Low revs when cold 16v 1986 190e
 

When I get the car to finally light up in the morning the car the idle revs are unusually low (500) and then as the car heats up the idle revs increase to 1000 sometimes 1200 or so.

Could this be related to the temp. sensor that monitors the coolant temp? If that is the case, could that also inhibit the cold start value from working properely as well?

Also, when it is cold I have hestitation, most noteable when I round a corner or shift. Any ideas?

Thanks in advance.

Gards

Is your ABS light on?

No, but I don't recall off the top of my head if that light is burned out. I am pretty sure that it isn't not burned out.

Would that or could that be an OVP issue?

Thanks,

Gards

When I had a bad OVP it was a horrible cold start then fine when warm except for the ABS. Dont think I had high rpm's like that but I can't really rember.
The OVP should have a fuse you can check but I think it usualy outlasts the rely.

good luck
Marty

Thanks for your replies. I did check the ABS light and it does work and is off.

Thanks,

Gards

i need help also
 

just happened on this question i have the same motor. when cold it runs from 500 to 1500 and also stalls on every ocassion until it gets hot it also takes some cranking of the starter to fire up. my abs light comes on and it stays on. so where do i look first please regards ken

Normally this is the Water Temp Sensor. It tells the CIS-E system when to make the mixture more lean or more rich depending on engine temp. Also fires the cold start valve. Idle will wander when cold and this is bad. At least mine did.

Edit: Check the EHA thread near the end I have posted the chart of values for the Water Temp Sensor! Also make sure you check the wires, my connectors fell off my wires and I had to improvise and make new connectors!

Thanks for the replies. I will check the temperature sensor. Do you know which one is the temp and how to test it? I didn't mention this in the beginning but the car is a euro (do know if this makes a difference or not).

Thanks,

Gards

Temp sensor for CIS is the one with 2 Posts on it. Both individual with the connector covering the post when plugged in. Only one with two individual connector with a single wire on each. Actually now after looking at the parts store I am wondering if you even have this sensor since I believe you engine has KE-III Jetronic as opposed to my 1986 with KE-II. But check it anyhow I guess. It should as the 2.6 with KE-III has either the two pole version or the newer 4 pole version. So I have to assume the online parts place I go to does not list it. You can go to *********************** and select MB 1986 and the standard 2.3 8 V engine and then go to Fuel Injection and Water Temp Sensor. There is a picture there and see if you have that sensor on yours.

Edit: I just looked up for a 1987 16V and it is listed there, just not in the 1986 listings. I do not recall there being any change to the engine between 1986 and 1987 and the only thing I recall for Euro version was lack of a cat and higher redline!

Thanks for the infor. I apologize for taking so long to reply. The email feature that notifies when a post has been made did not work.

I will take a look at your suggestions and let you know what I find. Thanks again for taking the time to respond.

Gards

Just a side note . . . Does this water temp. sensor also responsible for sending the signal to the dash that displays engine temp?

Thanks,

Gards

No that is a diferent sensor. There are three sensors on mine that deal with Temp Stuff. The one mentioned goes to the CIS-E, then there is a single pole one near the water pump that does the gauge, and a three pole one(two poles on one connector and the thrid sitting by itself) that controls the fans. On some that three pole deal is two seperate sensors, one with two poles and one with a single!

I have a similar problem in my 16v to that described in the first post - cold start gives a poor/low idle which improves as the engine warms up.

In fact, the warmer the engine the higher the idle - when over 100 degrees it will sometimes idle at 1400 rpm!!

Ideas?

To follow up.. OVP was the cause of a low idle when cold, high idle when warm.

By the way, ABS light won't always be on if your OVP is failed. Particularly on a car with ASD - there are 2 circuits inside the OVP.