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Discussion Starter #1 (Edited)
Too tired to give the whole story but I came to believe that the fuel distributor in TE #2 with 220k miles was not up to snuff.

Starting was instantaneous and idle was smooth but juat about anything off idle caused the economy gauge to peg red and stay there until I went back to idle. Car bogged horribly and built up speed like a Peugeot 504 diesel. It got better mileage than TE#1 but I believe that was because it was running lean.

So yesterday I pulled the whole airflow meter/fuel distributor and replaced it with the unit off a wrecked 87 300E. I had that one ready to go with a new airflow housing rubber boot and I also installed new idle control motor hoses. That job sucks due to the spring clip holding the inner hose to the intake manifold nipple under the cold start valve.

Went to start up last night as it was getting dark but no go. Starting fluid will make it run but it dies immediately after that is burned.

I hotwired the fuel pump relay and let the pumps run. I cracked the fuel line inlet to the fuel distributor -- fuel spray. Cracked the fuel line out of the distributor (to the pressure regulator) -- fuel spray. Cracked the fitting leading to the cold start valve -- fuel spray.

Cracking each cylinder line fitting did nothing. Should it? I expected fuel to spray from the loosened fittings when the pumps were running. Nope. No change when I pressed down the airflow plate.

I blamed the used fuel distributor and today swapped in another used distributor that came with 88 TE#3, the pine green one. It was removed from the engine that blew up last year about this time. Just finished that job and the results are exactly the same as with the previous part -- no fuel at the cylinder lines.

So anyone out there have firsthand and recent experience with fuel distributor bahavior? With the pumps hotwired should fuel flow from each cylinder line when the fitting is cracked?

What am I missing here? Can't afford to have TE#2 down on Monday morning. If I dont' get some guidance here I'll put the original fuel distributor back in tomorrow. I won't put the original airflow housing back in, just the original fuel distributor.

Any guidance out there??? In almost 20 years experience with these cars I haven't had to venture into this area before.
 

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The key to a properly running CIS system is fuel pressure under various scenarios, so my first question is in regard to your baseline pressure readings. I haven't messed with this injection system in years, but I do remember that it's important to run some system pressure tests before breaking into the injection. In the past I've found that running condition problems can be traced to issues with the fuel pump check valves and the accumulator. Again, pressure tests will assist with these determinations.
 

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press down slightly on the air flow sensor plate, that should squirt gas for sure.

This is just a guess, but its quite possible that the EHA has to be actuated to enable idle fuel flow... the target adjustment of the air flow thingie is such that the modulation is at about 50%... when the engine is started cold, the whole lambda control system is on a 50% duty cycle until the engine and O2 sensor warm up enough to be put under lambda control and fine tune the mixture.
 

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Discussion Starter #4 (Edited)
The key to a properly running CIS system is fuel pressure under various scenarios, so my first question is in regard to your baseline pressure readings. I haven't messed with this injection system in years, but I do remember that it's important to run some system pressure tests before breaking into the injection. In the past I've found that running condition problems can be traced to issues with the fuel pump check valves and the accumulator. Again, pressure tests will assist with these determinations.
Yeah, it's all about the pressures. However, since the car did start and run, I thought I could swap in another fuel distributor, at least to evaluate it. Apparently not.

I did buy the pressure gauge setup a few months ago so I guess I need to hook that up. I tried to do it once but got discouraged by the limited room to work on the fuel distributor. The gauge fittings interfere with the injector tubes. I need to re-evaluate.
 

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Discussion Starter #5
press down slightly on the air flow sensor plate, that should squirt gas for sure.

This is just a guess, but its quite possible that the EHA has to be actuated to enable idle fuel flow... the target adjustment of the air flow thingie is such that the modulation is at about 50%... when the engine is started cold, the whole lambda control system is on a 50% duty cycle until the engine and O2 sensor warm up enough to be put under lambda control and fine tune the mixture.
Pressing down on the airflow plate did nothing (as far as fuel flowing from the injection line fittings) while the pumps were hotwired. Worrisome, I think.

As for the EHA actuation, well, maybe. I don't know enough about the system (but I'm learning fast!) to say one way or another. The only thing I can say for sure is that (on another 124) I've found that you can unplug the EHA while the engine is idling and it keeps idling. That tells me that an unpowered EHA should pass fuel and I should see fuel squirting from the injection line ports when the pump is hotwired.

Who was it that posted pics of a disassembled fuel distributor a while ago? Ps2cho? Real1shepherd? I can't find them using the search function.
 

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3200 to 4800 ohms of resistance between terminals 14 and 18 when the airflow sensor is at rest.

560 to 1060 ohms of resistance from terminals 14 and 17.

The reading should increase to 3760 to 5640 ohms when the plate is at its lowest point.Adjust until this is achieved.

I'm curious if the EHA harness itself is buggered. No signal, no flex of the magnetic reed to allow fuel to come from the lower to the upper part of the fuel distributor/injectors.
 

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Discussion Starter #7
3200 to 4800 ohms of resistance between terminals 14 and 18 when the airflow sensor is at rest.

560 to 1060 ohms of resistance from terminals 14 and 17.

The reading should increase to 3760 to 5640 ohms when the plate is at its lowest point.Adjust until this is achieved.

