1991EX

My son is away at boot camp and I am driving his 96 Accord (4 cyl, VTEC, auto)occasionally while he is gone. Had a no start issue so I changed the main relay under the dash. seemed fine for about a month, then no start again (car was cold). Went to troubleshoot 2 days later (look at check engine light etc.) and it started right up. Changed the ignition coil just in case and it ran fine for another 2 weeks, then would not start (cold) again.

Any ideas? It does not seem to hesitate or lose power when warm and the no start condition is after sitting overnight. I hate intermittent problems ( makes you want to drive it.......then get stranded) and am hoping that someone can lead me in the right direction.

phootbag

Can you give more information with regards to the time after the no-start and leading up to the time it actually starts?

Is there anything special you do? Is there anything special about the weather? Raining? Does the environment warm up and get dry and the car starts? etc....

1991EX

I have not noticed any specific weather. One time it was only sitting overnight, the next time it was sitting for about 10 days. It would spin over like it was not getting any fire/fuel etc. This was even after I changed the main relay and coil. Then 2 days or so later I go out and it cranks right away. At least 1/2 full of fuel each time. Have not had it happen again to be able to troubleshoot.

I thought about changing the relay again, but they usually act up when the car is hot.

Is there anything specific to look for if it is related to moisture?

phootbag

First, I hate intermittent faults, too! lol. Sometimes I tell customers, "I wish your car was broken!" And, we USUALLY have a quick laugh.

You need to have diagnostic equipment hooked up. That way when the car doesn't start you can immediately collect data. You need to find out of the problem is a loss of fuel or a loss of spark. Air, timing and compression are very low on the list at this point due to the intermittent nature of the condition.

The data I would want is, fuel pump operation, fuel injector operation, ignition operation ( voltage data for ignition control circuit, primarily ).

poorman212

To phootbag's point the data would be the key. To your question about moisture, yes there are a number of things......cap gasket, ect.

MAD_MIKE

1991EX check your battery connections, and check or have the battery voltage checked. If you can have it load tested as well that would be best.

phootbag would you happen to know if Accords, or Hondas for that matter, will not attempt to start the car(intentionally) if while during cranking the voltage from the battery falls below a set value? I know older Jaguar ECMs will not allow the fuel pump to run if it sees battery voltage drop below a certain voltage while cranking.

phootbag

Honda does not engineer that feature into their vehicles. Low voltage may, as a side-effect, cause things like relays to fail to operate resulting in no-starts, but no intentionally.

MAD_MIKE

Thank you for clarifying.

phootbag

You're welcome.

1991EX

Thought it was fixed and it just started it again. Check engine light seems to be connected to this issue. If the relay clicks and the engine light stays on....no start. If the relay clicks and the engine light goes out it starts right up.

As mentioned, I already changed the relay inder the dash and the coil. Any ideas?

1991EX

Can anyone give me a good vendor to order a factory ECU? I will probably end up changing everything possible. My son will be coming home from the Marines to get this car and I need it dependable.

Any assistance will be greatly appreciated.

1991EX

Another attempt here. I bought a OBDII scanner (CP9580) and hooked it up to the car. When the check engine light stays on the scanner will not diagnose anything. When the check engine light goes out after numerous key turns(car will start, everything is fine) the scanner comes back showing everything is good.

What would cause the scanner not to read when check engine light is staying lit.....relay, ecu?

tsdneil

have you checked the ignition switch or the ignition module?

my car is doing the same thing right now. i know its not the coil because its been replaced recently, its not the ignition switch because that has also been cleaned recently. its hot in here in georgia (95* right now), so it could be the temperature/humidity degrading the soldering joints in the ecu. just another thing to add to the to do list :p

1991EX

I have checked the ignition switch, replaced the coil, ecu fuse, main relay. I purchased the OBDII scanner to attempt to quit throwing parts at it, but when it fails the scanner will not read. I have seen ECU's fail, but never intermittently like this. It is a very nice 96 for my son, lowered with nice springs and koni yellows, nice rims/tires, sound system etc. I guess my next purchase will be an ECU if I cannot figure this out.

Makes no sense to take it to a shop when they will not be able to read codes either.

Thanks for the reply! Know of any good ECU vendors?

phootbag

A shop can do more than tell you it isn't communicating. They can do input tests when the symptom occurs to determine if the problem is a power/ground issue or a problem with the ECU. You need a wiring diagram to perform an input test, which is your next step if you don't want to keep throwing parts at the car.

