"EPC Circuit for Code 98!"


djhitz

djhitz

15+ Year Member

Joined
Mar 18, 2009
Messages
36
Points
3,101
City
Fort Wayne, IN
Vehicle Year
2-1987's
Transmission
Automatic
B2ers,
My '87 2.9l, EFI, AT, blue B2 has an occasional acceleration hesitation. Snap On's diagnostic brought up two codes. Code 63 which I replaced is the "throttle position sensor" that improved it's starting.
I'm stumped by the second code. It's Code 98, EPC circuit? Does anybody know what the EPC circuit is? I think... it's the circuit box next to the intake but I'm not sure.
I would love, your inputs.
Thank, Dan
 
EPC is one of two (IIRC) shift solenoids in the transmission. You have to pull the valve body to replace it (again, IIRC.) If it is bad, that could definitely be part or all of your hesitation issue.
 
EPC (IIRC), Search:"

Thanks Shran,
First, I'll try to find, the circuit and then I'll see about removing, the valve body to install it.
I see, you have, a rock crawler! Very impressive. I'm sure, you've run into various, pain, transmission problems from time to time.
Rapid City, eh? I ate with a doctor and nurse of the local hospital and my wife for lunch at the Subway, there on my way to Hot Springs, SD to a muscle car show and then onto Capser, WY and then Yellowstone, Tetons, Montana and Idaho. That was, '06 when I could still barely afford to travel.
I met an old photographer, man at Mount Rushmore who was a, WWII, bombardier photographer. Neat guy. Great place.
The gate man was from La Porte, IN, though.
 
Ha!, yeah, I've had bad luck with the last few automatics I've had. Keep burning them up. Although I've gone through a few clutches too.

Yup, I'm actually from Hot Springs. Nice town but not many jobs there so I moved during college. Lots of interesting people in the area as I'm sure you noticed.
 
EPC isn't a shift solenoid. It's the Electronic Pressure Control. It has little to do with shifting per se. It simply controls the amount of fluid pressure available for shifting.
 
"Sound Man, speaketh of EPC!"

"The EPC circuit is still in the tranny, valve body like, Shrad said? Right. Sound Man?"
 
Yeah, it's still part of the transmission valve body, but it isn't a shift solenoid.
 
"I aquired, an EPC circuit from a, local transmission shop run by a friend of mine. It was the wrong one. The one they gave me was much bigger. The one in my trans is smaller and has a bracket, tack welded to it. Back to the shop."
 
"Bad Modulator Valve."

Guess what guys? Shrad and Sound Man, I found, TWO, wrong sized, EPC Circuits:annoyed: and never tried to install them. We tried something different. My transmissions rebuilding, friend gave me a brand new, modulator valve. Rather than dropping out, the valve body to change the EPC circuit (which is how this trans is designed). We just cleaned, the filter up a little. Resealed the pan and filled the case with new fluid and put on the new moduator. It runs and shifts, right. I don't know why the ABS scanned the EPC circuit as, the problem code 98. Perhaps the fact that too much pressure was being built up in the case was deregulating, EPC's pressure cycle. Anyway, I'm majorly relieved:yahoo:. I can go onto other things without having to obsess with my little, B2:headbang:.
 
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Sweet, glad to hear you got it fixed. Sometimes (often) codes will pop up saying "xyz malfunction" when it's really something else causing xyz to malfunction. Sounds like this is one of those cases.
 
djhitz said:
Guess what guys? Shrad and Sound Man. I found, TWO, wrong sized, EPC Circuits:annoyed: and never tried to install them. We tried something different. My transmissions rebuilding, friend gave me a brand new, modulator valve. Rather than dropping out, the valve body to change the EPC circuit (which is how this trans is designed). We just cleaned, the filter up a little. Resealed the pan and filled the case with new fluid and put on the new moduator. It runs and shifts, right. I don't know why the ABS scanned the EPC circuit as, the problem code 98.Perhaps the fact that too much pressure was being built up in the case was deregulating, EPC's pressure cycle. Anyway, I'm majorly relieved:yahoo:. I can go onto other things without having to obsess with my little, B2:headbang:.
Click to expand...

Your punctuation is horrible. You frequently put comas where they do not belong and almost as frequently use a period where you should have a coma. Please return to high school, directly to high school. Do not pass go, do not collect $200.
 
"Too many, "Comas."

Sound Man,
Do "comas" bother you?
I've been writing for a long time and my cousin, the creative writing, professor at JMU says my, sentences have, power. The fact that I'm on Ranger Station/Bronco II Corral means, I have, Ford power.
If you recall, 5th grade grammar. One is to put a, "comma" after every noun before a, direct object unless it's before or after a prepostion.
Besides when does, spelling, punctuation and grammar mean anything on the internet?
I'll consider, your suggestion the next time, I go into 'comas', Sound Man (ADSM08) not Jim.
Please, gimme a break. I fixed, my B2. I'm almost going into a 'coma'.
 
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"Modulator Pressure in trans case was too high."

Shran,
Thanks for your assistance (you too Sound Man). I always appreciate the help and advice I get on the Ranger Station/Bronco II Corral!
 
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