CIS fuel mixture unit question -KE Jetronic

Remove the two small hex head screws marked "Loosen..." in this jpeg -- the microswitch assembly then just pulls off the "D"-shaped shaft (towards the RH side).
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I hope thats not your TR engine Steve.....

 

No, just a photo that someone else previously posted that I used to describe how to adjust the microswitch's rotary position.

(I think it might even be a F113B TR, and not a US TR, because of the extra "nipple" on the throttle body.)

 

1. Can we back up some? Maybe I missed it, but where did you get this TR? Did someone put a gun to your head and force you to take it, or did you find it wandering aimlessly by itself in the wilderness? Really -- please give some background about prior use/abuse/sitting/mileage vs time/etc.

2. In another thread you said "The injectors and distributors are flowing okay", but without really quantifying and/or explaining it - there's more to it than fuel comes out of all of the injectors. Bottom line is that with the airflow plate in about the idle position (maybe 0.5~1.0mm open) you should nominally have 6.8 mL/minute of fuel flowing out of each injector IIRC (fuel pump jumpered to run and EHA current = 0 mA). Disuse is particularly hard on K/KE-Jet due to the many small clearances inside the FD being suspectable to fuel varnish/gunk. But give background -- you seem to be approaching this like re-awakening a perfectly-maintained, and perfectly-running TR, but, if it's been over-molested (like someone trying to rebuild the FDs and giving up), you'd need to get to this level IMO. Similarly, at a wider airflow plate opening (say ~5 mm) you should be getting something like ~40 mL/minute out of each injector. The jpegs below show the factory tool (which measures flow rate directly via rotometers) and the volume measuring vs time set-up that I recently used to calculate flow rate (100mL polysulfone graduated cylinders are available from US Plastics -- and running idle for three minutes gives a reasonable volume of fuel to measure).

3. It is a concern that your tach is not working correctly, and getting some spark is a good sign, but this really requires an oscilloscope and getting to some fairly inaccessible wires. I'll email you the Diagnosis sheet for the MED 120B ignition that allows a lot of test with just a multimeter (but without the "breakout box" some of this isn't easy, and it's written more for a TR that will run at least on one bank -- not something with a lot of other unknowns).

4. As far as testing the EHAs -- you shouldn't even be worrying about those yet. You should presently be doing everything with the O2 sensors unplugged - which sets a default current in the EHAs (~7 mA when warm). Even if the EHA was "dead", as long as it isn't changing its behavior, you should still be able to achieve a good manual tweak at idle (i.e., by using the manual tweak force the 6.8 mL/minute at idle out of each injector regardless of all other sins). If at the good warm idle + O2 sensor unplugged, the current flowing thru the EM was 0 mA, this would indicate something wrong with the EHA or injection ECU. Likewise, at good warm idle + O2 sensor plugged in, the current in the EHA should be varying a few mA around an average value of 7~10 mA as the system runs closed-loop. So measure the current flowing in the EHA coil in the open-loop and closed-loop modes as the test for EHA "wellness".
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OK -- thanks for the background, but it does seem unusual that you had a mechanical problem with the airflow plate mechanism just from storage. Also, if your TR was last tweaked up with the protection relay C not working (i.e., no EHA current), you'll need to untweak for that. Are you trying to locate the KE-Jet section of the TR WSM?

 

The starting point is 1 to 3mm "free play" in the air flow sensor plate. From there you adjust for 8 to 10 ma current draw at the EHA, this is assuming the electronics are working right and your static upper and lower chamber pressures are right.

Larry

 

This isn't/can't be done with the engine running -- this measurement is made when the injectors are removed from the intake manifolds (and the corresponding fuel pump is run by jumpering the fuel pump relay socket 30-to-87).

correct

There's nothing "official" that I'm aware of -- I made up a set of jumper wires using ~4mm (.156") diameter "bullet-style" connectors that allows me to place an ammeter in series with the (running) EHA coil where the stock two-pin molded connector attaches to the EHA (but make super-sure that you keep the polarity correct). The factory recommended way would to use the 25-pin breakout box 95970020 and measure the voltage across the EHA coil at pin 10 and pin 12 IIRC (and do a V= I*R calculation), rather then measuring the current directly. I can't gaurentee this, but the last time I was a Radio Shack, I thought I saw they had the same bullet-style connectors available in about the right size.

