Using TBI on moded 5.7

[Programmer]

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?
>> >> >
>> >
>