I bought a 92 Honda Accord and I'm trying to get it running. I'm having problems. It will turn over, and sometimes start, then go for a random amount of time before shutting off. It does not struggle before it turns off, just cuts like as if I were to turn it off myself. After it stalls out, it won't start for a while then half an hour later or so I can get it to start with a similar result.

I have also had a second symptom, after I had started it and gave it a few revs, the revs just started fluctuating between 2000-3000 RPM without any input from me

I'm really not very clued in with cars; but trying to expand my knowledge as it is sort of part of my trade as a first year Mechanical Fitter.

Bringing my tools home tomorrow to have a look at some things; what should I check for?

Thanks!

 

I've went ahead and pulled out the ignition switch and main relay. I will buy a multimeter tomorrow to test continuity to see if either of them are the culprit!

 

Main relay more than likely

 

I am yet to test the relay electrically, but I did feel it while turning the key over and it was ticking like it should. I will test it this afternoon with a multimeter to investigate further. Cheers for the input.

 

If she starts and runs even a little, the main relay in not likely the problem. If you haven't done so, try wiggling the key while it's running, to see if the engine stops..if it shuts off, a bad ignition switch is indicated..

Could be a fuel pressure problem too, but if I were you, I'd focus on spark as the cause.

For fluctuating RPMs read up on Idle Air Control Valve (IACV)on this site. When things are right, these cars should idle about 700-750 RPM's.

Assuming the car has the correct ECU in it, consider reading up on how to check the trouble codes that might be stored. Especially if the check engine light is on.

The #1 thing that has caused that shutting off behavior in mine has been the Ignition Control Module (ICM) (Ignitor) failing. It causes inconsistent spark, causing combustion to interrupt suddenly. The sudden dying, and not being able to get it started again until a little time has passed, also points to the ICM. Unfortunately, the ICM doesn't report its status to the computer. It is a small part, about the size of a book of matches, inside the distributor, with several wires going to it. It's the heart of the ignition system and produces the hot spark needed to ignite and burn the fuel in the combustion chambers in the cylinders.

 

Thank you for the input, I appreciate it. I did try wiggling the key in the ignition and it was no more prone to stalling then usual. I also checked the ignition switch assembly for continuity as seen in this video : and it all seemed to come back fine.

I then checked the Main Relay/Fuel relay as seen in this video : and it seemed fine.

I will remove the distributor over the weekend and see if there is any obvious issues. As for testing it - Is there anyway that you reccomend?
"
1. Remove the distributor cap, the distributor rotor, and the inner cover.
2. Disconnect the BLK/YEL, WHT/BLU, YEL/GRN, and BLU wires from the ignition control module (ICU)
3. Turn the ignition switch ON. Check for the voltage between the BLK/YEL wire and body ground. There should be battery voltage. If there is no battery voltage, check for an open in the BLK/YEL wire between the ignition coil and the ICM. If there is a battery voltage, go to step 4.
4. CHeck for the voltage between the WHT/BLU wire and the body ground. There should be battery voltage. If there is no battery voltage, check for faulty ignition coil or an open in the WHT/BLU wire between the ignition coil and the ICM.
5. Check the YEL/GRN wire between the engine control module (ECM) and the ICM.
6. Check the BLU wire between the tachometer and the ICM.
7. If all tests are normal, replace ICM." - From Service Manual, posted on here by user Billyrusa


I will endeavor to learn how to check codes this week, and will read up on the IACV. Cheers mate!

 

There is a test for the Ignitor in some of the old books, Haynes, etc. You have to get to it and get the wires off of it and then use your multimeter to check the ohm/resistance between certain terminals to determine the health of the ignitor. In my case, I got cut cut off, left the key on, pulled a plug wire, coil, and arced the spark to a big screwdriver. I could literally see the orangish spark, which is what a weak spark looks like. The spark required to keep ignition going is white hot, not blue or orangish. I don't recommend that kind of test because even that weak voltage can do serious harm if you become the path to a ground.

If you know anything about the car's history, and find that the Ignitor has a whole bunch of miles on it, it is likely what it bad and causing the stalling.

But the idle fluctuation could be a number of other things. When you look at the IACV and disconnect the plug on it, if the idle settles down to a low, stumbling idle abut 550rpm, but does not stall, then your IACV is dirty or bad. But if pulling the plug on the IACV causes the idle speed to soar with no fluctuation, then you have air getting into the intake (vacuum leak) from somewhere else, and when the IACV is connected, it has been doing battle with the excess air, causing the rising and falling idle speed.

If it is a vacuum leak, search here for ways to track it down. Little mist of carb cleaner sprayed near it will get instantly sucked in and the the idle will briefly soar. Perhaps somebody worked on the car and took something apart and didn't seal it up properly afterwards. The whole intake of the engine is the place to search for leaks. For example, there is an EGR valve on the left end of the intake. Be sure to check the it is seated properly and is sealing. If you find that is is sucking in air at idle, then the valve is bad or clogged up. Whi

As for the main relay, when it is bad or messing up due to heat, it is always a starting problem (no signal to the fuel pump to start delivering fuel) but it sounds like yours buzzes when current hits it, and doing its job.