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View Full Version : Thanks for scaring the helll out of me, guys.



Randee of the Redwoods
11-02-2003, 16:37
We should label this episode "Fear Factor". I been keeping up on the fsd,pmd discussion. Incredibly interesting. gmctd seems to have the failures spot on(reading between the lines) with a few other comments showing some "added stress" to the situation. Seems to me the device was built with non-adequate parts(keeps cost down for mass production) with equally inadaquate support equipment(low voltage wire for a high voltage solonoid signal). Again, though, this is all assumption and speculation based on observation by the smart people(I ain't no electronics engineer).
Even the fix seems simple: duplicate the device with more adequate components as well as upgrading the supporting power and signal connections. But what doesn't sit tight with me is the fact that so far(knock on my wooden head) the device in question, operating in my Ebay truck, has so far not given me a problem. But reading post after post after post of failure, failure, failure is really getting me. How long before it's my time?
I looked over my pump one day. I has a bright green tag. I'll assume that means it was replaced at one time. Well, Bill Heath(super great guy) seems to think the noise in my engine is an off timed injector. (It's actually gotton better as of late, but we'll get into that later) So, will my time come? Is failure of the black box immenent and/or a given or is there a chance that it will never fail? Is there a "failure ratio" whereas some devices never fail and some do(crossing fingers hard I'm in the latter)??
Don't get me wrong here. I'm not TOO so bad strung out. I bought this truck full knowing the subject at hand so I will accept whatever outcome the GM engineers have waiting for me.
I am wondering, though, if this device is "recreate-able". Could be a heck of a market if someone was able to build a replacement(hint, hint to the aftermarket).

gmctd
11-02-2003, 19:15
No sure answer for that, Randee.
Mine worked a year and a half after I built it.
Then, towed 3 hours at around 180 deg, no failure.
Temp climbed to around 240deg, towed 3 more hours, no failure.
Towed empty trailer back 6 1/2 hours at normal temps, no failure.
Drove it another week, idling 180deg - sput! Stall- restart.

Put new driver back on the pump, now almost 2 1/2 years later, still running.
Each time I get in it, this little voice in me keeps saying "Heal! Heal, you bowstidge!"
;)
What can I say? Just stick with it, and keep reading the posts.

jd

mhagie
11-02-2003, 19:17
All this chatter about the pmd on the electronic DB4 makes me very glad that my 6.5 is of the DB2-4911 variety.
What does surprise me is that nobody has come along with the better moustrap if you will,instead the devices relocate or insulate the unit from the heat off of the IP.
Here again someone like gmctd probably knows the reason why nobody has attempted a improved version,however if I was to guess (and I am)It would strike me as purely financial, too much engineering,too costly to produce,and not a large enough market to guaranty a decent profit.
To that if I am correct I say BUMMER it is kinda sad that GM had enough years to redesign the system but didn't.
I have been a GM man all of my adult life but I must admit that GM seems to be more profit oriented at the expense of engineering upgrades.
As bad as I hate to say it F$#d has made more engineering upgrades in the last 5-10 yrs than GM.
How many DOHC engines has GM Produced?, mainly the Cad Northstar a good well engineered engine but not exactly a huge seller.
The 3800 has been around for 20 years with very little upgrading.
Even the small block is still a pushrod design,
and the D/Max took a joint venture with Isuzu to develop.
That said I still won't switch. :D ......Merle

gmctd
11-02-2003, 19:32
Forgot to mention - I towed again this summer, same trailer, same load, same distance, same route, same HOT.
But, with improved cooling system (had the dual thermostats, 195deg last time, 185 deg this run), burned the a\c the entire distance, idled the a/c at 185deg several hours up there, temp never got over 210deg towing, mostly 190 - 200.
Coolant temp always dropped when idling.
That was June, still running in November.

Hang in there

jd

charliepeterson
11-02-2003, 19:42
Hey when the Electronics are working correctly you can't beat them. Sure they can give you fitts and you want to pull the hair out of your head when they start going south.

I'll take the "drive by wire" any day over the mechanical way!

turbovair
11-02-2003, 19:56
When it comes to electronic pumps and PMD/FSD failures, its not a matter of "IF", its a matter of "WHEN".There seem to be some pretty smart fellows looking into this PMD/FSD failure situation right now. If these guys can nail it, life as we know it (stalling/dieing) may be over.

kowsoc
11-02-2003, 21:24
Charlie, my thoughts exactly ;)
I don't think you can beat the more accurate timing offered by electronics to give optimal fuel economy, lowered emissions, and response of these engines IMHO. I have my FSD on a cooler for 2 years now without a hiccup. I also know they are not reliable so I carry a used working spare in the glove box....to save a tow.

