Q: Rough idling and lacking horse power - 1982 Mercedes Benz 380SL

asked by on

I have a 380SL that sat around for 9 months and has some engine problems. The odometer is broken, so I don’t know the mileage on it. I have quite a few vacuum leaks. I put in all new fuel injectors, gaskets, hoses, spark plugs, leads and a distributor cap. I checked the distributor and a many of the valves. Everything seems to be working OK. My friend helped me hook up the pressure gauges and set the fuel pressure of the warm up regulator and set the timing. It passed the smog check in California. So my car runs the way it’s supposed to when I start it from a cold start. It gets good idle rpms, fuel economy, horsepower, temperature, etc. It’s perfect! But when I start the car after the engine has been warmed up or hot it idles rough with a wave of rpms, awful fuel economy, hardly any horsepower and almost does a complete stall. It does this consistently. I was thinking it might be the ignition control unit, temperature sensor, over voltage relay, O2 sensor or something else. Do you have any ideas on what might be wrong?

Hello. There could be a problem with the coolant temperature sensor. I would also suspect that there could be a problem with the ignition control unit. The fuel pump could also be contributing to the problem you are experiencing. If the fuel pump is weak or not getting the proper voltage, this may cause a problem like the one you describe. Have a certified technician, like one from YourMechanic, diagnose the rough idling in order to make necessary repairs.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Rough idling and lacking horse power - 1982 Mercedes Benz 380SL

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: When accelerating from standing stop engine hesitates

I would recommend checking the mass air flow sensor as this is a commonly known part that can cause this kind of loss of power. This regulates the air intake into the fuel injection and ensures a proper air/fuel mixture....

Q: Car stop accerating while I was driving

Hello. The vehicle stalling can be caused by several faults. Typically to blame are fuel delivery and spark. You can perform a series of tests to eliminate some of the options. Start by using a spark tester to see if...

Q: Bonjour j'ai une voiture vw amarok 2011 2.0 TDI le code de défaut p0087 mes je trouve pas la panne. Merci de votre réponse

Hola. El código P0087 aparece cuando el sistema de combustible ha perdido presión de combustible y el sensor de presión de combustible lo ha recogido. Revise el filtro de combustible, las líneas de combustible para ver si hay una restricción,...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.