RPM'S dropping when peddel steady....

[Rally Smith]

What's a PWB?

Sorry, PBW.

Injector Pulse Band Width.

[EagleMark]

Sorry, PBW.

Injector Pulse Band Width.

Nope try again...

I think you've been reading about the BPW (Base Pulse Width) or BPC (Base Pulse Constant)? Not to be confused with Async and Scync BPW limits. Your truck is $0D right? It's handled a little different under Engine Constants, Injector Flow Rate and Cylinder Volume. If your fuel pressure and injector size is same as stock then they would not need to be changed.

[Rally Smith]

Yes it's a $OD. My fuel injectors are stock but the fuel pressure has been bumped up to 15psi.

[EagleMark]

I'd start with new actual reading by using the injector size spreadsheet and set "Injector Flow Rate (TBI lb/hr)" Don't think you'll need more fuel then VE will supply so may as well set it properly.

65.52 pph

[Rally Smith]

O.k. thanks Mark.
I will get to data logging and adjusting the VE Table now.

[Rally Smith]

Hey Mark, on the excel file you attached, I have a question... Under the BPW Calculation, where does that number plug into? I was thinking the Injector Offset vs. Battery Voltage under the Tables tab in the parameter tree but not sure.

Thanks,

Rick

[EagleMark]

Scalers, Fuel, Base Pulse Width.

[Rally Smith]

Thank you Sir.

[Rally Smith]

Ok, I have checked 3 times and I do not see anywhere in the Parameter Tree a Title called FUEL. I have looked through all of them and nowhere do I see where it says BPW. Is it BPW vs. ? or something? I'm running $OD & TPV5_v250.xdf if that matters or helps. Sorry to keep asking this question.

[gregs78cam]

If you are using 93V8S10's Advanced .xdf then you should have a section with 6 or 8 injector flow entries, along with number of cylinders and maybe displacement. open the TBI LB/HR one and input injector flow.

[EagleMark]

Sorry Ralley Smith! I still think you have a differant ECM. Greg has you going right for yours!

[Rally Smith]

If you are using 93V8S10's Advanced .xdf then you should have a section with 6 or 8 injector flow entries, along with number of cylinders and maybe displacement. open the TBI LB/HR one and input injector flow.

Did that.

So I should be good there then.

Off for more data logging.

Thanks guys I appreciate your help and patience,

[Rally Smith]

O.k. I finally got a new MAP Sensor and still have the hesitation problems while idling. I can take the map hose off and suck air and Idle stabilizes. This is driving me crazy, any ideas guys?

[jameslleary]

O.k. I finally got a new MAP Sensor and still have the hesitation problems while idling. I can take the map hose off and suck air and Idle stabilizes. This is driving me crazy, any ideas guys?

Whats the MAP reading at Idle on a DL?
Lower the fuel pressure? 15 seems kinda up in the clouds for an otherwise stock engine.
Manifold leaks?
Take the PCV valve out, plug the port in the valve cover with a cork or shop rag, and hook a propane source up to the breather tube with the engine at operating temp, crank open the propane, and check for under manifold intake leak.
Just had this similar problem on a 94 silvarado...and that was the problem. It was soo bad, that the vacuum at Idle was down in the neighborhood of 15"
Other than that...Timing chain? Probably not possible to stretch enough to mess vac up, but one thing to rule out anyways.
MAP port on the throttle body clogged?
Ummmmm.....

[EagleMark]

Vacuum reading or MAP reading?