In Brief, I need help figuring out why my 1991 Honda Accord EX doesn’t start and if my diagnosis(s) are accurate and how to troubleshoot the issues at hand.

In Detail,
My 1991 Honda Accord EX started to show difficulty turning over, high RPM at start, poor fuel economy, sputtering, and difficulty holding a stable idle (low RPMs around 200-500).

During the summer, running errands was easy until turning the car off the fourth time, it would crank but not start. to get through this hurdle, I had to wait to give the car a chance to charge up and turn over, or disconnect and reconnect the battery which has given me luck several times when this issue presented itself.

Immediately after this quick fix the car would go through a series of issues ie. (sputtering, and difficulty holding a stable idle (low RPMs around 200-500)

I troubleshot the high idle valve and RPM stabilized, but after running the car for daily use, the issues came back. so I figured this wasn’t a combustion/air intake issue as I cleaned the Throttle Body and EGR Valve and used carbon cleaners.

I focused on this being an electrical issue, and began digging into anything electrically accessible such as battery, alternator, distributor and it’s guts such as ignition coil, ignition control module, spark plugs and wires, fuses, main relay, and wire connections to test for voltage.

The results..?
I replaced the battery to OEM specs as the previous battery was too overpowered which could’ve caused electrical damage, alternator to resolve charging issues(no outcome) distributor, and tested certain components as such.

during these repairs, the car would solely turn on at night or during cooler conditions, till it was only failure to turn over, to a simple click then immediately dashboard lights dimming with very little clarity as well as anything turned on at the time of cranking. it can’t possibly be the starter as mentioned before these components worked perfectly fine and well during stress. Positive terminal would then become uncomfortably hot so I have stopped all diagnostics and focused on ground harnesses to see if after EVERYTHING, the car would return to its original condition, with no positive outcome.

[img alt="To determine if the main relay works, allegedly two audible clicks must be heard when the key is turned. in my case it does click twice.

#2 shows no voltage
I decided to re-solder most of the connectors including #7 which is the connection to the fuel pump"]https://cimg2.ibsrv.net/gimg/honda-tech.com-vbulletin/2000x1504/img_2032_d90054e3909b810d741156fc671b561b4ed393d4. jpeg[/img]
To determine if the main relay works, allegedly two audible clicks must be heard when the key is turned. in my case it does click twice. #2 shows no voltage I decided to re-solder most of the connectors including #7 which is the connection to the fuel pump

during my diagnostic, I found this connection at the engine bay fuse box which I assume is the “main wire harness connector” and due to its condition it can be considered shot or can be re-wired from here to allow a ground voltage to be received to the main relay.

the steps I followed to diagnose the main relay/harness.

the steps I followed to diagnose the fuel pump.

Anything Helps, Thanks!

 

With this being a power distribution issue. I would definitely be looking at the main fuse relay box under the hood as this is where the power gets distributed to the other parts of the car. For me the clicking and hot wires tell me that as you looked into a faulty ground or poor connection.

*Often I would suggest using jumper cables and connect the ground battery post to the engine (near power steering pump is a good place) for a diagnosis to see if this solves the issue.

*A couple of thing that I would still look into is the battery terminal. It could be corroded and not fully connected/crimped near the battery.You can soak them in a cup of baking soda/water, but replacing the cable/terminal end may be a better solution.Possibly even cutting back the cable by an inch or so if it is overly corroded.
Is the alternator for sure putting out the voltage required to run? If the battery can't charge due to low voltage, the car can crank over and not start. When this happens, you can use a battery charger or jumper cables and if it fires right up, low voltage is the issue. You can get the battery load tested probably where you purchased it or any auto parts store to help check voltage, or simply use a volt meter to ensure it is over 12V. If it is close to 10V the car will have issues starting. This is also where a new vs remanned alternator can be an issue if it is a low voltage problem.

*The "your battery is too big for the car" is not applicable with these Hondas that have large enough alternators. This saying started in the 1990's-2010's when they were producing cars with tiny alternators (Subaru's/ford tempos etc) that were just big enough to run the system. I run 750-900 CCA truck batteries in my 89-93 Accords for the last 20 years with no issues. With a brand new car that has more electronics, I would run the stock sized battery, but not in an old car.