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97 Civic ex - engine speeds up slows down while driving
1st timer here! I have searched and i am not finding anything that seems to be similar to my problem
I have a 97 ex 5spd d16y8 and while driving.. at almost any speed and holding the gas steady, the motor will speed up and slow down, i dont know how to describe it that well but its almost feels and sounds like vtec kicking in and out ( at all rpm ) ..i know thats not whats happening, but seems like the best way to describe it.. i had an IAT code, and replaced the sensor.. didnt help! .....any suggestions!?!?
Re: 97 Civic ex - engine speeds up slows down while driving
Well i just bought the car a week ago. It is stock with an intake, and the exhaust fell off after the cat (im waiting on new exhaust). Higher unknown miles! :/
The car has the codes for o2s, eld, and vss, so i checked the #15 fuse, and sure enough it was blown, but when i replace it the battery light comes on, so i left it out for now! I plan to check the wires on the o2 and harness under manifold, just havent gotten to it, so i guess is the car acting like its hitting in and out of vtec at any rpm a related issue to the 15 fuse blowing?
Will a short there cause the battery light to come on when i put a NEW fuse in.. it doesnt blow it, just the battery light comes on as soon as u put the new fuse in?
Originally Posted by RonJ
The alternator doesn't work with fuse 15 removed or blown.
The short to ground in the fuse 15 circuit is the problem. Fix it.
Re: 97 Civic ex - engine speeds up slows down while driving
Im gonna stop asking the same question, to get the same response, i just dont get how can it not be working? If car has never died.. I literally drive all over!? Im confused! Lol
Re: 97 Civic ex - engine speeds up slows down while driving
Originally Posted by Donnie Martell
Im confused!
^Clearly.
You came here for advice because you have a limited understanding about how your Civic works. Until your knowledge increases, good advice will go over your head.
Re: 97 Civic ex - engine speeds up slows down while driving
Originally Posted by Donnie Martell
Thanks for all your help! I guess it just dont make sense that my alt isnt working but car never dies! :/
If you notice, Ron did not say the alternator is not working. He said it's not working CORRECTLY. There is a difference.
Think of it like this, your shower head in the bathroom, it has build up so is barely flowing water. Is it working? Yes. Is it working correctly? No. Is it working optimally? No.
Re: 97 Civic ex - engine speeds up slows down while driving
Oh thanks for the advise! As im under the car now, i notice the o2 sensor has a little fray and an exposed wire? Could this be the culprit!? Or should i fix that and keep digging in!?
Re: 97 Civic ex - engine speeds up slows down while driving
Originally Posted by Donnie Martell
As im under the car now, i notice the o2 sensor has a little fray and an exposed wire? Could this be the culprit!? Or should i fix that and keep digging in!?
Post a pic. And yes, especially if one of the exposed one is the Blk/Yel hot wire, which gets voltage from fuse 15.
Re: 97 Civic ex - engine speeds up slows down while driving
There should be 4 wires, with two being black. One of the two black wires turns into a Blk/Yel wire at the connector. Trace the wires back to the 4P connector.
Re: 97 Civic ex - engine speeds up slows down while driving
Lol i think im in over my head! That diagram looks like spanish to me! But i fixed that wire, and i checked wires under manifold and no problems there! So im not sure what to do, especially since the fuse doesnt blow.. i disconnected battery and check light came back, plugged fuse 15 in and battery light came right back!
I just learned the previous owner replaced vss, and battery
I also just discovered under the trunk mat an array of stereo wires laying back there most un taped.. ?
Re: 97 Civic ex - engine speeds up slows down while driving
Leave fuse 15 installed to see whether it blows again. If it does, the cluster "battery" light won't turn on at all.
To clear codes from the ECU, remove the 7.5A hood Back Up fuse for 5 minutes. Then reinstall. Run engine, and check for codes. Post the numbers for all codes thrown.