1991 190e 2.3 problems with surging/stalling/rough idle
 

Hello everyone... This is my first post on mercedesshop.com so I am very excited to join this community. Let me first give you a little background before I talk about my problem. I'm a 19 year old college student in Connecticut who purchased a 190e 2.3 with 111,000 miles on it exactly 3 years ago (when I got my license). My purchase came from Saving Auto in Stratford, Ct. This place was a seemingly sleezy used auto mart... at first, but the men who worked there were honest and true. I would HIGHLY recommend this used auto center for anyone looking to purcase a used car. The records of my car show that it was purchased new from the Mercedes Benz dealership in Greenwich, Ct in 1991 and was taken in for regular service until the new car warrenty expired. After that, the car was used infrequently and serviced at about 5-7k per oil change (strangely the woman who owned the car previously had replace over one thousand dollars in parts before selling the car, including a new radiator, fuel pumps, brake pads and rotors). Before purchasing the vehicle, I had the car checked out at a local mechanic in Norwalk, Ct by the name of IMPORTED CARS OF DARIEN. A friendly, local mechanic specializing in MB, BMW, and SAAB. My parents had owned a 1987 300E previously and once the warrenty on that car had expired, they used the imported cars of darien mechanic up until they sold their car in 1996. Anyway, since I purchased the car in December 2003 it has been a wonderful experience. No major problems, i've driven the car 11,000 miles total in three years- changed the oil at 3,500k. Then in August 2005 everything started to crash down. I garaged my car after work one day (my car is always garaged anyway) and went on a cruise with my family. Upon return from the cruise, (one week later) my car would have a flagrant and obnoxious idle that would make the driver feel as if he was on some carnival ride. Being the college student that I am, I decided to drive the car as long as possible without fixing the problem. Well about two weeks later the rough idle was so unbearable that I had to take it in. (note... The car NEVER stalled out EVER during this time, the guages all remained normal, and there was no smoke or bad smell eminating from the exaust) This idle would happen predominately when the car was in (D)rive or (R)everse and stopped at a stop sign/red light (another note. my car has automatic transmission). So my mechanic told me that the problem was due to a worn set of spark plugs and distributor cap/rotor. I dropped the $550 bucks and here is exactly what he put in the car... new motor oil, oil filter, distributor cap, distributor rotor, ignition wire (can't read handwriting on invoice, its a $100 part), and four new spark plugs. Well this fixed the problem completely.... for four months. Now in December, the car once again started the rough idle, it would shake constantly in gear when stopped and it would lag the acceleration when the automatic was switching into second gear. Once the car switched into second, it was smooth sailing from there. So far, the car has not stalled out. Just 3 days ago I brought it back to my mechanic and he said that the problem was too much guck and build-up around the rotating air-vent in the Idle Control Valve which would prevent it from allowing the proper amount of air in during idle, and this would eventually lead to stalling. So for another $70 he "fixed" the problem and the car was as I like to call it shake/rattle/rolling at stop signs just a couple hundred yards after leaving the shop. The only parts he put in this time were: 3 Vaccum Hoses, and 1 Carb (once again cannot read handwriting but its a $4 part). I called up my mechanic the following day, and in a rude and harsh manner he told me that even if I drop the $300 to purchase a new Idle Control Valve it MAY NOT fix the problem. I'm in a rut right now and I would appreciate any help that you could spare, along with tips and other quality mechanics/MB dealerships (Just like everyone on this forum, i've had HORRIBLE EXPERIENCES at MB of FAIRFIELD... they told me that there was a rodent's nest in my stereo compartment where there most definantly was not:mad: ). I'm a novice at best when it comes to automotives but I fear that whereever I go, they're going to continue to put $300 parts + $300 labor again and again until they solve this problem. THANK YOU

May I suggest that you add some paragraph breaks to your post.

As is, it is virtually unreadable.

Duke

sorry about that
 

Hello everyone... This is my first post on mercedesshop.com so I am very excited to join this community.

Let me first give you a little background before I talk about my problem. I'm a 19 year old college student in Connecticut who purchased a 190e 2.3 with 111,000 miles on it exactly 3 years ago (when I got my license). My purchase came from Saving Auto in Stratford, Ct. This place was a seemingly sleezy used auto mart... at first, but the men who worked there were honest and true. I would HIGHLY recommend this used auto center for anyone looking to purcase a used car. The records of my car show that it was purchased new from the Mercedes Benz dealership in Greenwich, Ct in 1991 and was taken in for regular service until the new car warrenty expired. After that, the car was used infrequently and serviced at about 5-7k per oil change (strangely the woman who owned the car previously had replace over one thousand dollars in parts before selling the car, including a new radiator, fuel pumps, brake pads and rotors).

Before purchasing the vehicle, I had the car checked out at a local mechanic in Norwalk, Ct by the name of IMPORTED CARS OF DARIEN. A friendly, local mechanic specializing in MB, BMW, and SAAB. My parents had owned a 1987 300E previously and once the warrenty on that car had expired, they used the imported cars of darien mechanic up until they sold their car in 1996.

