[Bauk18]

Thanks plinker17722, but with or without air filter makes no difference

 

[Bauk18]

Improvement day!

The whistle was gone two days later and didn't return after a 30km trip, so I call it fixed for the time being at least.

Other then that, I calibrated the AFM pot meter as earlier described in this topic by H.D. Didn't meet the criteria of 20 degrees, so will have to check again when warmer weather has arrived.

Then continued checking DC. After open loop DC ran up to 98%, just like earlier in post 110. In post 111 H.D. indicates 6 possible causes for a 98% DC:
1- the meter
2- the diagnostic coupling
3- the OVP (supply voltage to CIS-ECU)
4- the CIS-ECU
5- the o2 sensor signal
6- an a/f mixture that is lean beyond the Lambda enriching limit.

I checked 1,2,3 and 5, all good. Leaving 4 and 6 as possible cause of which 6 would be the most plausible one as in my case mixture screw and depth screw CP have been tempered with. Therefore, I decided to assume the ECU is good for now and adjust the mixture. As I had only 1mm of play left between the zero and basic position of the AFM, I needed to increase the dept of the CP screw first from 1,45 to a guessed 1,75mm, this increase of depth of 0,30mm yielded an increase of 4,1mm between zero and basic setting on the other en d of the AFM arm.

Note the importance, to note the correct depth of the screw during a FD refurbishment!

Took the car for a drive to warm up and connected a volt meter to the 02 sensor, connected the DC meter and disconnected the EHA. Based on the Volt reading of the 02 sensor I tried to get the basic metering as close as possible to 450mV. A fiddly job as the adjustment are very very fine, a 2mm turn yields a lean to rich condition and the reading is not steady either. I left it, were the reading stayed between 200 and 700mV for +/-5 minutes of idle.

Then reconnected the EHA, plugged the charcoal canister lead, placed the air filter and adjusted the mixture to around a DC of 47%.

I know there are more parameters that can influence combustion and thus influence the DC and that I might have masked something now, but I found if for now more important to have a steady running engine, to be able to enjoy the car from time to time and I'll check the other parameter one by one from here. Starting with spark condition (separate topic) as the engine has during idle a little shake and a surge at 1500rpm whilst cruising.

 

[bereng]

Great great new, happy to hear about it...

 

[liviu165]

Hello everybody!!

Some time ago I asked our esteemed member @H.D. to help us with information about restarting a car with M117 engine and KE-Jetronic, using a refurbished FD. The thread can be found here: M117 Technical Help | C126 Coupes

H.D graciously agreed and sent me a PDF document that I am glad to attach it to this post because it applies to this thread too.

I would also like to use the opportunity to express my satisfaction for the fact that you followed H.D.'s suggested troubleshooting path instead of taking the easy path (but a very wrong one) of meddling with the adjustment screws. Such detailed troubleshooting path makes his efforts worth.

Thank you

 

[Bauk18]

liviu165, thank you very much for sharing, this is indeed very good info in the light of my topic. Also a big thank you to H.D. for sharing his knowledge again!

 

[Danny86MB560]

@liviu165- do you have a copy of the procedure in FSM 07.3-1665 as mentioned in H.D.s "Reinstallation of a refurbished KE-Jetronic FD"

Thank you,

Dan

 

[Danny86MB560]

You just push the AFM plate down with your finger and see how far below its zero position you feel the other end of the AFM lever reach the CP.

THIS little bit of information helped me with reinstalling my FD after being rebuilt/refurbished! After fooling around with it for about two days and countless hours on this forum, I was about ready to call a tow truck and send it to a local indy shop that repaired my AC system last year.

I was afraid to touch the Lambda adjustment screw, mostly because the ball bearing was in place before I sent the unit for refurbishment. So, I took the FD apart to see how it worked, what exactly happened when the screw was turned.

The AFM plate was set, installed the entire assembly back onto the engine, primed it by turning the key to position two three times, and the engine started up and runs better than it ever has since I bought the car last year!

It took awhile to find this post and read through it because of the title. It also took me some time to not be afraid of turning the Lambda adjustment screw. You can't be scared if you expect to survive at the moment of truth.

 

[Danny86MB560]

Hello everybody!!

Some time ago I asked our esteemed member @H.D. to help us with information about restarting a car with M117 engine and KE-Jetronic, using a refurbished FD. The thread can be found here: M117 Technical Help | C126 Coupes

H.D graciously agreed and sent me a PDF document that I am glad to attach it to this post because it applies to this thread too.

I would also like to use the opportunity to express my satisfaction for the fact that you followed H.D.'s suggested troubleshooting path instead of taking the easy path (but a very wrong one) of meddling with the adjustment screws. Such detailed troubleshooting path makes his efforts worth.

Last, but not least, I would like to invite you to visit the C126 forum C126 Coupes when you have time, especially (but not limited to) the How-To section, as applicable to your cars. Although for now we are still a "satellite' of the 500E forum, we are a small but very valuable group of people and you may find some very useful things there applicable to your cars. Many of us there used to be regulars at BW, but due to various reasons we chose to meet there.

Thank you

I tried to click you link and get this error:

 

[douglasday85]

Sooo, after a couple of weeks finally some progress.

After H.D.'s list about other components affecting the Duty Cycle I tested the onces I did not look at yet. 4 out of the 5 were ok, except a vacuum leak around the throttle body. I couldn't pin point the exact leak, so I removed the AFM, ordered a new AFM booth & throttle body gasket, cleaned the throttle body (found a lot of gunk in the vacuum ports) and put everything back to gather. I also replaced all vacuum rubber bits of the air pump, EGR, EZL, to vacuum gage etc.

This morning the engine started right up and idle's around 900 rpm. After a 20 minutes drive a tested the duty cycle with the following results:

Conditions:
Air pump disengaged / evaporation vacuum line plugged

Engine OFF / Engine temp 90°C : 69,5% to 71,9%
Engine OFF / Engine temp 90°C / AFM deflected : 9,5% to 10,5%
Engine OFF / Engine temp 90°C / Full throttle : 19,5% to 20,5%
Engine @ 900 rpm / Engine temp 90°C : 98,3% steady

The first 3 are OK, but the last one not at all. Does a DC of 98% mean that the adjustment is too far off that it is out of EHA reach?

After H.D.'s list about other components affecting the Duty Cycle I tested the onces I did not look at yet. 4 out of the 5 were ok, except a vacuum leak around the throttle body. I couldn't pin point the exact leak, so I removed the AFM, ordered a new AFM booth & throttle body gasket, cleaned the throttle body (found a lot of gunk in the vacuum ports) and put everything back to gather. I also replaced all vacuum rubber bits of the air pump, EGR, EZL, to vacuum gage etc.
Jumping in here to ask: by "replaced all vacuum rubber bits" are we talking about hoses or o-rings or what? I'm about to attempt my first smoke test in my High -Idle continuing drama ('88 560 SEL) and am doing my best to comprehend this advanced discussion. I'd love it, of course, if my issues are solved by cleaning, new AFM booth & Throttle body gasket, etc.
I'm trying to translate what I learned doing this on Volvo 240 to the 560 SEL, inspired by my need to deal with High Idle ongoing issue. Thx, D Day, maine USA