vorstellung 450sl from California 1979 with TSZ-4

Hi Volker,
Success, I bypassed the fuel pump relay, drove 16 km the first day on city streets. I then secured the hood to prevent it from flying open, the only way to see the fuel pressure is to have the gauge being held with a large magnet on the fender and a piece of inner tube between the magnet and the fender paint!

Then I went for 45 km without hesitation even on our steep uphill freeways... going 110km (speed limit almost observed), fuel pressure steady at 50psi...

Now I have to find the culprit, on either the fuel pump relay or the ignition relay circuit -the one under the fuel pump relay- that I removed after the failed test in April.

Thank you for your suggestions, will post progress as it is always good to convey our findings, failure or success.

Best,

Michel

P.S: now I have to figure out why the E32 has high Nox! No code founds, I need to get a copy of INPA 3.0

It never stops, I repeated the fun ride... at some point... hesitation in a turn... but there is still plenty of power with a bit a rich exhaust ... then engine quits and smell of gas.... that was an easy one, fuel hose from fuel filter to accumulator cracked, at least we did not have to call the fire department...
Cheers
Michel

Hi Michel,
On a model year 1980 you already have a ECU type fuel pump relais. They are known to fail with cracks on slder points of relais.

Here is a long awaited update... finally after replacing the fuel pump, the fuel pressure were up to specs... did a few test rides and today being a nice day, we drove to the the test station, and failed on a leaky gas cap, off to the next car parts place which had the gas cap  and passed all the tests

Here are the results:

Hi Michel,

it is good that you have sorted things out after such a long time. Have fun with your car !