911 Question......Doc?

[Steve]

My brother has an '86, with a no-start condition. Engine spins freely on the starter, and he said that it fired briefly, sputtered, then died and it hasn't wanted to start since. I am thinking fuel pump, isn't it supposed to be "iffy"? In any event I think it's fuel-related. Any suggestions?

 

[GB1]

Doc?

He's making house calls.

He will know, but I am kinda on your page here. I am sure that when the Doc is in he will be able to tell you a few things of interest.

Patrick

 

[sammyb]

I know more about the earlier 911s (having owned a 70 911T.)

Fuel pump is a likely source. I would also assume that if the '86 still uses the Bosch CI ignition system, there might either be a bad connection or the system finally fried. (I had to replace mine.)

So I've narrowed it down to: no fuel or no spark. (I'm so dang helpful! /ubbthreads/images/graemlins/wink.gif )

 

[Steve]

Sammy, you're a regular guru! Thanks /ubbthreads/images/graemlins/grin.gif

 

[DrEntropy]

Geez... I go away for a while and durned if it don't look as if I'm AWOL!!!

'86 911? I seem to recall they went to EFI about then. Fuel pressures is the first thing to check if you know you have spark. 36~38 PSI at the rail should be right. Check for a trigger pulse at the injectors next. Trigger voltage is lower than 12V so an analog VOM set to read 10V will "flutter" if the trigger pulse is there.

HTH

Sorry it was so late.

 

[Steve]

Thanks Doc.....looking more like there's no spark. He squirted a little starter fluid in through the air cleaner, not even a splutter from it.

 

[DrEntropy]

eeep.

Bit more problematic: that thing has relays on its relays. Have you a schematic? If not, I'd suggest hunting down the factory ones. Initially more dollars but REALLY the best info, IYSWIM. Have you put a timing light on a plugwire to see if there's a pulse?

BTW, is it EFI or CIS?

 

[Steve]

Need to check.....it's me bro's car, I don't get to see it very often.

 

[Mickey Richaud]

[ QUOTE ]
BTW, is it EFI or CIS?

[/ QUOTE ]

Neither... It appears that it's DOA. /ubbthreads/images/graemlins/devilgrin.gif

Mickey

 

[Steve]

Rimshot please...... /ubbthreads/images/graemlins/grin.gif

 

[Steve]

I told him......buy an LBC. But nooooooooo, he couldn't do that. In his opinion old cars are unreliable and you can't get parts. So what does he go and do? The Porsche has been most unreliable, and my MGB keeps on running, never misses a beat. He has now spent more than the purchase price of my MG in getting the Porsche up to par, and it still isn't. My S-I-L now refers to it as "that money pit".

Hmmmmmmmmmmmmmmmmmmm.

 

[DrEntropy]

heeheee... Just another bit of evidence that the Germans didn't *really* loose the war. /ubbthreads/images/graemlins/jester.gif They're getting over by cleaning our wallets, one Porsche owner at a time! /ubbthreads/images/graemlins/grin.gif

 

[Steve]

[ QUOTE ]
heeheee... Just another bit of evidence that the Germans didn't *really* loose the war. /ubbthreads/images/graemlins/jester.gif They're getting over by cleaning our wallets, one Porsche owner at a time! /ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]

Amen to that, brother. /ubbthreads/images/graemlins/crazyeyes.gif

 

[swift6]

Many Europeans that I have spoken to now see the EU as Germany finally conquering Europe as well, this time it's financial and not physical. And that they are using France as their mouth piece to distract people from the fact.

/ubbthreads/images/graemlins/cheers.gif

 

[Steve]

As a matter of interest, the problem turned out to be the ME Control Unit. $1,300 installed, for a second-hand unit! Makes LBCs all the more attractive, doesn't it?

 

[jackq]

I have two 911s...they sit more than move. My 70E model is stored..my choice..but the 75S has me stumped. All of the sudden it started acting strange by shooting loads of fuel as soon as you twist the key....and I mean loads of fuel. Changed the fuel dist...twice..same problem. Tinkered with it but finally admitted defeat. Car is beautiful but may start prting it out rather than let it sit....any thoughts???

 

[Steve]

It doesn't have one of those ME units does it? My brother's '86 was occasionally hard-starting, and then refused to start totally. These things, apparently, control the amount of fuel that gets delivered. They do tend to go on the fritz. If yours has one, it may be over-active. Just a thought, for what it's worth.

 

[DrEntropy]

As long as it has that "Stuttgart" badge on the nose, it'll be long dollars for repairing it. Most of them are NOT owned by DIY'ers... rather by folk who have pink places under their fingernails. It also takes a brace of analyzing equipment and computers to do much of anything to the newer ones, which kinda "keeps the riff-raff out" IYSWIM.

Last engine I did was a year or so ago, 930 Turbo. CIS, lots of time/patience/energy. I'll stick with my yestertech LBC's for personal use. Reliable as a house-brick. /ubbthreads/images/graemlins/grin.gif

 

[jackq]

The 75s is the CIS...when you turn the key...not to start..jsut to ignition...it frigging screams and gas pours out. I've done all the work on my 70E(dual webers) done all the tensioner upgrades on both cars..replaced the blown 2.7 in the 75s a couple of years ago...all was fine. then this. I'm currently on the hunt for a 3.0 0r 3.2 for an upgrade. If I do, it'll mean I have to put off buying a plane for a year or so. I've been planeless for a while now and starting to fidget.

 

[DrEntropy]

Jack, That CIS problem still has me going to the fuel distributor/airflow plate/arm adjustment. The only way I know of for the fuel to be allowed to run like that is for the arm to be in the "demand" position in relation to the fuel distributor head. Otherwise the center piston in the distributor head should be "blocking" fuel flow. Certainly wish we lived closer to one-another.