89 Suburban Help...no power..jerks on acceleration

In article
.com>,
"Comboverfish" > wrote:

> DJStern, in my short time here you seem to come off as a bit of a
> jackass to just about everyone; legitimate posters, helpers, and the
> occasional dumb-ass who probably deserves it. So since you feed on
> negativity instead of the help others are offering in this otherwise
> good forum, this will be the only time I respond to your asinine
> comments.

I think you need to learn that conversing on usenet is not at all
like conversing in person and with little more to go on than
symbols on a screen, a lot gets lost in the translation.
IOWs, try not to take anything here personal.

> The torque converter will most likely be found in his 700R4 automatic.
> Since I actually know quite a lot about car repair -and- don't waste my
> time attacking every poster who I've deemed to have usurped my
> knowledge, I read John's '4 speed' comment to mean 700R4, the clearly
> most likely 4 speed available for the Suburban. Then I capped it off
> by saying it was just fodder for discussion. Even though a randomly
> engaging TC would cause his symptoms...... Huh.
>
> Some people wouldn't mind spending money on a component that's likely
> to fail soon like a GM ignition module,

GM ignition modules are likely to fail soon?
If the vehicle is likely to leave you stranded, what's the point
of owning it?
Take it a step further, recommend that all the tires be replaced
also since it is possible to get a flat tire when driving.

> when its buried in the back of
> a full sized truck engine compartment in a possibly HIGH mileage
> engine.

For all we know, that ignition module was replaced 18 months ago.
How often should they be replaced to be safe?

> You need to climb on the engine or over the fender to get to
> it. Oh and $50+ means 50 or more dollars, not that the exact brand he
> must get costs exactly $50. Infact there are cheaper crappier ones for
> around $25. Huh.

So, why not say $25+ or even $1+ if according to you, it conveys
the same message?
Then again, since you're advocating replacing the ignition module
because they are "likely" to fail, why even bring up using a
cheap replacement that is probably not even going to last one
month?

> Oh, and they do kinda fail. GM ignition modules across the entire line
> have acted up in so many different ways its unbelievable. You may want
> to note I said "much less probability" than anything else in regards to
> module failure though. Huh.

Yes, GM modules fail, but nothing the OP or you have mentioned so
far suggests that it's a module problem, especially considering
that there are other, cheaper, more likely causes of his problem.

> I agree that a decrease in fuel volume will cause power loss, but the
> way that fuel delivery gets strangled over time by a dirty filter
> wouldn't cause the same pronounced jerking that I got the feeling the
> OP was experiencing. I would classify the symptom caused by a
> momentary insufficient supply of gas due to partial restriction as a
> hesitation or soft dropout. He said the engine sounds as if its
> bogging down which seems to conflict with jerking, so I thought torque
> converter for a brief moment which could cause both. None-the-less,
> jerking symptom usually = secondary ignition. Huh. Usually = in
> general = most of the time. Huh.

"when accelerating or reaching a high rpm."
Could be damn near anything, but a secondary ignition problem
would also show up at lower RPM also.


> Done with you.
>
> aarcuda69062, I know about the distributor shaft / reluctor problem,
> its just that a cracked or 'weak' (as some guys call it) reluctor has a
> reduced field effect and can't trigger the pickup coil at low rpms.
> The usual symptom is stalling near idle speed. They seem to work OK at
> higher rpms where John is having his problems.

Actually, the cracked pole piece is notorious for causing
multiple ignition triggers, loss of dwell schedule and loss of
ignition timing.
Do any of those failures jive with the OPs symptoms?

Or, maybe it's just a bad TPS.
You didn't mention -that- either. Of course the OP won't be
buying a new TPS if that's what's really needed because he's
broke from spending money on an ICM that he didn't need.

>try not to take anything here personal

I'll try. I'll only state my opinion about it this once (more).
Negativity seems so... negative.

>Actually, the cracked pole piece is notorious for causing
>multiple ignition triggers, loss of dwell schedule and loss of
>ignition timing.

In my experience and techs' I talk to as well, it is a major cause of
idle speed stalling from generating too weak of a magnetic field. The
same cracked reluctors work ok above idle. We see different cases
here, apparently : )

>Or, maybe it's just a bad TPS.
>You didn't mention -that- either. Of course the OP won't be
>buying a new TPS if that's what's really needed because he's
>broke from spending money on an ICM that he didn't need

Or maybe its not likely a TPS. Not that in my infinite : ) wisdom
would I have overlooked that, but that it probably wouldn't be a TPS
since the problem doesn't ALSO happen at light load or lower speeds.
If the average weekender was fixing his car he wouldn't worry about
replacing something that doesn't cost much if he new it was a common
problem. He would welcome help in the form of "Its not likely your
problem now, but if you're going to be right there anyway replacing
another high mileage part, consider replacing this one as they are
known to fail. $50 to $100 to replace a 15 year old part? I sincerely
hope that doesn't break your bank. Again, "you may want to consider"
doesn't equal "this IS your problem". Geez.

