What years have the intermittent problem, Dist # ECU#

[kzbill]

Mine is a 1991 festiva L 5 spd

Optical sensor distributor casting number stamped on side w/I.D. #T2T52371 (NO "B")

ECU# B37618881D "D" suffix some will have "A", "B", "C", suffix on end of number I think one will have a ford part number.

I've written to a couple ECU repair places to find out if there was a known Issue with these ECU's and hope to post any answers i get.

[WmWatt]

For info on the ICM in the distribuor look in www.ncf.ca/~ag384/Cars.htm. It's often the cause of intermittent distributor proplems. They can be tested for free at some auto ptrts stores. The bit that usually fails is a capacitor or something costing a few cents but the ICM's are moulded plastic and hard to repair. I took my old one apart to see what's inside. Hope that helps.

[kzbill]

Has a new ICM on it

[kzbill]

first report from the Wizard

This is the report I got from my friend this am. he is checking the whole thing over. and trying to find the intermittant power loss issue.
B6 Stutter

"How about this? I scoped the ignition primary signal and the Hall Effect pick-up coil…..The pick-up had a spike in it that resonated into the ignition system. I cleaned the grounds and the spike is gone. With the clean signal I don’t hear the misfire/popping I was hearing before at higher rpm’s.


It appears the front pulley is mounted in the wrong position. I went through a manual mechanical timing set up this am and made my own TDC mark on the pulley. I then searched through the wires over by the master cylinder and found that the wire that shut the motor down when grounded is actually a pigtail for the coil primary circuit. I found the correct wire and checked timing; it was at 20° advanced. I dropped it down to 10° with the correct wire grounded.


Flashing codes I’ve got them for the VAF sensor and the CKP sensor. The CKP is explained by the spike in the pattern, the VAF I don’t understand. They don’t give an expected value at any PRM so I can only guess that doesn’t matter, only if the signal is missing or there (half full/half empty). The “good Festiva” scope trace has the VAF signal in it. At idle the voltage is about 3.10 volts, I’ve got no noise or signal break down throughout the pattern. Could the sensor have been unplugged with the engine running at some time?

I’ll take it for a test drive this afternoon but seeing it was intermittent I probably won’t feel it’s solved until you put some miles on it."

[25Horseplay]

Good luck! I hope this solves your problems!

[kzbill]

I am only going through this to solve the issue for any of us that has the problem. I have spent so many hours researching this and now calling in favors it is scary, to get this done once and for all. I also spent money foolishly on a few parts but not too foolishly and not too much. I now have a lot of "proven good" parts to catalog and mark.
I just talked to my friend and asked him to write it up for posting the problem with the bad signals and and spikes on the scope seems to be grounds. Not TPS,VAF,ECU,BAT, or any other component. there is a ground he tells me on the thermostat housing that seems to be the main culprit, also the main ground on the transmission was a little dirty too and I just replaced that whole ground wire.

[dahodges]

Can you tell us were these ground wires are on the tstat and transmission?

[kzbill]

The ground wire was on a bracket mounted to the thermostat housing with two black wires on a ring terminal.
I don't think that caused my problems as they are back but they did help the overall tuning.

[kzbill]

Well, I may have phinaly phixed the ph**king phestiva
for all you injected 90-93 phartiva owners with the optical distributor and this problem I will explain.
I was searching the Distributor number T2T52371 all over the web, I found what other cars it fit.
Mazda 323
Mazda Protoge
Kia sephia
Mercury Tracer

Then I went to some help phorums about the Mazda and read. Many places were I at! Somewhere and for the life of me I can't remember where I saw a similar problem described. everyone describes it differently, although lack of power, bad idle and the givaway.......ta da......turn the key off, turn the key back on and it starts and runs ok for a while again.
Seems as though as with mine it gets worse daily. most people replace a Vane airflow meter, and numerous other things as did I.
Someone on the board I was at answered the question with what seemed to make much sense.
He said: On the optical sensor distributor the front seal, between the engine and the front bearing., will leak after a time. When oil gets on the optical diodes or lights or LED's or whatever they are. it goes blind from time to time.
If there is any oil in the Distributor you have a problem. The cure was a new Distributor!
being both cheap and inquisative I decided to take both my distributors apart and make a good one from the two.
Once I get a new bearing and seal I will fix the one that remains.
I disassembled the entire thing all the way to the sensor level. it was soaked with oil. I removed the sensor and cleaned and cleaned it with alcohol and compressed air, about five times.
I took the better of the two distributors, the one without any oil seapage, and put the known good sensor in that one.
I then reassembled it and put it in the car and it ran and so far after twenty miles or so it hasn't quit.
I am going to reserve judgement but I couldn't make two mi. yesterday.
I know I have false alarmed before but now I think it makes sense, dirty optics was one thing I did ask the master technician and he said he had never seen that to be problem. My guess is that positive crankase pressure could push a little oil between the seal and the shaft. A known Problem on other cars that use this distributor.
Gosh I hope I am right but all seems good.

[kzbill]

I had a problem with the Idle air control motor swapped that out and then fixed the distributor.

I installed the new optical sensor now all my ignition problems seem solved even the low speed miss or "pop"