Trouble idle and full load on 2.5-16 (ROW)
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W201 2.3-16 // 2.5-16
Hi,
Thanks for explanation and picture.
I will made also my own because very simple to do it.
I come back tomorrow to let you know the results.
Cheers
Thanks for explanation and picture.
I will made also my own because very simple to do it.
I come back tomorrow to let you know the results.
Cheers
Last edited by Vade; May 3, 2023 at 11:33 AM.
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Let is know what you find out!
Last edited by dolucasi; May 3, 2023 at 08:57 PM.
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1991 190E 2.3
Hello,
All the rubber lines are new. It's the reaser why we don't suspect a vacuum leak.
Sorry but I don't understand this last sentence "Have you checked all of the figures for your 190 that is working properly and how do they compare to the problem 190"?
Thanks in advance
All the rubber lines are new. It's the reaser why we don't suspect a vacuum leak.
Sorry but I don't understand this last sentence "Have you checked all of the figures for your 190 that is working properly and how do they compare to the problem 190"?
Thanks in advance
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W201 2.3-16 // 2.5-16
You said previously that you have another 190E 2.5-16v that is running properly. Run the same tests on this car as you've been running on the 190 that you're having the problem with to see how the test figures from the 2 different cars compare. Seeing where the 2 cars test results differ can help to identify where the problem might be.
So, we made the comparaison (essentially an ECU change between the two cars, maybe also OVP relay).
First, I was reticent on test a sure good ECU on a probably "bad car" (afraid about it damage the good ECU).
@dolucasi said no risk to damage it.
And about the EHA from the second car (good one), he was slighty modified (for track use). So, not ideal to test with this one
thanks
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W201 2.3-16 // 2.5-16
Hi guys,
We have checked the EHA and there is 50mA at ingnition on/motor off.
At idle, oscillating between 2,2 and 3,5mA.
So, this part seems to be good (same value as 2.3-16).
I think we've checked all the electronic parts (EHA, IACV, OVP relay, temperature sensor, MAF, microswitch fuel off and throttle sensor).
There is only left the ECU in electronic we'll test tomorrow.
Any other suggestion?
We have checked the EHA and there is 50mA at ingnition on/motor off.
At idle, oscillating between 2,2 and 3,5mA.
So, this part seems to be good (same value as 2.3-16).
I think we've checked all the electronic parts (EHA, IACV, OVP relay, temperature sensor, MAF, microswitch fuel off and throttle sensor).
There is only left the ECU in electronic we'll test tomorrow.
Any other suggestion?
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
I assume the engine was cold when you measured the 50mA but the EAH current is a strong function of coolant temp before it reaches operating temp. Assuming you did not miss a minus sign before 2.2 and 3.5 mA your fuel mixture is set just a bit lean meaning the ECU is having to enrich it. But that will not effect idle. This means it runs a tiny but lean during warm up but again should not cause the knock you were concerned with. If you think about it does it really matter if the ECU is driving 50mA or 47mA during warm up.
Assuming your O2 sensor is in working order, like I suspected the emissions control (air-fuel ratio) loop is working fine.
Ideally you want -2mA to 0mA oscillations but do not adjust that unless you are also measuring fuel pressure.
This being said though, you should measure your fuel pressures as well for completeness sake.
I think you had said the engine appears to be starved for fuel at higher RPM's. For that you would have to route the EHA current into the car and observe when you punch it to higher rpm's.
And do let us know what happens with the new ECU. And it would be good to know your timing numbers at various rpm's. That can also effect running condition at high rpm. You can look up the expected numbers for your model.
Assuming your O2 sensor is in working order, like I suspected the emissions control (air-fuel ratio) loop is working fine.
Ideally you want -2mA to 0mA oscillations but do not adjust that unless you are also measuring fuel pressure.
This being said though, you should measure your fuel pressures as well for completeness sake.
I think you had said the engine appears to be starved for fuel at higher RPM's. For that you would have to route the EHA current into the car and observe when you punch it to higher rpm's.
And do let us know what happens with the new ECU. And it would be good to know your timing numbers at various rpm's. That can also effect running condition at high rpm. You can look up the expected numbers for your model.
Last edited by dolucasi; May 7, 2023 at 02:51 AM.
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W201 2.3-16 // 2.5-16
Yes, exact, motor was cold.