I'm curious if the EHA harness itself is buggered. No signal, no flex of the magnetic reed to allow fuel to come from the lower to the upper part of the fuel distributor/injectors.
Good info. The airflow assembly currently in the car is from the 1987 wreck. It looks good and the plate deflects smoothly and easily. Rheostat condition is unknown (but will be tested very soon).

As for the EHA harness, a couple of things: 1) the car started and ran until I pulled the airflow housing/fuel distributor. 2) EHA power/no power shouldn't matter when I hotwire the pumps and deflect the airflow plate
 

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Discussion Starter #8
I hooked up my fuel pressure gauge. The instructions that came with it were awful but I *think* i got the connections right.

System pressure was good at 78 psi. When I opened the valve to check differential pressure though the gauge went *up* to 80 psi. Does that make sense?

When I pulled power tothe pumps pressure dropped down to about 40 psi almost instantly and then continued to bleed off.

I'm about to reinstall the orignal fuel distributor and see if she runs...
 

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CIS doesn't use differential fuel pressure regulators. my LH2.x volvos do, they have a vacuum line to the pressure regulator, and the pressure is an offset from the manifold vacuum, so you do the differential thing. the skinny hose out the back of the M103's FPR is just a vent hose so that in case the diagram fails, it doesn't spray pressurized gas all over the engine, instead its sprayed into the intake (via the crankcase ventilation elbow).
 

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Discussion Starter #11
Fuel in/out connections aren't swapped. I don't think it is physically possible.

Did you make the mistake on a RH drive car?
 

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Yep, rhd kit car.
Stripped a 260e and built a plastic kit jeep and remember having issues at the time of initial starting in its new home.
All the bits and pieces went together in the wrong way and eventually I got it right.

Boyd :)
 

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Discussion Starter #13
I got TE#2 running again last night, nearly 2 months after first messing with it. Actually, I *HAD* to get it running because my 19 YO daughter took her Camaro (my CY 2010 project) and the kids went back to school today.

I talked to Larry at CISFlowTech last week and he really helped me to understand what is going on with the KE-Jetronic system. I have loads left to learn but at least I got the basics.

My upper chamber pressure was reading 78 psi (spec is 75 to 81 psi) so that was good. Lower chamber pressure was about 6 psi lower so that was good too. This made me happy becasue I didn't want to mess with the EHA to bring lower chamber pressure into spec.

With the pumps hotwired I cracked each injector fitting on top of the distributor -- no fuel. I pushed down slightly on the airflow meter plate -- no fuel.

At this point it is snowing a bit, the wind is blowing, my back is hurting from leaning over the fender, and it's getting dark. Time for a Hail Mary pass.

Working as quickly as my cold hands would allow I pulled the fuel distributor/fuel pressure regulator/EHA assembly as a unit and swapped in the assembly from the 88TE parts car I bought from Hanno back in November. I did not mess with the airflow housing (with new boot), the idle control valve (with new hoses), or anything else.

As soon as I cranked the engine I knew it was going to start. It did, but stalled, and i had to try again. This time it kept running. There was some lifter noise but the engine idled smoothly and evenly. I revved it slightly a few times and it sounded good. I let it warm up for a few minutes while double checking for dropped tools and leaks. No problem. Then I took it for a test drive and was very relieved to find that it performed quite well.

Later today I'll check the duty cycle and see how that looks.
 

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Congrats Pete on getting yourself out of trouble! Maybe with the car running much better you have eliminated a lot of the potential causes you were considering and can focus on what may be wrong with the two airflow meter/fuel distributor setups you have (the original, and the one you first swapped in). Glad to hear you have this one nailed before the weather got too cold.
 

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Discussion Starter #15
I've been driving TE#2 daily for over a week and can report on its behavior. All is not well. As of Wednesday it started instantaneously and idled very smoothly but the bogging was still there. Strangely, it seemed to be intermittent.

One time you'd put your foot in it and pretty much nothing would happen until you got kickdown. At the next stop sign or stop light it would perform much better.

I had not checked the duty cycle after all my work, largely becasue the adjustment screw was still capped.

I got worried because the exhaust was quite stinky by the time I got my son to school. I do not want to buy cats!

So Thursday I finally got the idle adjustment plug out and hung the duty cycle meter on it. The reading was something like 17% and steady. Wow, no *wonder* the exhaust was stinky!

I adjusted the allen screw until I got about 50% at idle. When i went to retrieve my son I was surprised at how much the car had changed. Zooom!!! Really dramatic. I have yet to do a cold start to see if that was affected.

I have to say that I really don't understand how tweaking that little screw can make such a big difference. All you are doing when you adjust the screw is changing the air flow plate position just the tiniest, tiniest bit. Now I can see how that will affect the mixture at idle but how in the world does that affect mid- to high-RPM behavior?

I really don't get it.
 

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the screw pre-sets the range for the EHA (electro hydraulic actuator) ... when you're reading around 50% at idle, you're right in the middle of the range of lambda control, so that when you open it up and its in high flow conditions, there's plenty of working range so the ECU can modulate the EHA to keep the mixture stochastic without pegging either too rich or too lean.

if you start out too close to one end or the other, when you open it up, there won't be sufficient range to keep things where they belong. too rich will foul the cat, too lean is just bad for the engnie.
 

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Pete, does the fact that it functions as it should make up for that second "inspection" hole in the block that I didn't know about?
 
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