Car Problems

[blackc220]

I have a 95 C220
When ever the car warms up and come to a stop, mostly when
the A/C is on, the idle surges. I checked fuel pressure, and its good. I checked the coolant temp sensor and its good, the car
has a new eng harness, A/C compressor, over voltage relay.

Anyone have any ideas.
Thanks

[jmerritt]

i have the same problem, i usually put my car in "N" when waiting at traffic lights i get that surge in revs as well, i think that the car just needs a bit more power to run the a/c or what ever needs the power, but it quickly levels off.

[loudandheard]

I'm having the same problem also, but my car is a 96 c220. Does it seem like your car is hesitating when it shifts when you start driving?

[blackc220]

still not running good - when the eng gets warm and i come to a stop the car almost dies, when i accelerate from idle, it hesitates,
it also does it when moving from P/N to D/R exspecially with a/c on, theres no check eng light on - no codes


Ive checked cam adjusters, vaccum leaks, ive put a new ME (eng computer), M16 motor (throtle control & idle control), check fuel
pressure, checked fuel pressure regulator, new coils, new coil
harness, over voltage relay, coolant temp sensor, ac compressor,
new eng harness, new mas, new spark plugs, suppresors, plug
wires, plug wire ends at coil, hooked up to a scope and check
the ignition pattern - good, cleaned intake, adjust throttle and idle linkage

any ideas would really help
thanks

[loudandheard]

Wow, that sucks. I was having the same problem and still no check engine. I came off the highway and it got worse almost died on me and it shook horribly. I finally got the CEL to come on and it turned out to be that there was a misfire in cyinder one, so I changed my plugs and wires. Every thing seems fine now. Does your car hesitate through shifting?

[blackc220]

no it doesnt - only off idle

i checked compression - good through all cyl
i benched tested all injectors, patterns where good and it didnt leak

so im all out of things to test, anyone got an idea


thanks

[jnolte]

perhaps its a wiring harness thats making everything go whacky!

[omeyhomey]

your idle control valve may be dirty, clean it with some teflon safe throttle body cleaner and your idle should improve greatly. hope that helps

[jnenad16]

he doesnt have an idle control valve.
the thing that comes to my mind is a bad crank position sensor. also, have you checked the voltage output of your alternator?
you could also have a vacuum leak somewhere along the intake, and if this problem occurs mostly when the car warms up, it would most likely be a bad intake manifold gasket or some other rubber vacuum piece.
another thing you should check out is the O2 sensor. if you have and access to any mb oem scanner(SDS, baum, snap-on), check the signal of the front sensor, it should oscillate on idle(from 0.1V to 0.9V and vise versa) and then steadily level off under partial throttle. if the signal is steady(constant voltage), the sensor is dirty and needs replacement.

nenad

[blackc220]

ive checked the o2 sensors, they are working good
the alternator is brand new - output is good
theres a new wiring harness on it to the computer
ive checked for vacuum leaks - none
the throtle body has been cleaned

thanks for all the ideas and all the help