I propose to do the same test (motor off and at idle) but at operating temp.
We'll do also a driving test to see how is the EHA value with full open throttle.
About fuel pressure test, we need to buy a special part/connexion because the space/area is very small.
Tomorrow, we'll test the other ECU.
About timing (it's the only thing we haven't already controlled), we have to buy the tool lamp.
I'll let you know soon about the ECU swap and the EHA readings.
Cheers
I propose to do the same test (motor off and at idle) but at operating temp.
We'll do also a driving test to see how is the EHA value with full open throttle.
About fuel pressure test, we need to buy a special part/connexion because the space/area is very small.
Tomorrow, we'll test the other ECU.
About timing (it's the only thing we haven't already controlled), we have to buy the tool lamp.
I'll let you know soon about the ECU swap and the EHA readings.
Cheers
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MBWorld Fanatic!
Joined: Mar 2016
Posts: 1,369
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Confused. In post #30 you said EHA current is oscillating between 2mA - 3mA.
Now you are saying 8,16mA.
Can you specify these numbers at the temperature you are measuring them?
I'm assuming the EHA current started at 16mA upon cold start-up and drifted towards 8 mA and at full operating temp it started cycling between 2-3mA. Please confirm this.
BTW giving it more thought unless 16V engines are that different, EHA current with ignition on - engine off should always be 20mA (no matter the temperature),
So 50mA does not sound right.
- Cheers!
Now you are saying 8,16mA.
Can you specify these numbers at the temperature you are measuring them?
I'm assuming the EHA current started at 16mA upon cold start-up and drifted towards 8 mA and at full operating temp it started cycling between 2-3mA. Please confirm this.
BTW giving it more thought unless 16V engines are that different, EHA current with ignition on - engine off should always be 20mA (no matter the temperature),
So 50mA does not sound right.
- Cheers!
Thread Starter
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Joined: Apr 2023
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W201 2.3-16 // 2.5-16
Confused. In post #30 you said EHA current is oscillating between 2mA - 3mA.
Now you are saying 8,16mA.
Can you specify these numbers at the temperature you are measuring them?
I'm assuming the EHA current started at 16mA upon cold start-up and drifted towards 8 mA and at full operating temp it started cycling between 2-3mA. Please confirm this.
BTW giving it more thought unless 16V engines are that different, EHA current with ignition on - engine off should always be 20mA (no matter the temperature),
So 50mA does not sound right.
- Cheers!
Now you are saying 8,16mA.
Can you specify these numbers at the temperature you are measuring them?
I'm assuming the EHA current started at 16mA upon cold start-up and drifted towards 8 mA and at full operating temp it started cycling between 2-3mA. Please confirm this.
BTW giving it more thought unless 16V engines are that different, EHA current with ignition on - engine off should always be 20mA (no matter the temperature),
So 50mA does not sound right.
- Cheers!
Sorry to make to some confusion in your mind but values has been taken by my father.
So, the news of today.
Following the values of the 2.5-16 (see the sheet in french), the EHA is functionning good.
Normally, just have to make the test in WOT mode but rainy day today.
The other test of the day is about the O² sensor....
Reporting the duty cycle is at 50% -> "replace the 0² sensor".
When I take the resistance, i'm at 2,6 ohms (normally between 4 to 7).
When test the DC volts, it's very very low to go up/down (0,1v to 0,4 takes 15 seconds and needs average same time or more to go to 0v if I have turned off motor).
Is it normal because, for me, this 0² sensor is failed.
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190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
I can not speak French but I can understand most of what is on that table. And yes your engine seems to be 50mA in that ignition on engine off condition. So no issue there.
If the O2 sensor has more than 60K miles on it just replace it. They do not last that long. Its output does not seem correct. It should be 0.8V +/- 0.45V or something close to that.
When the car is new, they last about 90K miles, with an older engine that will have some amount of oil burning 60K miles is probably a good replacement period depending on the engine.
I can also see that the WOT enrichment is more on your engine than a 2.6L 12V engine. Mine is only 2-3 mA. Yours is more.
- Cheers!
If the O2 sensor has more than 60K miles on it just replace it. They do not last that long. Its output does not seem correct. It should be 0.8V +/- 0.45V or something close to that.
