97 E320 Running Very Rough
 

Need help
The car was in an accident, has approx 13,000.00 miles
After I start the car it runs almost smooth but when pressing on the gas pedal it starts to backfire and stalls. There was no damage to the engine.
While trying to start the car I disconnected different sensors and plugged them back, disconnected and connected the battery.
What could be the problem?
Thank you

Look to the air piping between the Air Mass Meter and the throttle assy. Sounds like you have a big air leak.

Thank you
I will look at it this afternoon

Thanks Steve

How can I tell if the Air Mass Meter is working properly?

Its pretty hard to do without some equipment. The prefered way is to look at the adaptation values and test to be sure they are not something else.

If an AMM is the cause of your problem it is pretty bad. The adaptive values should be near the max. Lower partial around 1.25 or above.

The actual output voltage can be read but a 10% skewed AMM would be about impossibly to condemn from the results and it could cause such problems.

I looked at the engine compartment, it looks like no demage anywhere to the engine but when the car is running I hear a hissing noise (like some air leak) on the right side of the engine (i can not see anything there the car does not want to run
( BEFORE IT HAD AN ACCIDENT AND I WAS TRYING WITHOUT RAD JUST COOLING PIPES CONNECTED TOGETHER)
the car has about 12000milesdoes not want to run smooth and when pressing the accelerator it back fires

please help

When I start the car it is running but rpms are going up and down from 500-700rpm.
When I press on the gas it starts to backfire and or just shuts down, I checked for air leaks but do not see any broken parts anywhere.
What are the possible couses for this one.

Thank you

Why not have the OBD scanned?

Not sure what is obd but the car is out of town and I need to tow it to the shop ,but I was hoping that I could fix it myself

This sounds silly but check to make sure your exhaust isn't plugged or bent. A flow restriction like this will allow the car to start but as soon as you increase flow the car will cut out. Worth checking if the cars been in an accident.

all exhaust looks untouchedind in perfect shape but maybe the catalityc converter is plugged from overflooding, someone told me but I did not check it yet , is it possible?

Vacuum hose is off?

I am going to put the car on the hoist today and look very closely at all vacuum connections.
Any other ideas greatly appreciated

Is it possible to check for air leaks with vacuum preasure tester and how would I do it?

I would just check the vacuum connections first and see if something came undone. That's what I thought of when you said "hissing noises". I know many on here recommend the miti-vac or something like that. I haven't used one yet, so maybe somebody will chime in.