Using TBI on moded 5.7

[Programmer]

Stupid software--message went ahead without me <g>

Can't remember where I left off--had to finish up a transmission job I'm
doing in the shop.

Hope what I said made sense...check your grounds--load them if possible.
Recheck your TPS with
a battery charger "ON" to simulate engine running voltage. Let me know...

Lyndon.
-----Original Message-----
From: Mike Vannorsdel <vannorsdel at rmi.net>
To: gmecm at efi332.eng.ohio-state.edu <gmecm at efi332.eng.ohio-state.edu>
Date: November 8, 1999 2:19 PM
Subject: Re: Using TBI on moded 5.7


>The voltage going to the TPS is 4.5v.  But for some reason at WOT it only
reads
>3.8v.  I'm pulling 20" vacuum.  I didn't reattach the PCV, is this a
problem?
>I'm getting 30 counts on the IAC.  From what I can tell is the TPS is
causing
>the rich idle and the hesitation.  Is there a special way to "autozero" the
TPS
>or just reset all of the sensors?
>
>Programmer wrote:
>
>> Check your engine grounds, and especially those that are sensor related.
The
>> TPS voltage "low" at WOT is a clue.  The TPS is "autozero" type--spec
should
>> be closer to .45 volts. Make sure the throttle plate is at rest when you
>> turn on the ignition. Like Shannon said, make sure the throttle plate is
>> opening fully. The TPS ground is also shared by the MAP sensor--and don't
>> overlook your EGR valve which could be leaking. If you have a scan tool
note
>> the IAC counts. Anything below 25 (and a higher than normal idle) with a
>> fully warmed up engine "indicates" a vacuum leak or wrong PCV valve.
>>
>> Pay close attention to what the BL numbers are doing--they're the self
>> diagnosing parameters you can use to see what the computer is commanding
at
>> the fuel end of things...
>>
>> Lyndon IPTECH
>> -----Original Message-----
>> From: Mike Vannorsdel <vannorsdel at rmi.net>
>> To: gmecm at efi332.eng.ohio-state.edu <gmecm at efi332.eng.ohio-state.edu>
>> Date: November 8, 1999 12:06 AM
>> Subject: Re: Using TBI on moded 5.7
>>
>> >Well the problems I'm facing now is erratic idle and poor throttle
>> response.  I
>> >have tried the timing at 0 and 10 with a little added power at 10 but no
>> fixes
>> >to the problems.  The TBI is used and I'm not sure on the condition of
>> IAC(it
>> >does work but I don't know how well).  The TPS reading at idle is .78v
>> which is
>> >high and at WOT it's 3.8v which is low.  I replaced the TPS and now have
>> added a
>> >hesitation, voltage is the same.  At idle the injectors seem to be
giving
>> way
>> >too much fuel(it almost puddles on the throttle plates).  The MAP is new
>> and
>> >there are no vacuum leaks.  The TPS doesn't seem adjustable.  I'm not
sure
>> if
>> >the problem is TPS, injector, or both.  The engine cruises fine.  I'm
just
>> >looking for smooth running and have faced the fact that I won't be able
to
>> get
>> >max performance from it with the stock ecm.  I have the data on the
engines
>> best
>> >performance level but am unfamiliar with prom programming and don't have
>> the
>> >equipment.
>> >
>> >CSH-HQ wrote:
>> >
>> >> If you really want it right, probably will take a chip (prom).
>> >> Might get by with jacking the timing via the dist/playing with fuel
>> >> pressure, but those are bandaids, but will tell you how far off you
are,
>> to
>> >> a degree.
>> >> Try reading tuning.txt, tuning.doc, and programming 101, then check
back,
>> and
>> >> you'll then have more of an understanding of where you are/what you
have
>> to
>> >> do.  The related material is off of the home page to FTP, and
projects.
>> >> Grumpy
>> >>
>> >> >No relation.  I don't have any reprogramming eqip either.  I'm aware
of
>> the
>> >> >needed settings for timing and fuel with the changes but really have
no
>> way
>> >> >to change the ecm.  I was just looking to see if the TBI at stock
>> settings
>> >> >will be a problem or not.
>> >> >
>> >> >CSH-HQ wrote:
>> >> >
>> >> >> You any relation to Kevin?.
>> >> >> Do you have a prom burner, or related equipment?.
>> >> >> Have you any prom burning experience?.
>> >> >>
>> >> >> More fuel, timing adjustments sound likely.
>> >> >> Have you read programming 101,
>> >> >> do you have a 1227747 ecm?.
>> >> >> Grumpy
>> >> >>
>> >> >> >I have a '91 K1500 with the 5.7 TBI.  I have just rebuilt the
engine
>> and
>> >> >> >made a few changes.  I have raised the compression to 9.5 and
added a
>> >> >> >CompCams XE250(250/260).  What, if any, changes should be made to
the
>> >> >> >timing and TBI to work well with the changes?
>> >> >> >
>> >> >
>> >
>