Dynamic Airflow dropping to zero randomly. Help

[Proxses]

I'm trying to figure out why the dynamic airlflow would, for a brief instance, drop to zero. Afterwards the car continues on like nothing is wrong. No codes beside the MAF because it is SD tuned on the VVE tables. First I've ever experienced of this. Can't explain it.

Thoughts?

Can be seen in this data log at time: 00:10:06.679
Tune BES 11.hptDrive 02.hpl

Car is a Hennessy TT vette. Upped the boost a bit. Added a boost controller to it. And methanol.

Doesn't make sense to me. I must be missing something.
Hope someone can help. Probably something stupid.

[avido]

any info about the cam? it seems a hell of a air

startup airflow table looks really weird

[Lakegoat]

Did you figure out what it was?

[Proxses]

416cuin engine. Cam is around [email protected] intake, from what I recall. But car was built when it came in. Has this strange condition where the dynamic momentarily drops to zero. Steady state, and two frames at zero, then back to normal. Not worried about startup airflow yet. Just trying to diagnose the hiccup.

I idea what is causing it yet...

[Lakegoat]

I have a little blip sometimes when driving steady on the freeway. I am never scanning when it happens. It dies, then fires up again in a second. ??

[Proxses]

The car never dies. It continues to run. Just a violent hiccup. Happens in boost too, sometimes. Which is REALLY not good.

[avido]

did you try to go in maf only mode and see if you have the same problem?

[bigwillys58]

The car never dies. It continues to run. Just a violent hiccup. Happens in boost too, sometimes. Which is REALLY not good.

my e38 4.8 sierra would do this also with the stock OS in SD. no rhyme or reason as to when it would happen. after boosting the truck and going to the 2 bar OS it hasnt done it since. the only thing i could think was maybe it was an odd hole in the VVE calculations?? i was using the bluecat tool at the time when tuning the VVE.

[Proxses]

I'm gonna try the 2-bar OS. Only thing that suck is that this car runs more the 2-bar worth of boost...
Boost referenced regulator does help though. Should be close.

Surprised few have run into something like this...

[Lakegoat]

Here is mine. Happens at 3:45:49.238. Pretty close to the beginning of the scan. Mine is 2 bar, but a E40 computer.

[Proxses]

Lakegoat, your scan shows that you drop manifold pressure. Mine never changed. All input data streams were solid. Only the calculated airflow dropped off.

[Lakegoat]

I saw that and the dynamic air dropped also. It went from 13 to 5 (or so. I thought that might be what happened on your setup. I have no idea what causes that??? It has been going on for a while. Maybe I should change the MAP sensor.

[Proxses]

If you've got a 2.5bar map, then I'd change it. I've had a couple that go strange like that. Either read at the minimum for an instant, or what really caught my attention is when the read max value while idling. Instantly kills the car.

[Lakegoat]

It is a 2 bar, but I will change it anyway to see if it is defective. Thanks

[R3m0v3r]

Did this solve anything.. I'm having a similar issue with an e38 except my dynamic airflow is maxing out for a few frames then returning to normal.. computer pulls timing and the car feels like I got a wall.. then back to normal.. I'm SD tuned, the maf is connected but not used.

[mycomputeratesme]

I'm trying to figure out why the dynamic airlflow would, for a brief instance, drop to zero. Afterwards the car continues on like nothing is wrong. No codes beside the MAF because it is SD tuned on the VVE tables. First I've ever experienced of this. Can't explain it.

Thoughts?

Can be seen in this data log at time: 00:10:06.679
Tune BES 11.hptDrive 02.hpl

Car is a Hennessy TT vette. Upped the boost a bit. Added a boost controller to it. And methanol.

Doesn't make sense to me. I must be missing something.
Hope someone can help. Probably something stupid.

Having exactly the same issue. Did this ever get resolved?

[Lakegoat]

My issue was a bad connection in the wire splice for the MAP sensor. Soldered all three and not a problem since. I don't know what Proxses did.