Update: Tach to 0 on Csi

adawil2002

adawil2002

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A continuation of this thread: http://www.e9coupe.com/forum/showthread.php?t=11397

UPDATE: The Test Run for The Vintage.

Home to Boston/Larz Anderson Cars 'n' Coffee, 2.5 hours, car performed flawlessly earning my 'perfect' status. All highway. Clear cool, sunny. Good to meet fellow forum members.

Larz to VSR, Bow NH. 1.5 hours All highway, car was great for 1.25 hours then stalled 6 miles from the shop. Clear weather warming up considerably. Tach started to surge and bounce yet engine performance was unaffected, then progressed to sudden stall.:twisted:

Following suggestion of removing cleaning fuse panel checking securing connections. Found that the ignition circuit runs through fuse #7 on the coupe.

VSR to home 2.5 hours. Cross lots, 202 to Saco/Biddeford. Clear hot, sunny. Turned the vent window in to cool things off..black jeans and rugby shirt, not good 'summer wear'.
In NH just after a stall, I pulled the back seat, fuel pump relay ground is solid, relay hot like holding a cup of hot coffee, ECU cool.

Engine back fires sometimes on stall, feels like fuel stops and engine runs on fumes and momentum. Takes a few seconds for the red 'L' to come on, then engine is off. Hard starting, like lack of fuel or bad ground.

Stall condition worsens as trip progresses to the point it was happening every 2-3 miles on 295, dangerous and very frustrating. Earning my 'POS' status

So this is time and temperature dependent, no good for a long trip south Time to get the car reliable for the 980 mile trip to 'The Vintage' is this coming Saturday, plenty of time.

Old thought it was fixed post:
Test drove Athena...dried out enough today.

Despite a stall before I left the driveway, restarted and went for broke.

Once warm, she was smooth, powerful, confident and sure footed. Ran flawlessly in all conditions as I tried to cause the 'sudden death'. Fast on and off ramps, hard accel/decel, traffic - for me that's a few traffic lights, washboard back roads, horrible wash board section at a light, spirited sprint on a windy section at 55-60+, sit at idle for 10+ min.

Tested electrical load through out with high & low beams, turn signals, wipers and fan at all speeds, radio with iPod-it's powered with an accessory plug I mounted in the glove box, GPS in lighter, all windows.

Excellent!

Turn on fog lights, a few minutes later car dies, same 'sudden death'!:idea: These lights were not on when the original issue manifested.
Easy enough to re-wire.

Excellent!
 
Found the load shedding relay ground had become loose and barely attached in the plastic plug, the tab locking the female end in the plug broke off some time in the past. Also found the bulb next to the ignition switch had an insulation break and exposed wires.

Cleaned the fuse panel and neatened up the POs wiring rats nest.

Changed the ballast resistor.
 
Iced latte

or McDonald's (litigation) hot? Your relay should not be hot. Lukewarm maybe in Tejas.

1.Your relay is bad.
2. Your pump is on it's last leg.
3. Your fuel filter needs changed.

Number one displays the exact classic symtoms you have. The points inside get dirty or burned and exhibit high voltage drop. ( Heat).

Number two causes number one.

Number three causes numbers two to cause number one.
 
61porsche said:
or McDonald's (litigation) hot? Your relay should not be hot. Lukewarm maybe in Tejas.

1.Your relay is bad.
2. Your pump is on it's last leg.
3. Your fuel filter needs changed.

Number one displays the exact classic symptoms you have. The points inside get dirty or burned and exhibit high voltage drop. ( Heat).

Number two causes number one.

Number three causes numbers two to cause number one.
Click to expand...

Well said.

Of course, you could eliminate the relay as a possible problem by hard wiring the pump directly to a 12V source. If its an original relay, carefully remove the cover and examine the points for pitting and/or burning.

The filters are easy enough to check and/or replace. Blowing through the hoses and filters might indicate restrictions. That includes the filter under the battery platform and the conical screen found in the pump inlet "no 15" below. Examining the fuel pickup is probably not a bad idea; however, in the interests of expediency, as in the case of field repair, might consider possibly backflushing i.e., blowing through the feed to the pump in the direction of the tank to dislodge debris at fuel pickup.

Then there's the pump, that could be failing. The fact that failure does not occur until more than 1 hr seems odd, but not unheard of - especially if the pump is original.