To my knowledge most of the big rigs are "drive by wire" too.

gmctd
11-03-2003, 04:30
I had plans to redo the OBD-I PCM harness to OBD-II specs and upgrade to the '99 PCM for improved power capabilities. Just one minor thing holding me back - a TECH-II.

I built the truck in 3 weeks - up off the ground 6.2L srw 2wd cc in Oct '99, back down 6.5L TD, drw 4wd cc Oct '99. Took six weeks to do the PCM\engine harness\instrument panel harness, all to get the efficient PCM fuel management.
Still would like to do the OBD-II thing - I do like the distinct sound of injectors under PCM fuel management.

jd

StephenA
11-03-2003, 05:21
Randee- Sorry if all this conjecture has become a cause for concern. Not everyone with the same equipment has the same problems. The original intentions of the engineers designing our trucks were toward optimum performance & reliability, & often they were successful, despite their corporate mandate to stay with in a budget.
For sure, there has been a high rate of FSD failure, but you usually only hear the bad news; folks with no problems have no reason to make as much noise. I'm sure there are lots of success stories, told & untold.
The main cause for concern usually comes from the unknown. Until recently, the threads I have read on FSD problems have addressed solutions based on generalities regarding causes. Thanks to jd & others, we are finally getting some good data on actual causes, so the solutions can be more effective instead of hit & miss.
I have authored or managed many technical R & D projects in my 52 years and have found one over-all rule: the more complicated solutions stem from acting on or trying to solve unknown or undefined causes. The first prerequisite is to actually know what you are dealing with so it can be faced. Black boxes are notorious for creating mysteries and wierd unworkable solutions. Expose the contents and their purposes and things get simple fast.
Not entirely off the topic, my second patent was the wireless in-the-ear monitor systems you see musicians wearing on stage. When I first started, I was just another musician with songs on the radio who also couldn't hear on stage. I had no trouble designing the ear pieces, but the wireless aspect was over my head. I went to Teac, Sony, Phillips, etc. etc. and they all said it couldn't be done. With the help of Stevie Wonder, I hired various engineers, who also ultimately said it couldn't be done. So, I taught myself the tech necessary to the task and began tearing apart wireless gear and exposing the "mysteries". Needless to say, they were just mysteries... -things which could be known. Although my patent has expired, that little episode of confronting and exposing trumped up mysteries kept me in clover for many years.
The FSD module is just another piece of electronics. I am confident jd or Gary Page can come up with a new design, and I am confident I can manage a repair/upgrade for recoverable modules, if I can get my hands on some. So far, no one has contacted me about sending in their failed FSD's, so the problem may not be as severe as I first imagined. Anyway, if my offer is ignored, it's not likely I will run out of things to do for the next hundred years or so. tongue.gif
Hope this helps dispell the fear factor; the time to be scared was actually before these things really began to be confronted... (not to disregard or degrade the many fine efforts by cooler & harness manufacturers, etc, who have obviously improved conditions). smile.gif

[ 11-03-2003, 05:10 AM: Message edited by: StephenA ]

turbovair
11-03-2003, 10:08
StephenA,
I have the info regarding where to send my bad FSD.At this time however, I dont have a bad one to send.The truck is running fine. Ive got a shred of a warranty left. When that expires, Im on my own.I will send any bad FSD's I have to you and I encourage others to do the same.Thanks for the help.

Randee of the Redwoods
11-03-2003, 14:52
That's ok on the general attitude. I didn't mean this post as a finger pointing or rant. I just meant it as a boiling down, if you will. I know the bad news travels faster than good news. But I have yet to see if there is a "failure ratio" of these modules. Doe more have no problems than fail? Do more fail than have no problems? The intermittant "will it fail/will it not fail" sounds like the product of automated assemble line mass production. Just like the 4.6 in my friend Tommy's Tbird. Dropped something while racing. Now it won't run. My girlfriend's 4.6 Tbird, however, has been raced and raced and is just fine.
StephenA, gmctd, and whoever else: if you REALLY want to do this, if you really desire to attempt a replacement box(maybe with the ability to alter fuel and timing like an aftermarket ign for a gasser), I would like to help. It may not be much, but I'll be so bold as to put up some of the financial backing. If there's a glimmer, there's hope.

