dshepp806

You got it! Best to you and yours', Rusnak!

Doyle

dshepp806

Well,...well,...not a good evening,..sometimes it seems that those nights will come and send you back to your notes ...tests,..then crawl to this great board...

The car is presently running quite well.....as noted: my problem was intermittent,..but seemingly from the DME relay/connectivity. I decided I'd head out and install the new relay (Porsche 911-618-154-01-OEM,..rx'd today..),..having a close look at the female side of this DME relay connector,...

DME relay detached and sent to the rear footwell for better visual,....sorry guys,..no VOM at this point..I'm kinda' in a hurry.......I first cranked the car (DME relay is the one that's been in there for several months),..let her idle,..all is well...I flex the female connector wires in EVERY direction with no problems,..all connections look good,..there does exist one female side connector that has a larger space between it's opening on the metal ring....I'll have to get a pic.....and ID the (female) pinout......inanycase, it didn't appear to be something that is, or would be, loosing connection........

Tapping,..wrapping,..wire flexing,..nothing would induce ANY problems....

I turned her off,..then loaded the new relay (noting that this relay is rated at 15 Amps and not like the 30 amp ratings of the KAE, BTW,...). I raise my eyebrow,..making a mental note to check the circuit current draw in the schematics....and review my notes on the DME relay,..along with the infamous search button.....still, to be done,...of course,..for now (however):

Loaded the new relay,....no start,..under any circumstances,..not even a remote attempt at starting.....loaded the original: she starts right up. Reloaded the new relay from PP,....no start.

I reconfigure (installing the original relay),..took her out for 40 minutes,..and all is well.....


Now,..on to the investigation....I'll drop this relay in a friend's '88 and see what shakes (tomorrow),..I've a recording session at present,....and no time to indulge the circuit...STILL,..I expected all to "happen" as-planned....but: NO GO! WTF?

Off to make music,..then come back to investigate this "weird" issue.....new relay is bad? SAYWHA?

I'll know more tomorrow,...what a pisser....No time for the meter tonite, gents and Ladies...

AAARRRGGGHHH......


Doyle

dshepp806

BTW,..although no pics,..I can say , upon removing the EXISTING DME relay (the working one)'s cover,..I found a complete "square" in there,..mounted to the circuit board,...poured, ceramic-based, SS device.........

I've yet to open the spare (KAE 3.308.100, 30 amp),..made in Germany, dated 2007,..25th week. I DO know that I removed this relay last year, as I suspected it was causing the similar issue...I just kept it as the spare,..subsequently loading the present DME KAE relay that's been in for about 4-5 months.....and is now (again) a target of suspicion...

Tonight just complicated things...

JAM!

Doyle

rusnak

Well that doesn't sound good.

I wonder if the new one blew? 15 amps is lowwww what is that, around 200 watts max?

dshepp806

Amidst drum tuning,..I'm thinking it to be the case, Rusnak. CLEARLY, I'll have to confirm this via my VOM...but what the hey?...GEEZE,...I'll just order 3 of the KAE's @ $30 a pop for the same price as one Porsche relay that (I think) just failed me?!?!?!?!?!?!??!.........just send this one back,..start over,...stand back a bit?......get some measurements.....I'll know (then) what's going on......back to drums...

Thanx,

Doyle

dshepp806

10:1 says one of the coils are open.....

we'll see.

BEST!

Doyle

rusnak

no bet. I agree that's what you'll find.

whalebird

Sorry for the delay. A little oil on the o ring shepp. NO SILICONE paste. Silicone is death to an O2 sensor in even the smallest amounts and it will pass right thru combustion. NEVER use silicone on any intake connections. If you try to spray carb cleaner, cancel the IACV at the plug, it will compensate for any variations in idle caused by the carb cleaner. BUT with new part in hand, just screw the old one in and count the number of turns to bottom out, then simply screw that bad boy out. Install the new bypass screw to bottom and turn outward the number of turns it took the old one to bottom. From there you will be very close, but you can set the base idle anyways using the jumper method(for IACV).
I hope this small detail nets you good results.
I have an old DME relay in front of me I'm going to look into for my own edification. The link Loren was so nice to provide is my next mouse click after "post reply"
RUSH 2012. Charlotte is just down the road, but who knows...maybe Atlanta? booujzhe seems to have changed the sound of RUSH as I see it. I can't help but hear a little Foo Fighters (whom I am a fan) in some of their latest offerings...the arrangements are powerful and unrelenting like the Foo Fighters. Keep in mind, I'm a listener, not a 'player'.
karoline IS growing like a weed, we just passed the 16mth mark and I wonder where has time gone(?).
I hope Grand-baby is well...keep rocking!

dshepp806

Thanks for the info, Bird.

Do let me know should you be heading to Atlanta for that show (11/1)....I'd love to set up (again) a moment for you to meet the guys (RUSH, that is)!

Grandbaby (Aiden) is doing well...one handsome fellow....I'll shoot you some pics.

I plan to get on the parts installation this w/e...I didn't think about disabling the ICV before introducing carb cleaner.

