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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #1 ·
Hey guys, i have a 1987 190e 2.3 16v with manual transmission. I attempted to adjust my idle and failed. I was turning the allen socket in this unit.



I had the car running when i was messing with it. While i was adjusting it, the car stalled and from there, it wouldn't start again.

The car was running fine before (except with the issue with high idle around 900-1k rpm. The fuses in the OVP is fine and it is also a new replacement unit. I checked the spark and it is good. The fuel is also pumping. The sparking chamber looks flooded when i had the spark plug out for the spark test. It crank up smoothly. Doesn't sound like any misfire or anything.

As of now, the car would crank but won't turn over. I tried spraying started fluid also just to test the fuel system, but no start.

I removed the valve cover to check the chain, camshaft, etc. and everything looks fine inside.

Can a bad water temperature sensor for the CIS prevent the car from turning over?

I am currently stuck. Any help would be great.
 

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'87--190E 2.3-16v(being rebuilt), '99--C230 Kompressor
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3,488 Posts
idle air and fuel mix ratio is something that i personally leave to my now trusted mechanic, because he has the specialized tools and info to tune the car to factory spec and it's done right the first time.

also depending on how much you "adjusted" it you have have bottomed out the unit
 

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93 190E 2.6; 82 300 SD Turbo
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1,689 Posts
The tower you are adjusting is called the lambda tower. It is not an idle adjust screw. It is for adjusting the air/fuel mixture. You have adjusted it way too much one way, and now your call will not start. I've done thing a few times on a 560SEL I'm working on, simply adjust it back the opposite direction to that which you adjusted it in the first place..and then try to start the car.

To properly set the air/fuel mixture, you need to attach a voltage meter across pins 2/3 of the x11 diagnostic connect located on the drivers fender (a short round connector,) monitor this voltage if you take it and divide it by the current battery voltage then multiply by 100 you will get the duty cycle of the motor. Adjust the screw on the lambda tower until you achieve somewhere in the vicinity of 40-60% depending on your preferences (one way is running leaner, the other way richer, I cant remember which).

Your high idle is probably caused by something else, a vacuum leak, a shoddy idle control valve, idle control unit or something else. I'm chasing this down on the 560SEL..its not fun.

Hope this helps. Welcome to CIS Hell
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #4 ·
Thanks for the insight guys. I think the lambda tower have been adjusted in both direction. The neighbor "help" me look at my system and went of twisting and turning it all over the place. I was wondering if there is a max turn in or out?
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #5 · (Edited)
update: i did alot of testing and trying to figure out the problem. I check power for all the unit involving the intake side. I noticed a wet build up on the lower hoes of the IACV. I pulled it out and there was alot of gasoline in the valve. I guess when i messing with the gas and air mixture, i had it too lean for too long and the IACV got flooded somehow.

I went to buy a multimeter earlier today and realized that i don't know how to use one. But i am learning quick. What i need to know is, can i figure out the air fuel ration (Duty Cycle) with the key at ON with the engine off? Will turning adjusting the lambda tower, show some number/percentage change on the multimeter with the engine off and key to ON?

Im making some progress and hope to solve this soon. Thanks for the help guys.
 

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93 190E 2.6; 82 300 SD Turbo
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update: i did alot of testing and trying to figure out the problem. I check power for all the unit involving the intake side. I noticed a wet build up on the lower hoes of the IACV. I pulled it out and there was alot of gasoline in the valve. I guess when i messing with the gas and air mixture, i had it too lean for too long and the IACV got flooded somehow.

I went to buy a multimeter earlier today and realized that i don't know how to use one. But i am learning quick. What i need to know is, can i figure out the air fuel ration (Duty Cycle) with the key at ON with the engine off? Will turning adjusting the lambda tower, show some number/percentage change on the multimeter with the engine off and key to ON?

Im making some progress and hope to solve this soon. Thanks for the help guys.
Try this to start your car back up, if the tower is too lean, crank it down a little, turn the key, keep doing this until you get it to start or atleast fire a few times...if its too rich turn the opposite. You'll have to adjust until you can get it start again and do a proper adjustment..

