cheeseraid

Hey,

I'm new to the whole MB thing, Gm's are what I know. I recently picked up a 190e 2.6 with 87,000 on the clock. I have changed the spark plugs, wires, cap, rotor, fuel filter, valve cover gasket, air filter, all vacuum lines, oil cap, rad cap, motor mounts, tranny mount, new brake pads and rotors in the last 2 weeks (all oem stuff). A couple of days ago the car starting a little weird. Surging while going down the rotor at about 55mph. I checked the spark, it was fine. Check for vacuum line leakage, nothing. Um weird. Well, I went to start it up three days ago. It took it longer than the normal 5 turns to start. Idle was able to be felt in the car. It was like my Trans Am with the 383 and the big cam. I did some research on it. I checked the over voltage thing, no corrosion and no bad fuses. Check the fuses on the car, nothing bad. Um I'm starting to get stumped. I don't really know a lot about the CIS-E system. I don't have a connector the fuel line size so I can't check the fuel pressure. I checked the accumulator, it's fine. I found online about the eha, and tried tweaking that. It ran a lot better till I got to walmart (at red lights it was still a little ruff) . I came out and started it. Fired in 2 clicks, then revved to 1000 rpm. From there is jumped from 1000 to 500 to 1000 to 500 to 1000 with one second intervals. Lasts for about 5 minutes then will idle at 700 like normal. I turned back the eha, still does it. Where do I go from here? Any help would be much appreciated!

slk230red

The first thing I would do is check the vacuum hoses going to and from the Idle Control Valve. Second, I would remove the Idle Control Valve and look inside the connection fittings to see if it is clean, they sometimes get gummed up and require cleaning. Also, do a quick operation check to make sure it clicks and opens...you can use a 9v battery for this test. Just touch the 9v battery to the ICV contacts and it should operate.

The idle control valve on my 2.3 looks like this:

cheeseraid

There is nothing wrong the idle control valve, or the hoses. The guys at a MB place said it was something to do with the air fuel mix. I tried adjusting by the tower next to the fuel dist. no luck there either

slk230red

Well, if the guys at the MB place says that there is nothing wrong with the Idle Control Valve circuit, then I guess it must be OK. Are both fuel pumps operating?
What I would do is, remove the air cleaner and observe what the air flow plate is doing when the idle increases. If it is going down and the idle jumps up, then it is getting vacuum from some source.
I can duplicate your idle problem, 1000 to 500 to 1000 to 500 to 1000 with one second intervals. I'm sure the guys at the MB place will figure it out.

Here's a link to a W201 Service Manual:

http://web.archive.org/web/200606021...01_Chassis.htm

Good luck,

Dave

cheeseraid

well the guys at the mb place got no idea whats up with thing. i decided to figure it out my self. tommrow i plan to check the pumps. im thinking about taking a 2 liter and cutting it in half. Its 1 liter for 10 seconds of key on to check them i think. would resister plugs cause it? i heard these things only like non-resister plugs am I right? i still think its either something came loose in the pumps or injectors or its the plugs. any more ideas?

slk230red

1. I think the delivery rate is more like 1 liter in 40 seconds. Check testing procedures here:
http://web.archive.org/web/200606021...01_Chassis.htm

A bad fuel accumulator can also cause a low fuel delivery rate.
Also, a clogged filter located at the input of the fuel distributor could cause a low fuel delivery rate. See below photo:



2. You should be using non-resister plugs due to resistance in the OEM connectors, if those are what you are using. I don't think the plugs would cause your problems, but I do know the engine doesn't run as well with resistor type plugs. Which brand/number spark plugs are you currently using?

3. If your engine starts to idle up and down, try disconnecting the connector at the Idle Control Valve to see if it changes.

4. Other things to check:

A. Coil
B. Air Guide Housing (large rubber piece that is between air flow housing and throttle body). Sometimes they are cracked or not seated properly, causing vacuum leaks.
C. Fuel pump relay...known to have cold solder joints on circuit board.

Do you know if the MB guys checked the above items? It's good to keep an accurate log.

Good luck,

Dave

cheeseraid

the idle air valve isn't the culprit, the mb guys checked that. they checked the fuel accumlater. they said they didnt think it was fuel, they think its a sensor. the coil came back good. they checked it by an ohm meter. the lamba checked for air/fuel ratio was good. the plugs in it right now are bosch platnium. it liked those for about 3 days. it had the h9dc0's in it. they were burnt real bad. i have some more on order. i dont know if there really no resister or not but i ordered them hoping. i'll check that filter tommrow.

slk230red

I tried the Bosch Platinum once and the car ran lousy, so I switched back to the standard type.
What was the last thing done to your car before you started having idle problems?
Lately, people have been having idle problems after they clean the throttle housing.

Sensors???

Have you checked the O2 Sensor?

Have you checked the Throttle Position Sensor?

Have you checked the Engine Coolant Temperature Sensor...if yours is the 4 pin type, it sends information to the CFI Module and the Ignition Control Module. Check ohms across pins 1 & 3, and 2 & 4. The resistance will drop as the engine temperature rises. High reading = cold engine. Mine reads 1.7k across pins 1 & 3 and 2 & 4 when checked cold in the morning in the garage.
Check yours and look at the testing procedures according to the manual.