ucdavis
11-03-2003, 17:36
Randee,
The lifespan of an FSD seems to be like the "average" lifespan of a human, ie: it has a definable number, but the individual experience will vary a lot. If you have a weak ticker, your time will be short; better ticker but maybe weak lungs- still short,... strong everything, long life. Some get 200K on the pump if memories are correct per the posts.
If you have a green-tag pump, that is an early pump, and probably w/the steel rollers (I had a blue tag pump OEM which I believe was the first design, that came B4 the green taggers which had upgrades, that came B4 the no-tag pumps which had still more).
I carry a known good spare FSD always, and when travelling south of the border, I take a spare IP. Usually the IP gives warnings it is wearing out, and frequently the FSD's seem to also. The only really bad part about this trouble (vs the myriad of other lousy parts that break down for vehicles out there) is that it could cause stalling at an unsafe time. But I'd have to say it isn't any horror story compared to some of the faulty design stuff out there (I'm thinking Chevy Vega kinda bad).

Bobbie Martin
11-03-2003, 17:44
I'll have to disagree with you electro pump guys. I'll take a DB2 over the DS4. After spending over 120,000 miles and 7 years with the DS4, I can say I'm glad its gone. I don't have to worry about where the best place to mount the PMD or when the optical sensor will fail. Maybe I'm just a throttle cable kind of guy. Our Mini Cooper has drive by wire and it took BMW months - and many lemon law buybacks - to get the software sorted out. It's still not perfect, but much better than it was. Never had that problem on my SU's!
On another note, we have a Ford dump truck at work with a Cummins and we had to take it to the dealer for some work. I took the driver to pick it up and was chatting with the diesel truck service foreman. There was a Powerstroke Excursion sitting there and I asked him how they ran. His reply "We have a lot of driveability problems with them." I detect a theme here!

StephenA
11-03-2003, 18:48
Hi Randee,
Ranting & boiling down is totally warranted, in my view. After all, the trucks were sold as finished products. My 92 is a honey of a mechanical, but sometimes I wish they had decided to install real headlights...
I am trying to gather data on the failure ratio as well as confirm the causes & fixes. I just need units to test and reports. Mike is sending me my first one which, as jd says, will be revealing.
This is a good ball game in which everyone who wants to can play.
For me, the priority right now is testing & reporting on representative number of units. Would you be willing to test repaired/modified FSDs in your ebay truck? Is your FSD on a cooler or on the pump. If it's on the pump, testing might be tougher...
I wouldn't put $ into it until we have some proven results, which I for one fully expect.
Thanks for the support smile.gif
Turbovair- I hope your FSD runs forever. Thanks to you as well for the support.
Bobbie- I love my 92 too!
:cool:

[ 11-03-2003, 06:07 PM: Message edited by: StephenA ]

Randee of the Redwoods
11-04-2003, 14:41
I'd love to be a test subject, I may have to pass on this for the reason of experience. I have none. My truck is currently stock as it sits(except exhaust) so the black box is on the pump. It really means nothing, but I think for this experiment, you should choose someone who's had fsd problems. Since I have no experience with the problematic issues, the only thing I could tell you whether it works or not. I think it would be more beneficial to you if someone who is familiar with the troubles of the fsd test them as they can more quickly and more precisely detect and diagnose when one is not working right, going bad, or about to go bad. Thanks for the offer, though.
I figure I can start collecting fsd's anyhow if I can. There are some to be had with some shopping around. Me thinks a new pump will be in my near future so buying up some cores for rebuilding won't hurt, I'll just make sure I get the ones with the fsd still attached. I'll let you know when I start snagging them.

Phil Holmen
11-04-2003, 17:20
Randee... I got lucky, I purchased two I-pumps from ebay. I took the FSD off of the first one I got... tested it and it worked... so I thought that pump was probably toast...I put a wrench on it to turn it over... sure enough seized.... so I tore it down out of curiousity. The second pump I removed the fsd... tested it and it was toast.. pump a wrench on... took slight effort but it turned none the less....put the good fsd on the assumed good pump... took it to my stanadyne dealer to be tested... I left it with him for 'bout a month... becasue it would be cheaper if someone else had brought a DS4 that needed testing also due to time to set up bench with injectors and the works.... guess what.... IT TESTED 100%... Now I have a spare I-pump... :D :cool: :D