a/f ratios on a pull running a MAFT? If so, was it blowthu or drawthru?

 

[1SloColt]

Go to the bottom of this page for the log: Airflow

 

[DSMcamaro]

This could be my problem.
http://www.dsmtuners.com/forums/showthread.php?t=221621

 

[1SloColt]

This could be my problem.

I doubt it. We are talkin about two totally different things here.

 

[HighPSI TSi Guy]

I've been talking on another thread and felt that a new one should be started... Has anyone heard of the maf translator dropping the signal suddenly and drastically at higher airflows? There has been at least one report of this... I am a little concerned because I plan on really pushing my setup this season... Has anyone ever reported a sudden spike in a/f ratios on a pull running a MAFT? If so, was it blowthu or drawthru?

Yup. started happening to me this season. I have to retorque my head because of it, pushed the head off the block a little last saturday due to that junk. Mine is blow through. however, there are many instances of other people with the problem who have changed all components and still have it.. current theory is that it's some sort of electrical interference, or electrical issue that makes some cars just not work with the MAFT. the grapg 1slocolt is reffering to came from my car.

 

[dsm-onster]

Yup. started happening to me this season. I have to retorque my head because of it, pushed the head off the block a little last saturday due to that junk. Mine is blow through. however, there are many instances of other people with the problem who have changed all components and still have it.. current theory is that it's some sort of electrical interference, or electrical issue that makes some cars just not work with the MAFT. the grapg 1slocolt is reffering to came from my car.

--What was your final horsepower?
--Where did the spike occur on the dyno graph? was it at torque peak? horsepower peak? or elseware?
--This is w/ the latest version of the MAFt, correct?
--Have you tried moving the maf around? or rotating it at least?
--I'm sure you've done this, but is there at least 6" of straight tube just before the maf? What size piping?

 

[dsm-onster]

Go to the bottom of this page for the log: Airflow

Thank you very much! It looks like the airflow (negative) spikes are falling into a curve of their own. . . definately a pattern.

Perhaps this is MAF orientation in the intercooler piping?

 

[1SloColt]

What was your final horsepower? Where did the spike occur on the dyno graph? was it at torque peak? horsepower peak? or elseware? This is w/ the latest version of the MAFt, correct?

He said the car never felt faster, , though we just cleaned up some simple things concerning his charge system, which I think definitely help out his efficiency. I saw it do a 2-3 pull out in front of the shop, it wasn't slow. All I remember from the a/f log was that it was totally inconsistent. I don't think the signal dropage was at any special place throughout the pull from what i remember. Dave, think we should try mounting your translator in a different spot just to see if that does anything? I'd actually like to see if we could diagnose this just to see if we could form a couple of theories.

 

[1SloColt]

Thank you very much! It looks like the airflow (negative) spikes are falling into a curve of their own. . . definately a pattern.

Perhaps this is MAF orientation in the intercooler piping?

I assumed that the reason the signal drop made a curve like that is because the actual airflow curve followed the same pattern, though I could be wrong. His airflow curve would probably be somewhat similar to a graph going through the points at the bottom of those spikes.

 

[HighPSI TSi Guy]

--What was your final horsepower?
--Where did the spike occur on the dyno graph? was it at torque peak? horsepower peak? or elseware?
--This is w/ the latest version of the MAFt, correct?
--Have you tried moving the maf around? or rotating it at least?
--I'm sure you've done this, but is there at least 6" of straight tube just before the maf? What size piping?

It happened mainly in the areas of peak airflow, between 6k and 7k. Latest version of the MAFT. I've tried clocking it differently and it didn't make any difference. There is 6" at least of straight before the MAF. piping is 2.5". It's hard to catch this problem if you don't have a wideband or something with a higher logging resolution than the ALDL logger. The higher resolution you log the more you see what's happening.

I never dynoed it that day, but the previous dyno session it made 475whp/411 torque at 27 PSI.

I am buying a AEM and don't really plan on ####ing with the MAFT any more.