Re: [DML]Lambda ECU not connected(was: K-jetronic not connected)

[Mads de Bruin <debruin@xxxxxxxxxx>]

Because the car was running fine and I drove it only once in the 
meantime, I didn't know what the solution was until this weekend. It 
turned out to be a simple problem.
It seems like the previousowner had a mechanic who probably disconnected 
the Lambda ECU connector and wasn't aware of it (or it was disconnected 
when he bought it, I don't know). He adjusted the O2 accordingly to keep 
the engine at a nice idle (O2 was way too high).
This weekend I was at DMC-Service who did my annual check-up and some 
other work and I ran the problem by him. We connected the Lambda 
connector and when we started it up, it started to idle irregularly. He 
started to adjust the O2 and had it running like it was supposed to in 
seconds.
So I''m glad the Lambda ECU wasn't defective and it was just a question 
of adjusting the O2.
It runs much better now and it responds much better when I press the 
accelarator.
Thank you all for your help and responses.

Mads de Bruin
Netherlands
#02010

[moderator snip]

>
>Mads,
>
>I assume by 'silver box' you are talking about the Lambda ECU.  apparently a 
>previous owner or mechanic had a problem with the lambda/frequency valve 
>system and did not care to repair the problem the right way, leaving you to try to
>
>1) figure out what the original problem was 
>2) figure out how they dealt with it in any number of stupid ways and 
>3) how to fix it the right way (that's where the shop manual and the DML 
>comes in!!!!!!).  
>
>the lambda ECU's function is to take readings from the lambda sensor, 
>interpret them as rich or lean, and instruct the frequency valve to modify the fuel 
>amount by varying its duty cycle in a pulse width signal (the valve is actually 
>kind of an actuator).  
>
>the first problem, even though your car seems to run 'perfectly', is that it 
>idles too high.  750RPM is correct according to the books.  
>
>you have two options - either
>
>1) leave the car as it is in a hacked but running state (like so many other 
>D's out there)
>or
>2) spend some quality time and money getting it to run 'right'.
>
>most of us on the DML would advocate option 2.  begin by plugging in the box 
>and making sure none of the wiring is cut or spliced.  if it is spliced, there 
>is other wiring added or deleted that you need to repair. refer to the 
>electrical diagram and read part 4 under the fuel, emissions chapter of the shop 
>manual.  you should replace your lambda sensor and make sure the frequency valve 
>is buzzing while the car is running, even if it doesn't sound like it is 
>running/idling well.  at least then the ECU isn't dead.  take your throttle linkage 
>apart, clean it, lubricate it, and make sure it is adjusted properly (could 
>be why your idle is high).  also the usual check of all vacuum lines, vacuum 
>leaks, etc could cause high idle.  
>
>this will probably take a while to fix properly but be patient.  the ECU 
>doesn't go bad often but there is probably more than one problem that needs to be 
>fixed.
>
>Let us know how things go and we will help you along.  it took me about 3 
>years of tinkering before i got my engine running 100% perfect.  i had probably 7 
>different things wrong at once and i had to fix one thing in order for 
>another problem to show itself - just be patient and keep at it.  
>
>Andy



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