1994 Mercedes Benz E420 No power

1994 MERCEDES BENZ E420
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LINAKI
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1994 Mercedes Benz E420 V8 Two Wheel Drive

I have a 1994 Benz E420. I replaced the rocker cover gaskets and since then I have loss of horse power. I checked and rechecked the gaskets and covers and all is ok. I have cleaned the MAF and still the problem is there. It seems to be more when the car warms up. I have heard that the mass airflow sencor is common on these cars but the problem only started after I changed the gaskets. I have checked everything and I am baffled. Please help me figure this problem out.
Mar 13, 2010 at 9:06 AM
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RASMATAZ
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Lack of acceleration,chugging,hesitating,bogging etc. could be caused by one of the following below.

Inspect and test all the following listed below and get back with some results

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard.
Mar 14, 2010 at 6:08 AM
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LINAKI
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Thanks for the reply. I had the car scanned and these are the following codes it had pulled from the ECM.

1) Idle speed control sensor
2) Upshift delay switchover valve
3) Intake air temp sensor
4) ECT Senssor
5) Speed signal sensor
6) Secondary air injection sensor.

The plugs have just been done and the wires are fine. I will check all others mentiond.

Thanks
Mar 15, 2010 at 2:36 PM
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LINAKI
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Thanks for all your help but I figured out the problem. It was after all a plugged catalytic converter. I tested it by touching the pipe coming from the one converter and it was cold to the touch. I cut it off and low and behold the power was back. I have since then put a new converter on there and all is great!!!

Make sense when the car would go up hill it was worse than ever.
Mar 18, 2010 at 3:37 PM