Best of Luck.

23.png
 
If I were driving to the Vintage (wish I was), I'd replace all 3 and take the old pump along for the ride.
 
61porsche & Mmercury,

Thanks, your suggestions are precisely what I was thinking yesterday. It has been a long process of elimination.

In October when the engine was done being rebuilt, all neglected mechanicals fixed in and I got the car home. I cleaned the rusty crud out of the tank, the pick up screen was old yet OK.
Will order a new one.

Was thinking of pulling the tank and scouring with lacquer thinner and a bunch of change to get it spotless.

All fuel rubber fuel lines are new, all in-line filters are new and of course, correctly oriented.

Pump is original, to my knowledge, and has no conical screen, I was shocked, so it has been suspect to me from the start. Fuel pressure is to spec with new regulator. I checked the plug connection today and cleaned old spiders egg sacks from the female side rubber cap. Traced the wires to the ECU looking for any obvious compromises, found none.
Plan to replace with an E28/E24 pump as a stop gap, unless I can get a new original in time.

Will order new fuel pump relay.
 
adawil2002 said:
Pump is original, to my knowledge, and has no conical screen, I was shocked, so it has been suspect to me from the start. Fuel pressure is to spec with new regulator. I checked the plug connection today and cleaned old spiders egg sacks from the female side rubber cap. Traced the wires to the ECU looking for any obvious compromises, found none.
Plan to replace with an E28/E24 pump as a stop gap, unless I can get a new original in time.

Will order new fuel pump relay.
Click to expand...

P61 is right on the money regarding the hot relay. While it is always good practice to have a replacement part handy for suspect parts, it is still possible for you to have an undetected short or poor ground somewhere that is compounding the problem. I am no expert, but since you mentioned having a poor ground at the relay, I still have to wonder about resistance in the wiring or questionable connections. ( I also wonder about the existence of old spider egg sacks and what became of those now very mature spiders. Maybe the shop manual needs to add a chapter on pest control? Or, are you hinting that not only does Batman favor an e9 Batmobile, but Spiderman is an e9 fan too? :lol:)

A hot relay strongly indicates something abnormal, yet an overlooked loose connection especially near the auxiliary air valve can still leave you scratching your head on the side of the road. Same is true with the connections at the manifold pressure sensor. Since leaving either sensor disconnected results in a no-run situation, it stands to reason that a poor connection could result in an intermittent problem brought on by the right combination of heat and/or vibration (and spiders?). Not saying it is probable, just saying it may be possible.

I am hopeful that in your case, the gremlin is the pump or the relay, but no one on this board need be reminded that old cars and old wiring can test anyone's patience - to seemingly biblical proportions.

http://www.e9-driven.com/Public/Library/BMW-E9-Manual/pages/en/61120210.html#refertoc




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New auxiliary air slide valve, modified the air filter with a colored 'ricer' $10 one placed inside the correct aluminum housing, that will not fall out. All electrical plugs pictured above are clean and tight with no exposed wires out of the backs of the plugs.

I have checked and revisited the pictured connections so many times. I've tried removing the spades from the plastic plugs to solder the connections, to no avail, on the throttle position switch and the manifold pressure sensor. These are the only plugs I've found with any visible wires making them suspects.

Thinking of adding a new main relay and fuel injection relay, on the side of the brake booster to the rush order.

Appreciate the humor...wish I had 'spidey senses' for this...although there is evidence of past spider visits, no arachnids or insects have been found.
 
Update: Solved
Main relay looked tarnished and like it had seen better days. It has the same insides as the original fuel pump relay which looked brand new, so we turn the power connection 90 degrees to fit the main relay plug and installed in original main housing. Cleaned all the plug connectors. Replaced fuel pump relay with a new one.

Removed the individual pin connectors from the pressure regulator and throttle position switch one at a time soldering and heat shrinking each. These wire connections looked frayed with broken strands.

Replaced fuel pump with E28.

Condition recurred after 2.5 hours of driving. Was able to get back to service shop during stall condition so tech could diagnose. Stalled on him 6 times in 5 miles, he did not make it out of the parking lot before it stalled.

He replaced the Pertronix 1868 with points and condenser, condition ceased, he test drove for 40+ miles with no stalling. The car does not like Crane Fireball XR700 or Pertronix modules.
 
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