500sl hesitation on acceleration

[Robistock]

I have a 1990 500sl,and recently had new injectors installed as well as a new EHA valve.The car starts more or less ok when cold but very difficult when warm.If I press the accelerator pedal once when hot she will start better.This leads me to believe that it may be the fuel accumulator, but when accelarating from a stop position ,the car starts ,hesitates and then goes,this does not happen when the car has been running for a while.
I also have new spark plugs and the car was also serviced.
Any ideas

[aam]

Originally Posted by Robistock

I have a 1990 500sl,and recently had new injectors installed as well as a new EHA valve.The car starts more or less ok when cold but very difficult when warm.If I press the accelerator pedal once when hot she will start better.This leads me to believe that it may be the fuel accumulator, but when accelarating from a stop position ,the car starts ,hesitates and then goes,this does not happen when the car has been running for a while.
I also have new spark plugs and the car was also serviced.
Any ideas

1. Check the ign. rotors and the adapters have been upgrated to H. D.
2. 0/2 sensor for touching the drive shaft.
3. Mass module.
4. Fuel pumps. PSI. Test.
5. Temp. sensor.
Regards.
aam.

[Robistock]

Originally Posted by aam

1. Check the ign. rotors and the adapters have been upgrated to H. D.
2. 0/2 sensor for touching the drive shaft.
3. Mass module.
4. Fuel pumps. PSI. Test.
5. Temp. sensor.
Regards.
aam.

Thanks for the info,I have 2 new fuel pumps, and the way the car drives it seems a fuel problem when cold once you drive 15 miles the car is great,with no problem.
By the way what is HD
regards
robert

[aam]

Originally Posted by Robistock

Thanks for the info,I have 2 new fuel pumps, and the way the car drives it seems a fuel problem when cold once you drive 15 miles the car is great,with no problem.
By the way what is HD
regards
robert

Hi Robinstock.
Two thing come to my mind.
1. Ignition cups, rotors and adapters have been upgraded to ( Heavy duty.)
Open them up ck. for cracks. And clean, if ok.
2.The other is the temp. sensor.

PS. Didn't see the question.
Check the part number for the rotor adapters, you can't put the new to the old.
You must change the adapters.
aam.