Guy

Need any and all help.......

Before I get started, I read the Watson book, WSM and numerous posts here on Rennlist, hoping for some insight.

This is my second 928 but by first CIS car. Been sitting for 11 years. I drained the fuel, flushed the tank, replaced both fuel pumps, accumulator and filter. Car started immediately and ran great. Ran the car for around 20 minutes, it stalled and died. Was hard to restart but would stumble and try to run. That was about a month ago.

It has been nearly impossible to start since but WAS stumbling as it tried to fire up. Add some starting fluid and it would kick over and die. I removed the WUR and cleaned out the filter screen. It had significant crud build up but was not clogged completely. I haven't been able to get the car to start since, won't even stumble with starting fluid.

Here's what I have checked:
--Has spark at the coil and at the spark plugs
--Has fuel at the injector fittings and at the WUR (I have CIS gauges but haven't ran thru any tests yet)
--Fuel pumps run
--After attempting to start, you can a sound coming from the WUR a slow popping sound every 20 seconds or so, which I assume is the piston rising up and down in the FD
--Pulled and cleaned the spark plugs, they will smell of fuel after starting attempts, not soaked or wet to any great degree.
--I pulled the banjo at the cold start injector and it seemed to have OLD gas still in the fitting.

I am a little perplexed at how well this car ran and how it won't even start now! This has been a learning experience to be sure! I am enjoying myself but my ADHD needs some help in where to focus.

Thanks to all!!!

riq79

I had a very similar problem with my car. It was solved after I discovered that fuel pumps didn't get enough voltage. They did run but not well enough.

AirtekHVAC

Guy, did you remove or replace the micro-strainers in the fuel lines at the distributor? Those were clogged up on mine.....also, the in tank strainer?

LT Texan

I pulled an injector, energized the fuel pump, pressed down on the air valve to confirm the fuel distributor was shot.

No fuel delivered.

Rebuilt FD and good to go.

GlenL

Is the arm stuck down so it's flooding?

SMTCapeCod

Popping in the WUR has my attention. But I'm not having any bright ideas off the bat if you're not noticing fuel loss anywhere outside of it. Wonder if the diaphragm failed..

Running then not- especially since you found debris/detritus in the WUr could mean that more is stuck elsewhere. Key point of occlusion is the brass union where the fuel feed line from the tank goes into the FD, that has a screen that gets blocked.

Sounds like you are getting some fuel flow but perhaps not enough. Pulling the injectors and running them into a container,preferably clear for ease of comparing volume (or a graduated cylinder, if you're really into it) could tell more of the story.

LT Texan

if they squirt gas at all

Guy

Thanks to all.......I am happy to report that the car now RUNS!

Correct! Strainer was cleared BUT I somehow missed a blockage in the line where it enters the FD (at what used to be the fuel screen). It was a big mess of muck, it is now cleared and I believe this was a big part of the problem.

Correct also! I removed each of the lines running to the injectors and blew them out with compressed air. Found two blocked right at the injector union.

In the end, I was getting fuel everywhere it needed to be, just not enough due to blockages. It does not run well of course, I may need to pull injectors as suggested to check for additional flow issues.

You guys are awesome. Thanks to all!!

Guy

Glen, arm moves freely however the car runs 100 times better with the arm depressed ever so slightly down

AirtekHVAC

I replaced my injectors with Mercedes ones, from eBay...think I paid like 64$ for all 8

Guy

Sounds like a plan.......I am likely going to do an intake and vacuum line refresh and will replace then.

My AF adjustment doesn't appear to have any affect whatsover and spins free and loose. I am guessing thats a problem

jpitman2

Load the tank with some Berryman's, and bridge the pump relay for as long as you can stay with it. This should dissolve out some crud all the way through, and deliver it to the filter. Mine was like this when I got it, and everything I touched made it run better and better - plugs, leads, rotor, cap....Get a gauge set (roger), and Watsons Bosch EFI book.
jp 83 Euro S AT 55k

Guy

Thanks. I have put a bottle of b12 in the tank and ran the pump for 20 minutes or so. I also have the Watson book and the gauge set. I am going to keep running it for a some time to see if I can get it to smooth out a little more before I start replacing plugs etc. This is a fun project. I love working on it and appreciate all the help. Thanks

Guy

Just curious. The af adjustment.......am I doing something wrong. it's free spinning with zero resistance. Is this proper?

svpmx83

you will need to push down gently while turning and you should feel it engage the actual adjustment screw in the arm.