Got it: light oil ONLY!

Best!

Doyle

dshepp806

Yeap,..I read Loren's provided link long ago,..and just reread it...good stuff. It was from this article that I tended to the vibration transmissions to my DME relay by inserting dampening materials between the relay and car floor.

Hope to find time tonight to research (actually review) the DME "stuff"....I've taken several apart,..repaired a few (for friends),..but have never seen a version that had an encapsulated component approach of the relay(s) that I just looked at,......Even moreso,..I'm interested in reviewing the amperage rating differences in the various DME relays. I recall the Bentley mentioning that the fuel pump current draw test should range between 4-6 Amps. Curious to find out what the other 12 volt buss draws (DME?) through it's contacts (max). For sure: the Porsche relay (+$90) is rated at 15 amps,...for sure: the KAE's that I have are rated at 30 amps.

Are they "adding"?? ((hehe)....I'll find the time to drill down,..soon.

Any data is welcomed...

PP is gonna' take the failed relay back,......I hope to define the failure (through testing) this weekend....what a frikin bummer....

Want to go ahead and ask the far-reaching: As to failure modes of DME relays,..we all are familiar with solder fracturing,..sometimes easily seen under magnification.....Loren's piece on vibrations speak to this....a reflow and all is well.....a relay coil failure (within the DME relay) is quite obvious,..and a hard failure, as the coil needed to pull the contacts in is OPEN and will pass no current,.....HOWEVER:

As to relay contact resistance,..over time....One could (easily) have a condition of VERY resistive relay contacts,..with a good bit of carbon deposit build-up...dropping some degree of the voltage TO the fuel pump, itself. Does anyone know of the "nature" of the fuel pump, as related to supply voltage it sees? That is,...what is the correlation of various supply voltages to fuel pump operation, especially, in terms of "volume" pumped?. Is there a lot of "slack" here?

Work to be done!

BEST!

Doyle

dshepp806

Not to mention I've a brand new fuel pressure gauge test device,..compliments of Len Cummings......SO: we're off to look at fuel pump/system pressures this weekend, as well...

Nice piece from Len,...we went ahead and constructed something that could reach the cabin, should one want to test pressures in a dynamic state (while driving). AGAIN,..only for test purposes.....super-nice gauge,..can't wait to use it....

Not to detract from "DME relay" discussions.....but that fuel pump IS involved!

BEST!

Doyle

dshepp806

Well,..yes,..to detract,..because I know Bird and Rusnak will bail me on the details....and that;s what they need to know (presumedly). Historically (and over a year ago), I had a fuel leak within the are of the fuel pump/piping to tunnel. Luckily, this was fixed without going into the tunnel and replacing hard lines (THAT wasn't the problem). We went ahead and replaced every single thing down there (replacing an original fuel pump,..that was producing spec...) and every other thing we could get to.....all has been well since,.....I'd like to "snapshot" the pump specs (thanks to Len!) ....and quantify that all is well (there).

STILL: I wonder about the fuel pump ops vs. (it's) supply voltages (and DME current draw thru the relay, as well).

BEST!

Doyle

dshepp806

Got a chance to drop the relay into a friend's '88,....relay was a no starter,.....I ohmed the fuel pump relay coil windings,..guess what? Mr. Infinity!!!!! mmmm.....

Done!

Doyle

dshepp806

Bird,...pretty clear, via your omission,..but I would presume one applies NOTHING to the threads of the throttle screw? Dry?

Thanx,

Doyle

dshepp806

Seemingly anti-cathartic,.....I contacted PP about the failed Porsche DME relay,..they are always quick to respond and (even) restitute...I like this. I couldn't (for now) order another Porsche relay at that price (A 15 amp relay, BTW),..SO, in anticipation of an upcoming vacation to Destin, I just ordered 2 of the cheaper relays,...for the next 3-4 thousand miles,..I'll get the Porsche one in (I guess in a few weeks)...off to install the BRAND NEW throttle adjustment screw and fresh O-ring,..reset this base idle.....as mentioned, she hissed at me when I (long ago) tweaked this adjustment, earlier. I plan to disable the ICV (jumper) then apply some carb cleaner (of sorts) to this area,..I'll be sure to "rock" the adjustment screw and see if something raises it's head....otherwise,..she's getting new hardware (the screw, itself) and a fresh o-ring...reset the base idle and see where I'm at.......of course, I'm most interested in getting a fesh O2 on board,..as well as CHECKING the mixture...I've been told that the base idle adjustment does not affect the mixture,..and would welcome the experts' opinions on this.....I know, that in my case,..after touching the base idle screw,..I experienced fluctuations (upon cold cranking) where the system was cycling back and forth between lower and higher revs until she stabilized...I've never seen this on this engine in 5 years,..only when I touched/adjusted the idle screw...SO;

In, the new sheeit goes.....I'm working on getting together with someone who has the proper test equipment to check the mix...I'm tempted to get this piece of instrumentation MYSELF,..then NOT have to call anyone!!!!!!!!!!!!!!

BEST!

Doyle