Dancing Around / Up/Down Rider Info Display (RID) Bars

[rbleeker]

To all,

 

I have been having really frustrating problems with my 1994 R1100Rs - as wou may remember my ordeal with the idle screwup / zero = zero.

 

Update is that I've been riding my bike just fine with idle TPS set to 0.600v and it is running pretty well but not perfectly b/c there is something wrong for sure, I notice it esp. at full throttle. I got a used Motronic cpu, changed the fuel pump, still no cigar, the problem remains.

 

I noticed the following distinct issues (1) no idle at 0.380v tps, idle is great at 0.600v idle dies exactly at 0.450v (2) the RID bars dance around up/down all the time, the bars are all screwed up, sometimes the bars go up for fuel level esp. only to come down for long periods of time, it also happens for the temp gauge (3) throttle response is fine except for full throttle it just stops pulling.

 

I am pretty sure now there must be an electrical problem, some kind of low voltage causing the tps voltage to drop to the cpu and bars to dance on the RID?

 

Is there some procedure I can follow to isolate the electrical problem?

 

Thanks to all, you all have been very helpful.

 

Robert.

[Boffin]

For electrical problems on negative ground vehicles the golden rule is to check all ground connections first. The fact that more than one circuit looks to be screwy suggests that one end of the battery ground is less than perfect. remove the connectors and make sure that all bonding surfaces are completely clean. After remaking the connections, protect with either dielectric grease or vaseline - I use the latter as it easier to clean off if needed. Silicone based grease is almost impossible to remove completely.

 

Andy

[rbleeker]

Great, Thanks. I will check the neg. connections starting with the battery. PS, I also put in a new battery to deal with a recent repeated ABS low volt. fault warnings, it cranks great now with no ABS faults. It would be great if the neg. battery connection is the culprit. Will keep you posted. Robert

[rbleeker]

To all,

 

I went ahead and cleaned off the neg. connection to the battery and that improved things quite a bit - thanks for the suggestion! The RID Bars are now stable!!!

 

Turns out that I had re-attached the negative wire on the other side of the battery terminal - basically a dirty connector. The connector needed cleaning up.

 

I still have trouble idling when I set the TPS to 0.380v, it just won't do it.. When I set TPS around 0.600v it runs really quite well - balanced throttles, etc - 1100RPM. I tested the CPU = fine, got a new battery, changed fuel pump, fuel filter, etc. Other people have suggested that maybe a bad neg. (or bad connection/wire) on the TPS may cause a lower voltage to get to the CPU, explains why I have to increase it 50%?

 

Does anyone know where the "main" ground points are on the R1100RS (94) bike? Especially the neg. connect on the frame? I wanted to clean them but am having trouble finding them. The wiring diagram tells me they exist, just can't locate them.

 

Maybe after cleaning those neg. connections the TPS voltage will behave better?

 

Thanks for any pointers!

 

Robert.

[DavidEBSmith]

If it runs fine with the TPS voltage at the "incorrect" value of .600, but it runs poorly with the TPS voltage at the "correct" value of .380, maybe you might consider leaving the TPS at the "incorrect" voltage? All the TPS voltage does is tell the Motronic where the throttle is positioned, and if, for whatever reason, the Motronic is reacting correctly to the throttle position, I'd take it and run.

[rbleeker]

I would leave it alone, except the bike won't pull through higher 4-6k rpms as it used to. Full throttle response is terrible with lots of hesitation and dead spots all over the place.

 

I am pretty sure a voltage degradation from the TPS to the CPU is causing this. Again, I am wondering if someone can tell where I can find the ground connection to the frame?