Anyway, since I purchased the car in December 2003 it has been a wonderful experience. No major problems, i've driven the car 11,000 miles total in three years- changed the oil at 3,500k. Then in August 2005 everything started to crash down.

I garaged my car after work one day (my car is always garaged anyway) and went on a cruise with my family. Upon return from the cruise, (one week later) my car would have a flagrant and obnoxious idle that would make the driver feel as if he was on some carnival ride. Being the college student that I am, I decided to drive the car as long as possible without fixing the problem.

Well about two weeks later the rough idle was so unbearable that I had to take it in. (note... The car NEVER stalled out EVER during this time, the guages all remained normal, and there was no smoke or bad smell eminating from the exaust) This idle would happen predominately when the car was in (D)rive or (R)everse and stopped at a stop sign/red light (another note. my car has automatic transmission). So my mechanic told me that the problem was due to a worn set of spark plugs and distributor cap/rotor. I dropped the $550 bucks and here is exactly what he put in the car... new motor oil, oil filter, distributor cap, distributor rotor, ignition wire (can't read handwriting on invoice, its a $100 part), and four new spark plugs.

Well this fixed the problem completely.... for four months. Now in December, the car once again started the rough idle, it would shake constantly in gear when stopped and it would lag the acceleration when the automatic was switching into second gear. Once the car switched into second, it was smooth sailing from there. So far, the car has not stalled out. Just 3 days ago I brought it back to my mechanic and he said that the problem was too much guck and build-up around the rotating air-vent in the Idle Control Valve which would prevent it from allowing the proper amount of air in during idle, and this would eventually lead to stalling. So for another $70 he "fixed" the problem and the car was as I like to call it shake/rattle/rolling at stop signs just a couple hundred yards after leaving the shop. The only parts he put in this time were: 3 Vaccum Hoses, and 1 Carb (once again cannot read handwriting but its a $4 part).

I called up my mechanic the following day, and in a rude and harsh manner he told me that even if I drop the $300 to purchase a new Idle Control Valve it MAY NOT fix the problem. I'm in a rut right now and I would appreciate any help that you could spare, along with tips and other quality mechanics/MB dealerships (Just like everyone on this forum, i've had HORRIBLE EXPERIENCES at MB of FAIRFIELD... they told me that there was a rodent's nest in my stereo compartment where there most definantly was not ). I'm a novice at best when it comes to automotives but I fear that whereever I go, they're going to continue to put $300 parts + $300 labor again and again until they solve this problem. THANK YOU

A simple thing I would check - what is the brand and part# of the plugs installed in your car? The symptoms could be caused by many things, but notoriously by Bosch platinum plugs. Bosch copper are correct.

Steve

Mass Air Filter
 

Try as Mass Air Filter......Get a used one first to confirm the problem, then transition to a new one. Most electrical parts are not allow to be given back once paid. So I got a used one from a Mercedes Junk Yard for 1/3 of the price.

Could be airflow meter, bad plug wires, the afore-mentioned sparkplugs (use Bosch Copper), check for air leaks around hoses at airflow meter, over-voltage relay fuse may have corroded terminals, fuel distributor governor, CIS temp sensor, CIS control unit, fuel pump relay... the list goes on...

Good Luck - I fought similar problems with my 190E 2.6 - had to replace the fuel distributor - only $500+

bnc

Have you tried a can of good fuel injector cleaner? Have they checked the O2 sensor? Have they checked to see if the Fuel Mixture is correct at idle?

I have a 1986 that had a rough idle. New wires and plugs and cap and rotor, fuel filter, O2, blah blah blah were all tried. Fixed it with a new AFM boot and replacing every rubber vacuum connector. Still was a hair off so I got the Heavy Duty Bosch Copper plugs. Ran great but still not as smooth as I thought it should be so I got a can of BG44K fuel system cleaner. She now is almost as smooth as my 2003. Still has some bumps once and again but I am thinking that is my cracked exhaust manifold letting in outside air or letting out too much exhaust and thus making my O2 get false readings and my EHA to over correct. But check or have checked the following.

Rubber Intake Boot between AFM and Throttle Body
Vacuum rubber connectors all throughout the engine bay
Check Mixture
Check O2
Verify Copper Bosch Plugs used and Gapped correctly
Clean IACV and AFM and intake area with Liberal Amounts of Carb Cleaner
Check Water Temp Sensor for proper functionality
Verify OVP relay is functioning properly

If needed I have a spare OVP I can send you for a small fee that works perfectly. I also have a spare IACV, but mine is a 3 wire deal with the adjuster knob on it and you most likely have the 2 wire one with no adjustment.

Like Jamie says above you have to systematically go through each thing listed until you find the culprit. If you take it to mechanic they may charge you way too much to just chack half the things listed above. Time to roll up your sleeves and get personal with the car :)

1991 mercedes 190e
 

new user
i am wondering if its ok to use the pulse plugs to help me with the same issue

My son has a 1990 190E and is having the same problem, does this car have to have the non resistor plugs?

yes all Mb cars are non resister plugs, the wire set has the resistance bilt into them.