With regard to "Is there any rough guide to start adjustments from zero, as in factory new or rebuilt?" -- see the paragraph "Aligning the fuel distributor" at the top of page D33 in the TR WSM. Do that and then confirm that you've got the proper free play in the airflow sensor plate (when pressurized) that Larry F. noted.
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I just stick something (that can't be dropped ) inbetween the rubber "up" stop and the bolt head in the center of the airflow metering plate so that the airflow metering plate is held about in the "idle" position -- maybe 1 mm "open" (i.e., the top of the airflow metering plate is about 1 mm below the cylindrical portion of the air funnel). It's not a super-critical test. You're really looking for equal flow from all injectors at about the nominal idle flow rate rather than trying to hit an exact number -- as long as you are close enough to get the engine running is all you need (and a little rich will run just fine).

 

By sending the whole FD to a qualified rebuilder for complete disassembly/cleaning/reassembly/retest (and flushing out my fuel tank and the rest of the system as best as possible to try to prevent it happening again). Here in the US that person/company is:

Larry Fletcher
CIS Flow Tech LLC
19225 County Road 13
Fairhope, AL 36532
251-929-3771

I don't know of a similar company closer to your location, but maybe Larry might if you give him a call (or you'd have to ship it to him -- which won't be hassle free IME with governments involved ).

Just removing the injector line from the top of the FD to let fuel out at zero pressure won't really do much IMO (although no harm in trying). The small clearances, where a piece of debris can affect the fuel delivery to a single injector, are inside the FD at the slits and the ceramic valve in the upper chambers.

You should always use fresh Copper washers IMO (especially on the fuel stuff), as when fresh, they are fully-annealed (i.e., very soft) so they can deform easily and seal well. Once they are crushed, they strain-harden and won't reseal as well. If you are stuck on a desert island, you can reanneal them by heating them to cherry red and letting them cool, but (since you typically don't have an inert environment available to heat them in) this also oxidizes the surface which isn't so great. Your proximity to Deutschland should make these not so hard to get.

Good Hunting!

 

Larry is definitely the CIS guy! I had some issues with a 308 QV that had me scratching my head and he knew just what to look at.

 

A company in Nurnberg, GE can rebuild your FD. If you want their info I can get it for you. Bosch does not. I tried.


It is VERY, VERY pricey (HIGH Hundreds (EU) to LOW Thousands (EU)) to have it done here in Germany.


I am rebuilding a spare I have for the education. Bosch does not even carry 25% of the required parts. Have to source rubber O-Rings and copper O-Rings from other suppliers. A REAL PITA. The center rubber gasket sealing it all together in UNOBTAINIUM nad must be cleaned and resued. You MIGHT BE Luckier.

And after I am done I will STILL HAVE TO SEND IT to someone (see below) to have it adjusted properly as it is truly amazing how so few parts (<50 and most the exact same: screws, O-rings, etc.) can be sooooooooooooooo micro adjustment sensitive.



My best advice: GO with Larry Fletcher.

Call first. Check his CISTECH website for more info and contact info.



(NO CONNECTION other than both having a German wife and both having a great sense of humor).

 

Thankyou fellas
Your replies are much appreciated.
I will speak firstly to a local bosch expert who repaired my injector pipes and if he cannot help i will speak with Larry.
Best Regards
Clive
P.s off topic-after reading posts re transmission oils, which would you fellas choose for the english climate ? Roughly 16deg ish
TIA

 

Hello. I'm tryng to locate the WSM KE-Jetronic section for an 87 TR, any suggestions to get a copy ?

 

This link:

https://www.dropbox.com/s/18bidr3sgbofytb/Workshop Manual Testarossa Supplement Catalytic Converter D61-D106.pdf?dl=0

should get you a pdf copy of pages D61-D106 of the TR WSM covering the MicroPlex ignition system and KE-Jet with Lambda system of the US version TR.

If you have a euro version KE-Jet without Lambda, there is a separate 95990856 booklet for that (but I don't have it in a scanned format):
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However, it is very similar to the US stuff (just without Lambda/O2 sensors) being a sort of subset.

 

Steve,

Many thanks for this. I have a 91 TR that we have owned for 10 years now. Thankfully the car has run fine. The cats were removed by the previous owner and a custom stainless exhaust installed. This obviously will be a good resource if there is any need to work on the KE Jetronic in the future. I really appreciate your making this available.

Marc Trahan

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