When the car is new, they last about 90K miles, with an older engine that will have some amount of oil burning 60K miles is probably a good replacement period depending on the engine.
I can also see that the WOT enrichment is more on your engine than a 2.6L 12V engine. Mine is only 2-3 mA. Yours is more.
- Cheers!
Last edited by dolucasi; May 8, 2023 at 11:50 AM.
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W201 2.3-16 // 2.5-16
Thanks for your feedback.
We’ll buy tomorrow a new o2 sensor.
After that, we’ll made a short test to be sure about the enrichment in WOT (Cfr EHA value).
Hope we get fix this soon, thanks.
We’ll buy tomorrow a new o2 sensor.
After that, we’ll made a short test to be sure about the enrichment in WOT (Cfr EHA value).
Hope we get fix this soon, thanks.
MBWorld Fanatic!
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Also, make sure the WOT signal goes active by measuring resistance. I tested it for the first time a couple years back and from non-activation for so many years it was not making contact due to corrasion. I activated it many times and sure enough, it started working again. I can see it with my meter in the car, not that I push the car that hard, only to test it.
And non working WOT, will not cause any running issues BTW, it's affect, even at activation is not that noticeable.
And non working WOT, will not cause any running issues BTW, it's affect, even at activation is not that noticeable.
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1991 190E 2.3
Normally, we have to do it last Sunday but I was busy to drive with the other 2.5.
So, we made the comparaison (essentially an ECU change between the two cars, maybe also OVP relay).
First, I was reticent on test a sure good ECU on a probably "bad car" (afraid about it damage the good ECU).
@dolucasi said no risk to damage it.
And about the EHA from the second car (good one), he was slighty modified (for track use). So, not ideal to test with this one
thanks
So, we made the comparaison (essentially an ECU change between the two cars, maybe also OVP relay).
First, I was reticent on test a sure good ECU on a probably "bad car" (afraid about it damage the good ECU).
@dolucasi said no risk to damage it.
And about the EHA from the second car (good one), he was slighty modified (for track use). So, not ideal to test with this one
thanks
Thread Starter
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Joined: Apr 2023
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W201 2.3-16 // 2.5-16
Also, make sure the WOT signal goes active by measuring resistance. I tested it for the first time a couple years back and from non-activation for so many years it was not making contact due to corrasion. I activated it many times and sure enough, it started working again. I can see it with my meter in the car, not that I push the car that hard, only to test it..
But I would like to see how it affects the DC volts at the EHA.
Certainly a test at the end of this week
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W201 2.3-16 // 2.5-16
MBWorld Fanatic!
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Great! I know you meant DC-current not DC-voltage at the EHA, but just wanted to correct that for other eyes.
MBWorld Fanatic!
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Look at your EHA current above 4000rpm while driving, I doubt you will not see anything special like cutting off. Let us know what you find out.
You need to acquire a $20 strobe light and see what your timing is doing at those high RPM's. If the engine is mechanically sound (which you already stated) you will most likely find timing issues at high RPM's.
Cheers!
Thread Starter
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W201 2.3-16 // 2.5-16
Thread Starter
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W201 2.3-16 // 2.5-16
I probably mentioned this before but that is not due to WOT. WOT is designed in to increase the fuel enrichment beyond optimum in those rarest moments when you are passing a car and such when all out acceleration is needed and not tied to any high end RPM's.
Look at your EHA current above 4000rpm while driving, I doubt you will not see anything special like cutting off. Let us know what you find out.
You need to acquire a $20 strobe light and see what your timing is doing at those high RPM's. If the engine is mechanically sound (which you already stated) you will most likely find timing issues at high RPM's.
Cheers!
Look at your EHA current above 4000rpm while driving, I doubt you will not see anything special like cutting off. Let us know what you find out.
You need to acquire a $20 strobe light and see what your timing is doing at those high RPM's. If the engine is mechanically sound (which you already stated) you will most likely find timing issues at high RPM's.
Cheers!
Right about the strobe light, must buy one and test at different RPM.
Cheers
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1991 190E 2.3
The process of elimination is a pain but it's really the best way to identify the specific cause of the problem. It's possible that a previous owner might've messed with the timing in some way. MB makes it pretty tough to adjust the timing but it's not impossible. See what happens first after the new O2 sensor is installed before you do any more testing.