The procedure is as follows:
1) + probe in pin3 of x11 port
2) - probe in pin2 of x11 port
3) Key On, Engine Off Should Read 70% Duty Cycle for Federal, 85% for Cali I think

If your multimeter does not have duty cycle, simply take the voltage reading, divide it by the battery voltage and multiply by 100..and you'll have duty cycle

4) Start Engine
5) The voltage should hold 50% DC for a min or two..then the CIS-E will take over and you should see a different number, probably close to battery voltage if your real lean
6) With engine on, adjust lambda tower, slowly, do not press down hard or it will stall. After you've made and adjustment, let the engine stabilize, look at meter..aim to get 50% or so.

Also update your info with your location and all that good stuff so the people here know where your at
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #7 ·
JamesDean- Thanks for the info and procedure. I will be getting back at it once im home from work.

The thing with the lambda is, it was adjusted way off. Now its to a point that it is impossible to know which way to turn it. Im wondering if theres a max turn point in any direction. That way i can get it to that point and start over. If not, im screwed.

Ill keep the thread posted on my progress. I was also spending all night reading the PDF troubleshooting manual. I am also going to be doing the diagnostic procedure to check all of the components that affect the car starting.

I also noticed that the o2 sensor light is on. Does this mean that the o2 sensor is bad, or does it mean there is a false code? I look under the passenger carpet and theres no switch to reset/check. I also do not have a lil box in front of the battery to check with the pins for the error blinks. Its weird, i don't see anything where i can get an error code.

I am updating my info for better help. Thanks.
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #8 ·
I just checked my Duty Cycle and it reads 44.4% with the ignition switch to on and car off. I can't turn the motor on and check the Duty Cycle when the motor running of course. So how do i go about adjusting the Duty Cycle with the engine off? I tried turning the Lambda allen screw and the numbers don't change. I know that the percentage for the Duty Cycle with the engine off should be 75% or 80%. Since i am in California it should be around 80%. I am going to check some other stuff while i wait for some help. Thanks.
 

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93 190E 2.6; 82 300 SD Turbo
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Cali i think is 85% key on, engine off

My 420SEL, reports 30% with key on, engine off
My 190E reports the proper 70% with key on, engine off.
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #10 ·
Cali i think is 85% key on, engine off

My 420SEL, reports 30% with key on, engine off
My 190E reports the proper 70% with key on, engine off.
So, how do i fix the issue? how do i get my 190E up to 85%?
 

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93 190E 2.6; 82 300 SD Turbo
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For Cali cars you have to do a special thing to get the gizmo to output the on/off duty cycle:

For California cars, starting in 1988: Press the push button switch on test connector X92 (passenger side, between the two firewalls) for two to four seconds. The LED will flash once, indicating no fault code is stored in the system. Now press the switch again for two to four seconds. The LED will be on continuously, and the injection control is switched over to an on/off ratio output.

If the LED flashes more than once, count the flashes, they indicate a fault in the system and we can go from there in diagnostics...
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #12 ·
Thats what i was looking for before checking the Duty Cycle. my vehicle is a 1987 190e 16v. I do see the x92 connection anywhere. Not sure what to do to figure out if theres any trouble code or not. All i know is the o2 sensor light is on in the cluster.
 

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93 190E 2.6; 82 300 SD Turbo
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Ah ok so your before the 88 DTC stuff. Then I think you should be like the rest of us...

Do you have the PDF on the CIS system for your car? Send me a PM or email if not...
 

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1995 S420, 1987 190e 2.3 16V , 2008 CBR600RR
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199 Posts
Discussion Starter · #14 ·
I do have the PDF file. I've been reading and re-reading the system. You can say, im more of a hands on mechanic kind of guy. when it comes to electrical, im not so good. If you can point me towards the right direction and i'll see if i can follow direction. :D
 
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