Car starts and runs as soon as I hit the throttle it dies??


Asked by Jul 23, 2015 at 12:46 AM about the 1986 Mercedes-Benz 420-Class

Question type: Maintenance & Repair

Hi all, my father has a 1986 420sel he
has just fitted another engine to it.
It is a 500 engine but the problem is
as soon as you hit the throttle it dies.
It will idle ok can any body help us
Thanks luke

1 Answer


Most likely it is your ignition coil or spark plug wire. Where these replaced when the newer engine installed? If not that could be the culprit. If they were check your fuel pump, cable battery connection, ignition control module, and the crankshaft Position Sensor. Let me know if that helps.

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