not the average electrical problem... no vtec or iab's on gsr swap
Thread Starter
Honda-Tech Member
Joined: Jan 2003
Posts: 3,156
Likes: 0
From: can't find parking in baltimore
not the average electrical problem... no vtec or iab's on gsr swap
posted in eg+ forum, but didn't get anything...
-the car is a 98 civic dx hatchback (obd2a)
-motor is a 95 jdm gsr (b18c1 basically) obd1 (obd1 dizzy and alternator)
-ecu is a jdm p72 obd2a
SYMPTOMS:
-interior and exterior lights and blower motor noticably dim below 3.5K rpms or 51mph when on the gas
-NO vtec(maybe) but deffinately no IAB operation
-sluggish acceleration and no torque, occasional stumbling throughout the rpm range
-when cold, or restarted and still hot, car is practically inoperable due to stumbling and stalling at anything above ~5% throttle
CONDITIONS:
-usually occurs after engine has been running for quite a while, ie after a trip to or from school or ~1 hour.
-i have noticed that i do have vtec, iab, torque, acceleration and bright lights sometimes as normal after either: (A) letting car cool, but not get cold -or- (B) wiggling wiring at iab soleniod
ADDITIONAL INFO:
i do swaps, i make obd conversions.. this still has me stumped. the wiring is all correct and connections are good and plugs have solid contact. grounds are great and intact.
however i have not tested the alternator, but i strongly believe it is good, as is the battery. and i have driven this car 5+ hours at a time without any glitches except this one. basically, if it wasn't charging or couldn't charge it would've been dead long ago. as well, this is way beyond the slight dim caused by normal voltage regulation in the charging system
in searching, seems other people have had similiar problems, but no real answer has been made. the charging system is my guess, but not mechanical failure.
CHARGING SYSTEM INFO:
the alternator, is internally regulated. also it is externally "regulated" and activated by the computer according to electric load, vehicle speed, engine coolant temperature, accersories and intake air temperature. the computer uses this activation to adjust the amount of voltage generated beyond the voltage regulator's ability, creating less load on the engine. kind of a "smart" charging system.
i believe that the computer is lowering and occasionally eliminating the alternators output voltage. now i just need to know WHY?!?!
so honda-tech gurus... whats the deal here??
-the car is a 98 civic dx hatchback (obd2a)
-motor is a 95 jdm gsr (b18c1 basically) obd1 (obd1 dizzy and alternator)
-ecu is a jdm p72 obd2a
SYMPTOMS:
-interior and exterior lights and blower motor noticably dim below 3.5K rpms or 51mph when on the gas
-NO vtec(maybe) but deffinately no IAB operation
-sluggish acceleration and no torque, occasional stumbling throughout the rpm range
-when cold, or restarted and still hot, car is practically inoperable due to stumbling and stalling at anything above ~5% throttle
CONDITIONS:
-usually occurs after engine has been running for quite a while, ie after a trip to or from school or ~1 hour.
-i have noticed that i do have vtec, iab, torque, acceleration and bright lights sometimes as normal after either: (A) letting car cool, but not get cold -or- (B) wiggling wiring at iab soleniod
ADDITIONAL INFO:
i do swaps, i make obd conversions.. this still has me stumped. the wiring is all correct and connections are good and plugs have solid contact. grounds are great and intact.
however i have not tested the alternator, but i strongly believe it is good, as is the battery. and i have driven this car 5+ hours at a time without any glitches except this one. basically, if it wasn't charging or couldn't charge it would've been dead long ago. as well, this is way beyond the slight dim caused by normal voltage regulation in the charging system
in searching, seems other people have had similiar problems, but no real answer has been made. the charging system is my guess, but not mechanical failure.
CHARGING SYSTEM INFO:
the alternator, is internally regulated. also it is externally "regulated" and activated by the computer according to electric load, vehicle speed, engine coolant temperature, accersories and intake air temperature. the computer uses this activation to adjust the amount of voltage generated beyond the voltage regulator's ability, creating less load on the engine. kind of a "smart" charging system.
i believe that the computer is lowering and occasionally eliminating the alternators output voltage. now i just need to know WHY?!?!
so honda-tech gurus... whats the deal here??
Honda-Tech Member
Joined: Jan 2003
Posts: 8,132
Likes: 5
Re: not the average electrical problem... no vtec or iab's on gsr swap (MonkeyMagic)
Check the alternator 'C' wire for an intermittent short to ground. That's the wire the ECU uses to deactivate the alternator. It doesn't so much control the alternator, but it has the ability to shut it off. The voltage regulator puts about 8.5 volts on that 'C' wire, & the ECU grounds it to deactivate the alternator. So any short to ground would shut off the alternator.
Is it a USDM alternator with a JDM ECU? Maybe that control scheme is different? My Helm book says only US cars have an ELD, but it only covers US & Canada, not Japan. And it doesn't talk about alternator control scheme being different. So I'm kinda guessing about that.
Is it a USDM alternator with a JDM ECU? Maybe that control scheme is different? My Helm book says only US cars have an ELD, but it only covers US & Canada, not Japan. And it doesn't talk about alternator control scheme being different. So I'm kinda guessing about that.
Thread
Thread Starter
Forum
Replies
Last Post
MonkeyMagic
Hybrid / Engine Swaps
3
Apr 5, 2005 09:49 PM
MonkeyMagic
Honda Civic / Del Sol (1992 - 2000)
4
Apr 5, 2005 08:50 AM