Being intermittent, if the problem isn't within the ECU itself would probably be a bad connection, ie poor pin fit, loose ground etc.

1991EX

Thanks, the input test makes sense. Only issue is getting it to fail once I am at a shop. I was hoping that the scanner not being able to read the ECU when the CEL is on would help me isolate the issue. Scanner gets power, just cannot analyze.

If I did not own several vehicles I would return the scanner and just buy an ECU. My next step will be inspecting/cleaning all of the grounds.

bvpe

I have a 10th anniv Accord (1993). When cold, it will run for 5 min or so then stall. The CEL will come on and stay on preventing it from starting. After 10 min or so the CEL will go out and the car will run like a top the rest of the day. Unless its is parked for 6 hours or so. I have the service manual and jumped the service check connector and get a MIL 15 which is ignition input signal. I have replaced the ECT sensor after trouble shooting it through the service manual flowchart. This worked for several weeks, now it is acting up again. I see many folks saying to replace the main relay, or have it resoldered. The service manual does not even refer to this for a MIL 15 reading. Any ideas.

1991EX

My suggestion would be to change the relay. 57.00 at NAPA. I have a 91 that was doing the same thing except no codes....changed the relay and it fixed it. Have you changed the coil, cap etc.?

My 96 will run great once started. When the CEL stays on, it will not start and the scanner will not read the ECU codes. When the CEL goes out, the scanner says everything is fine. I am eventually going to buy a new upgraded ECU just to eliminate it. I cannot afford to send my son off across the country in a car that is not dependable.

bvpe

I put a remanufactured distributor with a new cap very early on. I suppose a replacement to the main relay would still be cheaper than taking the car in to a dealer. I'm afraid to take the car anywhere but the dealer thinking that the dealer would have the best equipment to figure this out.

bvpe

Okay, just got done putting in a new main relay. Same problems, no difference. The car was sitting all day, first started around 2:30, temp around 85. it ran for 4 minutes then CEL came on as it died. I tried for twenty minutes, repeatedly turning key on and off to see if CEL would go out (indicating that it is ready to start). Once in a while CEL would go out and I could start the car, but it would only run for 5 seconds sometimes, 30 seconds other times. After twenty minutes it finally started and stayed running. I let it idle for ten minutes and drove it around the block (mile or so). No problems. I can shut it off and it will start right back up. I'm going to park it for the rest of the day and see what it does in the morning .

1991EX

Just an update for anyone having a similar problem. Since I could not get any readings with an OBDII scanner while the CEL was on (scanner would not read at all, gave me a failure message), and when the CEL light would go off the scanner would read fine and no codes were present. Car would start and run fine as long as the CEL light went off initially, but would not start at all if CEL light stayed on.

Changed main relay (twice as a matter of fact)
Checked all battery connections, charge, cleaned all grounding points etc
Changed coil
checked/cleaned ignition switch

Finally ordered a used ECM from epay. Found one with the same numbers etc. and the car started right up and has not failed (yet). I also noticed that the CEL goes out right away now, where before it was slow to go out.

Hope this helps anyone with a similar issue. Took the cover off of the old ECU and it looks brand new, no burning, discoloration, smell or anything, so do not go by what it looks like.

holmesnmanny

Take off the battery connections and look at them for corrosion build up. It may look fine but there could be a coat of corrosion around the battery if the battery is starting to go bad by way of leaking. What you can do is wiggle the connection or hit it with a hammer on the side so that it rotates along the terminal when it doesn't start to see if it's not getting a good connection. I had an intermittent starting problem before as well and I bought a battery connection cleaner tool until I could get around to buying a new battery. Just a thought.

gotglasses

I've had a recurring cold start problem in my 97 accord for years and spent thousands of dollars. When the temperature falls below 30 degrees F it coughs once, spark is cut off and it floods and will not start. It gets towed to the dealer who puts it in the warm shop , where it of course starts! THe sun on a warm winter day has same effect and is cheaper.

I've been using an emergency auxiliary ignition system to put spark into the distributor and the car starts immediately. Once it has run for a minute or two and some heat is felt on the engine it can be started normally. I believe there is a temperature switch that has never been located.

Any ideas?

phootbag

Leave the car overnight at the shop, OUTSIDE, and have someone diagnose it in the morning when it won't start. Of course, when the car is fixed, buy the tech a beer because working in sub 30 temps is not fun.

Lost Again

While I agree with a master tech from a Honda delaership......

Can you at least tell us what has been tested/replaced.....and that this is the same gen Honda?