And finally, "when accelerating" can EVEN mean from a stop. Heavy
engine load assists in creating secondary breakdown. Its common
knowledge. Infact -- you know it, most everyone who even tinkers with
cars knows it, yet I was going through the threads and saw this one...
and noone had mentioned it yet. Hmmm.... Seemed the logical
counterpoint to bring up, all the while never puting down anything
anyone else said or being nasty. That came later : ) Anyway, thanks
for the automotive related discourse,

Toyota MDT in MO

On 1 Jan 2005 23:18:13 -0800, "Comboverfish" >
wrote:

>>try not to take anything here personal
>
>I'll try. I'll only state my opinion about it this once (more).
>Negativity seems so... negative.
>
>>Actually, the cracked pole piece is notorious for causing
>>multiple ignition triggers, loss of dwell schedule and loss of
>>ignition timing.
>
>In my experience and techs' I talk to as well, it is a major cause of
>idle speed stalling from generating too weak of a magnetic field. The
>same cracked reluctors work ok above idle. We see different cases
>here, apparently : )
>
>>Or, maybe it's just a bad TPS.
>>You didn't mention -that- either. Of course the OP won't be
>>buying a new TPS if that's what's really needed because he's
>>broke from spending money on an ICM that he didn't need
>
>Or maybe its not likely a TPS. Not that in my infinite : ) wisdom
>would I have overlooked that, but that it probably wouldn't be a TPS
>since the problem doesn't ALSO happen at light load or lower speeds.
>If the average weekender was fixing his car he wouldn't worry about
>replacing something that doesn't cost much if he new it was a common
>problem. He would welcome help in the form of


> "Its not likely your
>problem now, but if you're going to be right there anyway replacing
>another high mileage part, consider replacing this one as they are
>known to fail. $50 to $100 to replace a 15 year old part? I sincerely
>hope that doesn't break your bank.

Typical Dealer Mentality. OH by the way Mrs. Suckermucker, this here
gizmo is known to fail at about 50K, and you're at 35K. Since it's
only $75, don't you think we should install it?

Goddamn, I just KNEW you never had any grease under your fingernails.
I just goddamn knew it. A customer goes in for a $50 job and comes
out with a $500 bill because of nitwits like you who take advantage of
their gullibility.

> Again, "you may want to consider"
>doesn't equal "this IS your problem". Geez.
>
>And finally, "when accelerating" can EVEN mean from a stop. Heavy
>engine load assists in creating secondary breakdown. Its common
>knowledge. Infact -- you know it, most everyone who even tinkers with
>cars knows it, yet I was going through the threads and saw this one...
>and noone had mentioned it yet. Hmmm.... Seemed the logical
>counterpoint to bring up, all the while never puting down anything
>anyone else said or being nasty. That came later : ) Anyway, thanks
>for the automotive related discourse,
>
>Toyota MDT in MO

In article
. com>,
"Comboverfish" > wrote:

> >try not to take anything here personal
>
> I'll try. I'll only state my opinion about it this once (more).
> Negativity seems so... negative.

There was little if any "negativity" in Dan's post.
He disagreed with your recommendation of shot-gunning an ignition
module on this truck solely for the reason that the distributor
cap was off anyway (so do I). As for your reasoning WRT its
location in the engine compartment, that's life in the big word
of auto repair, climb up, skin a knuckle, get 'er done.

> >Actually, the cracked pole piece is notorious for causing
> >multiple ignition triggers, loss of dwell schedule and loss of
> >ignition timing.
>
> In my experience and techs' I talk to as well, it is a major cause of
> idle speed stalling from generating too weak of a magnetic field. The
> same cracked reluctors work ok above idle. We see different cases
> here, apparently : )

But they don't generate a weak magnetic field as much as they're
responsible for creating multiple triggers due to the fact that a
cracked pole piece magnet has many more north and south poles
than it was originally designed with.
The more common cause of idle stalling on this vehicle is a
torn/sucked in TBI to manifold gasket, you may want to pass that
on to your fellow techs.

> >Or, maybe it's just a bad TPS.
> >You didn't mention -that- either. Of course the OP won't be
> >buying a new TPS if that's what's really needed because he's
> >broke from spending money on an ICM that he didn't need
>
> Or maybe its not likely a TPS. Not that in my infinite : ) wisdom
> would I have overlooked that, but that it probably wouldn't be a TPS
> since the problem doesn't ALSO happen at light load or lower speeds.

