Hello all:

New to the forum...hope i’m properly searching and posting here...did not find solution to my problem (on a repair for a friend’s vehicle), so...


1993 Honda Accord 5-Door, 4-cyl. 2.2L, A/T


Original ISSUE:

Timing Belt Drive Pulley failure (two broken teeth) led to complete timing assembly failure during operation, leading to 6 bent valves.

Head machined (Surfacing/Valve Job). Head reinstalled using top-end gasket kit; Intake Plenum and exhaust components also resealed using included gaskets/o-rings/seals. Valves adjusted to spec. Timing assembly repaired, belts replaced. ALL work done to spec. (according to Haynes).

Engine starts and runs like new...

However, upon intial start, a very loud, steady screeching noise could be heard coming from the front of the engine. Belts were checked, readjusted and the car restarted. Noise continued.

Upon further inspection, the noise was isolated to the alternator. It was shown that unplugging the 3-Pin connector at the back of the alternator caused the noise to cease; when 3-Pin plugged back in, steady noise resumes. All tests of 3-Pin connector power/ground come up PASS.


ALSO:

- During first tries to restart, it was determined that the fuel pump was not getting steady ground and thus the car would not start/stay running without difficulty. It was found that a triple-wire ground beneath the thermostat housing was not secured. The ground was secured and the problem was corrected.

- 80AMP MAIN fuse (#15 to battery, at under hood fuse block) was replaced as it was discovered to have been damaged (blown and without a top glass). Fuse remains in working order, while alt. noise issue remains.

- TCU codes initially showed 1, 2, 7 & 8. after checking harness connections at unit and under hood, and tapping Solenoid Valves A & B under hood, the codes were cleared. Subsequent code checks came up NONE. (Transmission shifts into all available gears.)


DONE:

- ECU & TCU Codes check. After some initial codes, results now consistently NONE.

- MAIN RELAY (under driver’s dash) thoroughly inspected/tested. PASS.

- Charging System Check. System fails Haynes Step #11.1i.1 in Chapter 5 (Engine Electrical) on Page 5-7 (i.e. – test light is ON when between NEGATIVE battery post and disconnected NEGATIVE cable). Pulling fuses (Step #11.2) results in test light OFF when removing fuses #22 (Interior Light) & #24 Back Up (Radio) located in the under hood fuse block. This failure seems to suggest a drain (short) in the circuits, however, to me, this appears to be a non-issue.

- Checked all radio, lighter and center console electrical connections

- Thorough under hood harness connections check

- Fuse block checks (both, all fuses)

- Purchased new alternator and installed. Issue remains. However, at some point during this new part installation, the 80AMP MAIN fuse issue noted above was discovered, and during diagnosis of that issue, the noise ceased when fiddling with the damaged fuse, the new or original alternator installed. But after replacing the fuse and reinstalling the original alternator (which twice tested “Good” at Autozone), the noise returned as before.

- Starter was recently replaced; functions as designed


IN SUMMARY:

There is a loud, steady screeching sound coming from alternator when 3-Pin connector at rear is CONNECTED; noise ceases when 3-Pin connector DISCONNECTED. All primary visual, mechanical and electrical troubleshooting has been conducted with all results coming up PASS (except for Charging System Check concerns noted above); specifically, all tests of 3-Pin connector power/ground come up PASS.

It does not appear to be ECU or TCU related; fuse, power or ground related; belt adjustment related; or a faulty alternator (e.g. - bad bearings).

ANY thoughts? please keep in mind that i have done EVERYTHING by the book, have the car running like new, and know what i’m doing (5th rebuild rodeo)...i’ve explored the common...i’m seeking to resolve what appears to be an extraordinary situation that will likely require the feedback of a highly adept Honda electrical guru.

That said, in the end, it will probably be something simple that is being overlooked...

I appreciate any help in advance...

cheers-
christopher

 

try replacing the alternator?

 

X2 this^^.

 

as i said in the original post, DONE. noise persists.

 

what does this mean?

 

See the arrows? Next time try not to be so long winded. People tend to want to skim over posts like that or skip it altogether. I re-read it and I still do not see that you've identified where the noise is coming from. I don't see how it could be the alternator if two separate units are exhibiting the same behavior. The only time you got the noise to stop was when you "fiddled" (whatever that means) with the 80amp fuse.

 

no, i don't see the arrows. i see the use of the logical conjunction symbol in a non-mathematical equation, alongside "X2" and the word “this.” either way, none of it has anything to do with my post.

forum rules ask me to "BE SPECIFIC" (i.e. - long winded) about my issue. i gave the original issue, repairs made, other potentially related issues occurring during the repair, and a summary of all, so i think i've met that burden in my post. which you should re-re-read. you should also re-read the forum rules..."being an ***” is prohibited.
again, to repeat my original post, upon further inspection, the noise was isolated to the alternator.
i agree. it's not the alternator. you know, like i indicated at least twice in my original post that you read and re-read. that's why i'm on this board at all...because after 4 weeks of thorough troubleshooting, including the installation of both the original and a new alternator, the noise continues when the 3-Pin connector is connected. so, the question appears to be: what electrical issue (besides those already addressed) would cause the alternator to squeal steadily when the 3-Pin connector is connected?
really? as in, "you may have to fiddle with the antenna to get a clear picture on the TV." so, when fiddling with the damaged 80AMP fuse (antenna), the 3-Pin connector CONNECTED, the noise would stop momentarily (clear picture). however, after replacing the damaged fuse entirely, the 3-Pin connector CONNECTED, the noise returned as before. not sure why, but wanted readers to know that as it may be of some relevance to the issue – like all the “ALSO” events in my original post.

for you and others who can’t or don’t like to read, or, can’t function in a world not limited to 140 characters or less, by all means, skip it altogether. i'm sorry that i'm well versed at the keyboard and utilizing the English language.

everyone else: i appreciate your time and could use your constructive help with this issue. thank you, in advance.

 

No need to get nasty about it. Even though your post is detailed it is absolutely convoluted. To the point that no matter how many times you read it you cannot make any sense of it. You want to spit venom at me because I'm trying to follow your logic? Skip the insults because no one here was trying to insult YOU.

I also didn't know you can "fiddle" with a fuse. You either have it plugged in or you do not. It either works or it does not. Your analogy of a TV antenna makes no sense.

Maybe you should get a camera, and shoot some video so we can all make sense of this noise.