View Full Version : A prize will be given
I ran my car at go kart stage for 10 miles or so last fall, 3rd gear 65 mph or so. Spent the winter putting on the body. Took it out and it ran rough at first. It smoothed out so I took it up to 4000 rpm in third. Boy that feels fast that close to the ground. It coasted to a stop, would not restart so I towed it home. Cranked fine, no start. Disconnected the fuel hose and stuck it in a 2 liter bottle, cranked for 10 seconds and got a liter. I then I disconnected the ground terminal from the battery for 5 minutes and tried again. It started immediately and ran fine. I had a preliminary tune last fall. A mechanic friend wants to do a smoke test next.
Take a guess. I will try whatever you suggest. Whom ever comes closest wins the prize.
DSR-3
05-05-2020, 12:51 AM
Crank position sensor failure or it's connector came off?
The only "failure" I've had with my 818 was my not fully latching the connector, and lights-out when I hit a freeway joint. Scary in 4 lanes of traffic!
Good luck!
Bob_n_Cincy
05-05-2020, 01:38 AM
I ran my car at go kart stage for 10 miles or so last fall, 3rd gear 65 mph or so. Spent the winter putting on the body. Took it out and it ran rough at first. It smoothed out so I took it up to 4000 rpm in third. Boy that feels fast that close to the ground. It coasted to a stop, would not restart so I towed it home. Cranked fine, no start. Disconnected the fuel hose and stuck it in a 2 liter bottle, cranked for 10 seconds and got a liter. I then I disconnected the ground terminal from the battery for 5 minutes and tried again. It started immediately and ran fine. I had a preliminary tune last fall. A mechanic friend wants to do a smoke test next.
Take a guess. I will try whatever you suggest. Whom ever comes closest wins the prize.
Using the F>A>S>T rule. (Fuel. Air, spark, timing) I guess Not enough gas in the tank.
STiPWRD
05-05-2020, 07:44 AM
I then I disconnected the ground terminal from the battery for 5 minutes and tried again. It started immediately and ran fine. I had a preliminary tune last fall.
So it starts and runs fine after you disconnected the battery, which resets the ECU. Doesn't that mean it's fixed? I'm confused. Was there corrosion on your battery terminals that was preventing a good connection?
Ajzride
05-05-2020, 07:55 AM
If it is a DBW car, the. Disconnecting the battery will trigger the idle re-learn, which would correct any bad map it had.
Bob_n_Cincy
05-05-2020, 12:25 PM
If it is a DBW car, the. Disconnecting the battery will trigger the idle re-learn, which would correct any bad map it had.
If it's a DBW, then pushing the gas pedal too far will cause a fault, putting the car in limp mode. Mine would still idle and only 20% power.
I went out yesterday and the car wouldn’t start. The check engine light that had always been on because of “ EVAP control valve shorted “ wasn’t on. My friend Randal came over with the Snapon diagnostic machine and it said that it couldn’t connect to the ECU. He pulled the ECU fuse, stared for a minute, pulled the next fuse down wiggled the ECU fuse and the car started. The problem was the female connector in the fuse box was not placed in the right place, but above where it belonged. The male fuse end was kind of touching it. Randal is a rock climber in addition to being the head mechanic at a Mercedes dealer. He contorted himself under the dash, pulled the box, moved the female connector to the right place and permanently fixed the problem. His 6th sense is amazing. I would have pulled the fuse but would never have looked at the box.
He gets the prize. I will install his Zero Decibel AWIC Sunday. He’s building an 818 coupe.