At light loads or lower speeds, the wiper in the TPS is usually
in a different spot, so yes, it could very easily be a bad TPS.
I've seen dozens of instances where a cracked resistive substrate
in a TPS caused such a jerking in the engine that you'd have
sworn it was a secondary ignition problem. Also consider that the
ECM uses throttle position to lock and unlock the torque
convertor clutch...

> If the average weekender was fixing his car he wouldn't worry about
> replacing something that doesn't cost much if he new it was a common
> problem.

But it is NOT a common problem.

> He would welcome help in the form of "Its not likely your
> problem now, but if you're going to be right there anyway replacing
> another high mileage part, consider replacing this one as they are
> known to fail. $50 to $100 to replace a 15 year old part?

Every part on that vehicle, -any- vehicle is known to fail.
Using your logic, he should just jack up the body and roll a 2005
chassis and powertrain under it.

> I sincerely
> hope that doesn't break your bank. Again, "you may want to consider"
> doesn't equal "this IS your problem". Geez.

Well, the OP was going after the cause of -one- problem, not
looking for things more germane to what might I replace in order
to improve the reliability of this particular vehicle.
I know that it easy to adopt this approach when one is working in
a dealership and enjoys the protection of no one questioning the
end results and their costs because it's under warranty and it
all gets or can be buried in the shuffle.

> And finally, "when accelerating" can EVEN mean from a stop. Heavy
> engine load assists in creating secondary breakdown.

Yes, it "can EVEN mean from a stop," which starts out as low RPM
and at low RPM the ignition load at WOT is the highest the
secondary ignition system will ever experience from a secondary
dielectric point.
The best way to stress and test a secondary ignition system is
still; cranking the engine at wide open throttle with the fuel
system disabled, this results in maximum cylinder filling which
creates the greatest dielectric inside the spark plug gap.
That's what we taught when I worked for Sun Electric and it's
still being taught by the best trainers in the industry.
Ignition problems tend to most often show up at low RPM high
load, fuel delivery problems tend to most often show up at high
RPM. Not a hard fast rule, but it's a starting point.

> Its common
> knowledge. Infact -- you know it, most everyone who even tinkers with
> cars knows it, yet I was going through the threads and saw this one...
> and noone had mentioned it yet. Hmmm.... Seemed the logical
> counterpoint to bring up, all the while never puting down anything
> anyone else said or being nasty. That came later : )

You weren't put down. Trust me, when Daniel puts someone down,
it's readily apparent!
He also contributes quite generously at a frequency much higher
than 99% of the other regulars.

> Anyway, thanks
> for the automotive related discourse,

My pleasure.

My (friendly) advice if you're going to hang around is to develop
a thicker skin.

On Sun, 1 Jan 2005, Comboverfish wrote:

> DJStern, in my short time here you seem to come off as a bit of a
> jackass

You're welcome to your opinion of me.

> this will be the only time I respond to your asinine comments.

Well, lessee here. My suggestion involved systematic diagnosis and repair.
Your recommendation is that perfectly good parts be replaced just because
they might fail someday. There is quite a bit of asininity here, but it
ain't got my name on it, comboverdude.

> Some people wouldn't mind spending money on a component that's likely
> to fail soon like a GM ignition module, when its buried in the back of
> a full sized truck engine compartment in a possibly HIGH mileage
> engine.

So we drop $100 or so on a component that "possibly" "might" be "likely"
to fail...someday, that's the best antidote you can come up with for what
you perceive as asinine remarks? Fascinating.

> You need to climb on the engine or over the fender to get to it.

I know, I own a truck. Your point is...?

> Oh and $50+ means 50 or more dollars, not that the exact brand he must
> get costs exactly $50. Infact there are cheaper crappier ones for
> around $25.

And you can fill a family-size coffee can with perfectly good modules for
$10 or $20 at any decent self-serve wrecking yard. Your point is...?

> I agree that a decrease in fuel volume will cause power loss, but the
> way that fuel delivery gets strangled over time by a dirty filter
> wouldn't cause the same pronounced jerking that I got the feeling the OP
> was experiencing.

You appear unfamiliar with the phenomenon known as "lean surge", but I can
certainly forgive that since you seem to have a fascinating ability to
experience the exact nature of the symptoms exhibited by a motor
vehicle...simply by reading an e-mail! Fascinating. Tell us, what's the
secret? How's it done?

If you can't take the heat, git outta the kitchen, guy.

-DS

On Sun, 2 Jan 2005, aarcuda69062 wrote:

> Trust me, when Daniel puts someone down, it's readily apparent!


Aw, you're only sayin' that 'cause it's true!

