Questions about gas mileage and lights flickering, 98 civic LX

No joy..... the ELD connector connection seems solid.....

Also, I found this article which goes into great detail about the dual charging system:

/glenn

If you are ever over this side of the pond John Haynes, the founder of Haynes Manuals, has set up a superb motor museum in Sparkford, Somerset that is well worth a visit.

Folks, I'd like to ask your opinion, particularly yours Tegger.....

Intermittently, the charging system has worked as it is supposed to, in that system voltage rises to 13.5 or so. But, for the most part, it stays between 11.5 and 12.0 depending on load.

So, only a couple of things that could be wrong. ELD, alternator, wiring, computer.

Last night I pulled the intake manifold support per the TSB found on Teggers website. No joy. No bare wires, etc. Everything looks fine.

I ran across an ELD bypass technique put together by an EE trying to get more voltage for his sound system. In short he puts an 820 ohm resistor across the ELD circuit, and tricks the ECU into thinking that there is a load demand and the alternator turns on.

I just put that resistance into my car, eliminating the ELD so that I could determine if the problem is the ELD or alternator, ignoring wiring and ECU possibilities. The ECU saw the 2.1 volts, and the alternator didn't turn on, i.e. my system voltage stayed at 12.0 volts.

So, my question to you is, do you think it makes sense to just change out the alternator, thinking that it just isn't reacting to ECU (computer) signals telling it to go to high output mode? The car has 165K miles, and an earlier reply suggested that over 150K the alternator is suspect. Looking at it when under the car yesterday, it was pretty corroded and nasty looking......

thanks much, /glenn

"/g" wrote in news:vDHqq.46$ snipped-for-privacy@newsreading01.news.tds.net:

you could check the alternator to see if the field circuit is getting more current to create more output current. that's how the alternator regulates it's current output,by changing the field current.Stronger field,more output current(and voltage climbs). a scope would show you if a diode or two is bad and the alternator output missing a phase ot two,that would reduce it's output. the alternator puts out pulsating DC that is smoothed by the battery.

missing a phase or two would show up on the scope.

alternately(pun intended),I believe places like Autozone or Advance Auto can test alternators.Take it off and over to A-Z for test.

Your alternator has six diodes,three for the output coils,and three for the field coils. any one bad diode would reduce output.

you might just have a bad ground somewhere. take a jumper cable and ground the alternator frame to the car chassis.

indeed. most people don't have access to a scope, so it's the best solution - the thing will get a full field test too which is harder to do on the car.

concur.

Ha !!!!!!!! I win !!!!!!!!!!!

Alternator was bad.

Removed old one this morning and took it to Advance. They tested it, so I bought a rebuilt. Just finished putting it in, and a quick startup shows 14.4vdc on the cig lighter meter !!!!!!!

We'll see how it works overall this week.

Funny stat. When I called about price/availability, they told me what they had, and gave me warranty information. If the car is built in Canada, the alternator warranty is void..... I'll bet it's because the canadian cars don't have the ELD and therefore, the alternator runs constantly vs. via the ELD. Kind of dumb considering a normal car doesn't have the ELD and the alternator runs constantly.

Just for fun, I might eventually bypass the ELD and see what effect it has on the gas mileage.

Also, I'll bet that my mileage goes up a bit now because the voltages will be normal and not low. I've seen situations where cars just don't run at full potential due to voltage problems.....

thanks for all the help, /glenn

"/g" wrote in news:vDHqq.46$ snipped-for-privacy@newsreading01.news.tds.net:

Apparently the ELD is not supposed to allow charging voltage below

12.4V, so the's something else at work here.

This guy /really/ seems to know his stuff. I'm impressed.

According to the (excellent) file you referenced in another post, the ELD is never supposed to command a no-charge situation, just a low-charge one (12.4V+). According to that same file, it is possible for the charge light to fail to illuminate if an open exits in the Lamp line in the ELD.

Appearance doesn't tell you much. I'm in the Rust Belt, and we get frightenly awful levels of corrosion on everything -- but everything funcions just fine.

But if you've factored the ELD out of the equation, and have no other odd symptoms that would point to bad wiring, then it is looking increasingly like the alternator is indeed at fault.

Is this an aftermarket reman alternator? Or is it from the factory?

How do the brushes look? Are they really short, with signs of arcing? You should be able to pull the brush holder without removing the alternator.

Jim Yanik wrote in news:Xns9F8CEF8C35C27jyaniklocalnetcom@216.168.3.44:

These are good points.

Plus, in a high-corrosion environment, grounds can get wrecked and disappear and not be noticed until you specifically inspect for them.

only on a handy-dandy denso. others require the casing to be split and special tools - hard to do /off/ the car, let alone on. and it's pretty pointless messing abut with brushes unless you know the slip rings are good and the regulator's good.