Chucks928

Hello,Newbie here. First off let me introduce myself..Chuck here,59yrs old..somewhat a diy type of mechanic ( sometimes thats good,sometimes ,well,not so much! ) But if I do get in over my head I wont let my pride keep me from seeking help. I,ve always had a think for the 928s but never seriously sought one,I was,and still am a muscle car lover who has appreciated the German cars from afar. A few years ago I purchased BMW 5401 Msport and have been hooked on the power and engineering of the German cars! Anywho..long story short,while perusing Craigslist over the summer I kept my eye on a 1982 928...needed tlc..strong runner..blah,blahblah. My curiosity was perked and I emailed for more pics.After looking at the pics I decided he was way overpriced for what it was and kept looking.A few months later he contacted me with a crazy price if I would come take a look. Hmmmm..seems he was way overpriced and being so far away from anywhere was having no luck selling and needed the car gone.Well as you can guess the car is now in my driveway and will be a longterm project. Heres the story. 1982 928. Ljet ..automatic..94000 miles..no winters..but has,from what I can tell,been ridden hard and put away wet. Its all solid and all there and the basic upkeep appears to have been done,but it needs some help. The story was that it had died last year on the way home and his Porsche buddy determined it was a bad alternator.They rigged a spare battery to get it home,and there it has sat. Now this is what I have done and what its doing....jumped car with old battery and alternator..no fire. Gas down the throttle body it fires right up then dies.Brought it home...new alternator,new battery..no fire. Gas down the throttle body it does the same,fires right up but dies. Jumpered the fuel pump relay..pump runs but still the same.My gut says the pump is good,the ignition seems good but a sensor or check valve are not working? Fuel injection is definitely not my specialty but I do have the full set of shop manuals to help.I guess I,m looking for a rough checklist on troubleshooting the car. Like I said,it will be a long term project ,especially with winter just around the corner,but if I have a game plan ahead of time it would be a great help! Any thoughts or questions are definitely appreciated! Thanks!

Randy V

Where are you located - my guess is the land of no paragraphs.



Welcome - read the New Visitor...FAQ sticky.

And, this...

WyattsRide

Gotta love Randy's bluntness!

....THREAD.... (after you're here a while, you'll understand this)

Wisconsin Joe

Welcome. You've come to the right place. All the knowledge you need is here for the asking.

Basic troubleshooting:

Are you getting spark? extra spark plug in a wire or induction timing light will tell you.
Are you getting injector pulse? Noid light will tell you.

From what you posted, I'm going to guess you don't have spark.
First guess on that is the "green wire".

Duh-huh. Re-read it and it fires a bit with gas down the throat. You have spark. Next guess would be fuel not getting all the way to injectors. You can test the pressure. It's pretty simple.

But those are just guesses.

Check for spark and injector pulse, then come back.
Read the "New Visitor" sticky while you are at it.

And, oh yeah...

...IS...

jetson8859

Welcome! Great wealth of information here!


.......WORTHLESS...

Chucks928

Ok...so maybe I should have waited until a later post to see how much I could type without taking a breath..paragraphs were sacrificed...
I will definitely take some time to read through these threads,just thought I should jump in and get started.

I have browsed some of the forums and 928 sites ( 928 OC, 928 specialists and here) to bone up a little on what I,m facing. I enjoy a challenge but not tossing away money needlessly which I hopefully wont have to do!

As far as spark...I think I do have spark,as noted,a little gas down the TB and it fires right up. But knowing these cars can be complex I feel I,ll need some guidance before getting in too deep. The Porsche/BMW shop down the road from me has offered to take a look,but I as said,I enjoy the challenge!
Chuck

soontobered84

Relay, Relay, Relay

Buy a new fuel pump relay, a new fuel injection relay (your current issue), and a new ignition relay.
Install all three.
Start the car.

.......WITHOUT PICTURES!!!!!!

Chucks928

Sooooo..what you,re saying is relays..? That does make sense..I think the fuel pump relay is good,but I,ll start with all three. I,ll tell you,the PO threw in the 6 volume set of 928 shop manuals and they really are informative..and easy for the average mechanic to follow.

Wisconsin Joe

Replace them anyway. It's a simple Bosch 53 relay. Costs about $5.

I think the 82 doesn't have an 'ignition' relay (could be wrong on that).

Having a good diagram of the CE panel (Central Electrical) is a good idea. It's located under the passenger footwell. Lift up the carpet and you will find a plywood panel. Lift that up and you will find all of your fuses and relays.

Diagram here:

https://rennlist.com/forums/928-foru...all-years.html

Helpful hint: When Alan talks about 928 electrical stuff, it's a really good idea to listen to him.

mkriete

Check out 24-21 in the WSM and the pages around it. There is a chart of potential causes for a no start condition and starts and dies. I understand the L-Jet brain is robust, so don't assume it is the issue until you have ruled everything else out. As noted early in the thread, review the new visitor thread.

Don't forget you are dealing with 35 year old wiring and grounds. Find your grounds and make them shine. I find a wire wheel on a Dremel tool works wonders.

Alan

NO! What they are saying is FIRST post some pictures!!

Alan

linderpat

First off, where in WNY are you Chuck? I have family up there, and the great A VanD is there too (in Rochester).
As far as the fuel pump relay, it could be that. Be warned though, the older cars did not use the 5/3 relay for the fuel pump, but a specially dedicated relay that is very expensive as far as relays go. I am not sure when the change occurred - is the 82 a K-jet or L-jet Bosch fuel injected motor? It is still a 4.5 L size, as that did not change in US spec cars until 83.

Also, as someone else already posted, check the pressure. This is critical for early fuel injection systems.

Wisconsin Joe

82 US is an L-Jet. OP actually mentioned that in his first post.

So he has at least some knowledge of what he's got (not ripping on the OP).

soontobered84

Actually, on an '82, the start relay (socket XIV) is a standard 53 relay, but the others are specific relays. The fuel injection relay part number is 928.615.119.00 should be plugged into socket XVI and the fuel pump relay part number is 928.615.113.00 and should be plugged into socket XVII. No other relay will work for the fuel injection/fuel pump for this year model.

And yes +1 on advice that Alan gives regarding your car. He is the resident electron wrangler for this forum and very knowledgeable about the issues presented by these cars.

Wisconsin Joe

Ahhhh. My bad. Sorry.

I'm used to my 85, where all the regular relays are 53s.