DS

Hi...
I found the filter..the part muber is a 'Ram" G-3727.
It's located about 2 1/2' from the right rear wheel mounted on the inside of
the frame.
There are two nuts, one on each side attached to the fuel line.
Should be easy to take off.
Now, I need to fine the pressure release button/switch..
I checked about near the fuel tank and line. Nothing looking like a valve or
switch..Any ideas where that maybe?
Thanks for the help..John

"Lawrence Glickman" > wrote in message
...
> On Sat, 1 Jan 2005 15:49:00 -0800, "John" > wrote:
>
> >Hi LG..
> >Ok..I'll do some crawling about and see if I can locate it..
> >Thanks again for your help..John
>
> Good luck with this. And a word of caution. Your fuel system is most
> likely pressurized, at least mine is. at about 40 psi.
>
> There is most likely a fuel *shut-off* button/valve in the trunk area
> or there abouts. Do activate that, and expect some spray-out from the
> pressure left in the fuel system. cover your eyes, use a throw-away
> towel or something over the filter before you go about trying to
> remove it.
>
> Lg
>

Hi..
I made a call to a parts store and he said to take out the fuse to the fuel
pump and run the vheicle until it stops. Turn it over a few times and
release the gas cap.
This should release the presure in the line.
Sound ok?
Excuse my ignorance but I am learning as I go.
Learning alot with this truck.
John...


"Lawrence Glickman" > wrote in message
...
> On Sat, 1 Jan 2005 15:49:00 -0800, "John" > wrote:
>
> >Hi LG..
> >Ok..I'll do some crawling about and see if I can locate it..
> >Thanks again for your help..John
>
> Good luck with this. And a word of caution. Your fuel system is most
> likely pressurized, at least mine is. at about 40 psi.
>
> There is most likely a fuel *shut-off* button/valve in the trunk area
> or there abouts. Do activate that, and expect some spray-out from the
> pressure left in the fuel system. cover your eyes, use a throw-away
> towel or something over the filter before you go about trying to
> remove it.
>
> Lg
>

Hi..
I called the dealer and the fuse to the fuel pump is under the marking 'ECM"
I found it in the fuse box on the driver side..
So, according to my info, pull the 'ECM' fuse, pull the gas cap, start the
truck, let it run until out of gas, turn it over a few times, and pull the
fuel filter.
If this sounds wrong, open to any and all comments..
Thanks..John

"John" > wrote in message
...
> Hi..
> I made a call to a parts store and he said to take out the fuse to the
fuel
> pump and run the vheicle until it stops. Turn it over a few times and
> release the gas cap.
> This should release the presure in the line.
> Sound ok?
> Excuse my ignorance but I am learning as I go.
> Learning alot with this truck.
> John...
>
>
> "Lawrence Glickman" > wrote in message
> ...
> > On Sat, 1 Jan 2005 15:49:00 -0800, "John" > wrote:
> >
> > >Hi LG..
> > >Ok..I'll do some crawling about and see if I can locate it..
> > >Thanks again for your help..John
> >
> > Good luck with this. And a word of caution. Your fuel system is most
> > likely pressurized, at least mine is. at about 40 psi.
> >
> > There is most likely a fuel *shut-off* button/valve in the trunk area
> > or there abouts. Do activate that, and expect some spray-out from the
> > pressure left in the fuel system. cover your eyes, use a throw-away
> > towel or something over the filter before you go about trying to
> > remove it.
> >
> > Lg
> >
>
>

The search for ther elusive fuel pump fuse continues...
I called the dealership and the info they gave was pull the ECM
fuse..wrong..vehicle won't start much less use existng fuel to depressurize.
Then I spoke to a mechanic who said there was a 'black box' on the firewall
held on by a 'wing nut' where the fuse is located..wrong again..no such
animal there..nothing remotely appearing to be it..
Then I called a repair shop who said they wanted $50.00 to put it on
(because of a $1.00 fuse I can't find..that needs a $14.00 part..)
I'm beginning to wonder if they design this stuff on purpose.
Or, they designed it and forgot where they put it......
: P
John

"John" > wrote in message
...
> Hi..
> I posted earliar.
> My 89 Suburban, 350 fuel injected, 4 speed loses power when accelerating
or
> reaching a high rpm.
> There is a 'jerking' and the engine sounds as if it is getting bogged
down.
> At idle it sounds good..it only occurs when it accelerates, especially in
1
> and secound gear.
> On the highway you can also feel a 'jerking' motion when accelerating or
> decelerating and lose of power.
> One person suggested I check the catalytic convertor and it checked out ok
> at the muffler shop on a presure test.
> If anyone could give suggestions what else to look at I'd appreciate
> it..John
>
>