Good luck, I hope you can isolate your problem.

cheeseraid

I didnt think it would be the o2 or the tps. I mean if the tps is going south it wouldn't cause that drop in power while going down the road. The tach does not drop any rpm's, it just loses power. I wouldnt think it would be the o2, I have the original o2's in my trans am (140,000 on them) with no need to replace them. I pulled it out, checked the resistence and it was fine. The water temp sensor kinda makes sense. I ordered a new one for mine. 18 bucks isn't to much to pay. I checked mine and it was good but that dosent mean it is. Thats not going down the road. I think I figured out the idle problem, I'm waiting on that part to come in. I'm thinking it's the tower for the air/fuel ratio. Somebody has played with it in the past and the ball isn't in there no more. I couldn't turn the allen head bolt so I pulled it out. The spring isnt retaining tension. I started it without the tower and noticed the adjustment thingy keeps turning counterclockwise leaning it out. I put it back together and watched it. I did the same thing! That possibly could cause it loose power. What I cant figure out is how did it read the right air fuel ratio when they ran the lambda on it? but my luck it wont fix the problem. This car is starting to remind me of my girlfriends trooper. It died one day, it took 3 months to figure it out. the damn cam gear slipped loose 1 deg. I hope this car dosent take as long to figure out. lol

cheeseraid

where the hell is the fuel pump relay on these cars? I was going to check that but cant find one. Nor can I find a fuse for the pumps.

cheeseraid

well the water temp sensor is reading 4.7k at 42 degrees outside. Motor is cold. next sensor up on the head wont come loose. the next (last one towards the front) is .82 k. more specs in the next post

cheeseraid

i think i fixed the idle problem! i tore the air flow sensor out to fix the air fuel control. fixed that. made a temp gasket for the air fuel control. turned the setting 1 turn foward. its sitting here idle'n fine except alittle missin, i think is due to the plugs. check out my myspace page here in about anhour for pics of my ride. myspace.com/cheeseraid i'll keep u guys informed

slk230red

Yeah....the tower for the air fuel control mixture setting is weird. Mine still had the factory ball bearing seal in it until 2 weeks ago. the correct way is to completely remove the tower and install a new one with access. I cut it off just below the ball bearing and the spring inside stayed intact. Then, I was able to put the allen wrench in the top, push down, and adjust it clockwise and counter clockwise. As it turned out, I only needed to turn mine about 1/8 to 1/4 turn clockwise and it smoothed out the idle and raised it slightly.

Photo of cut-off tower:



You might want to check this link about non-resistor spark plugs.
http://www.mercedesshop.com/shopforu...d.php?t=197392

Also, the Fuel Pump Relay is behind the battery. Remove the plastic cover and you will see the FPR along with OVP relay (another problem source, especially if it has a blown 10 amp fuse or corrosion inside). The OVP relay protects the electronics in case of a power surge or reverse battery connection.
You will also see the CFI Control Module.

Example of Fuel Pump Relay:





Cold solder joint:



OVP Relay:





Sounds like you are getting to know your car quite well. Please post what you find out resolves your problem.

Good luck,

Dave

cheeseraid

the pics are on my myspace of the car, only 3 pics though. I forgot to put the memory card in lol. I'll put more up later or tommrow. www.myspace.com/cheeseraid

Ya im starting to learn my car lol I knew I would figure something out sooner or later. I havent take it for a ride yet so I dont know If I fixed the stuttering or not. It idle's better, actually at least it will idle. I warmed the car up to 80C and started it a a few times. It started fine. Ill check those things tommrow. Its friggin cold out (38F). Its startin to get better. I guess this is what I get for a car thats 16 years old and sat for 9 years lol Thanks again for the info. Check out those pics and Ill get back to you guys tommrow!

cheeseraid

well its still stuttering and idle'n weird. still trying to figure it out

slk230red

One question, was it having these problems before the items were replaced that you listed in post #1?

If it were me, and the air/fuel mixture adjustment won't smooth out the idle, then I would start from scratch and go over all of the basics.

Spark plug wires-are they the right type?
Spark plugs- are they the right type?
Coil
Distributor cap
Rotor-there are 2 completely different types for my '93 2.3
Compression test- you could have a burnt valve, or worse...the beginning of a bad head gasket between cylinders.
Fuel pump- pressure/output test
Fuel distributor-is the plunger sticking
Fuel injectors-are they producing the proper spray pattern
Fuel injector seals- are they leaking
Crankshaft Position Sensor- check resistance, or could be dirty at flywheel end.

Just some ideas. I wish I knew the answer to your problem. I know these things can be frustrating.

Dave

cheeseraid

ya it was having those problems before i started adding new parts. Everything is good as far as I can tell. Im going to recheck everything this friday. Im starting to think its the head gasket, reason being is that everything else looks good and the hesitation is starting to be more pronounced. Like I said, friday hopefully I'll have the time to re check everything and do a compression check. Hopefully soon I can figure it out.

slk230red

A compression test would be a good idea before pursuing other options. Replacing the head gasket isn't too bad if you're doing it yourself, but very pricey to have it done.

cheeseraid

Well the motor checks out good. The motor is losing about 2 pounds at the number one cylinder but otherwise is good. Everything else seems to be fine. I cant figure out why it had quite a bit of gas in the intake plenum. The injectors are fine. Would the throttle body or the throttle position sensor cause what im feeling in the car? I noticed today that driving it down the road, if my foot is on the gas pedal its fine but as soon as I let off its trying to "learn" the position of the throttle. Same with when I start it up sometimes, it seems like its trying to "learn" where the throttle is at. Anybody know what the sensor's ohm reading should be? New Bosch plugs fixed the idle problem. It did not like those platinum's.

slk230red

Check your micro switch on the throttle assembly. Make sure that the bracket presses against the roller on the switch enough to close it.

cheeseraid

the idle micro switch is engaging fine. still hunting for the problem...