Car stalled at a stop light and now won't start. Seems like the fuel pump is working a getting gas to the injectors. Spark is good on all plugs. Tried a new main relay - nothing. Any ideas? ECU doesn't throw any codes.

Does the CEL go on for 2 seconds and then go out, when the ignition switch is turned to ON (Position II)?

Yep - CEL on for 2 sec and then out.

The problem resides with the distributor. Even though you have spark, it may be firing at the wrong time. Therefore, I would replace the Ignition Control Module (ICM) and coil:

https://www.askmehelpdesk.com/cars-t...tml#post265896

If the problem persists, replace the distributor housing (Honda genuine only) and install the new ICM. If this fixes the problem, it indicates one or more internal distributor sensors are bad. This is very common on Honda distributors, which usually only last 50,000 to 100,000 miles.

Thanks, I'll look into that. Any way to test the Ignition Control Module and coil?

Bench testing these components is a waste of time. The tests are very unreliable. Instead, I recommend replacing these problematic components every 120,000 miles or 10 years, whichever comes first. Shop for price and warranty.

If the Ignition Control Module (ICM) and coil went bad, would it cause the car to suddenly stall?

Absolutely. ICMs are legendary in doing this. If you want to go budget, first try replacing only the ICM. However, this also happens from coils breaking down under load (heat). Heat is the enemy of both of these components.

Since your CEL comes on and goes off normally, I know the problem is not with the ECM, main relay, fuses, or ignition switch. Instead, it is with the distributor--I'm certain.

Thanks again, I'll try this tomorrow and post the results.

Great.

Any chance that the timing belt slipped/jumped and caused the stall and no start?

Here's how to replace the ICM:

https://www.askmehelpdesk.com/cars-t...tml#post265896

Be sure to apply the heat transfer compound to the back of the ICM.

Sure, that's possible; however, not common. Sudden failures on the road are almost, invariably, electrical-related. For Hondas, this normally means ICM or coil failure.

ICMs have a microchip inside that needs to open and close the primary circuit of the coil at the exact time the ECM says. If the chip starts to fail, the timing is lost and the engine stalls. You may still have spark, but it's just not at the right time.

Is there a chance that the timing belt could have slipped/jumped for some reason causing it to stall and not start?

Again, there's a chance that could have happened. If it did, there's a chance your engine has been seriously damaged, since it's an interference engine. I just don't think that's a high probability event.

Remove the oil filler cap and see if the camshaft turns, while someone else cranks the engine. If it turns, the timing belt is likely fine and I would not focus on it as a likely source of the engine not starting.

It's not uncommon, at AMHD, to have 2 or 3 Honda distributor problems a day--they are just that common.

I kind of doubt it too, seems like I would have heard something or engine got rough then stalled. This didn't happened, just died - like something went bad(like the ICM).

If you had a TB problem, the valves and pistons are toast. I know Honda electrical systems very, very well. I'm positive your problem is with the distributor.

Camshaft does turn.

That's what I figured. Usually replacing the ICM ($64.99, AutoZone) and coil solves the problem. In your 1991 Civic, you should be able to have the car back on the road again in 45 minutes or less, assuming the distributor housing is fine. My gut is the problem is with the ICM.

Put the ICM on and - started right up! I also replaced the rotor,cap,plugs and wires just to have everything fresh. I'm supicious with the rotor, the plastic was melted around the screw that secures it to the shaft and kind of seems like it was slipped down. I had to chip away the plastic to get to the screw. Maybe the rotor wasn't hitting the points at the right time... just a thaught. Thanks for your help.

Good job. You should be in good shape for quite a while. Did you coat the back of the new ICM with heat transfer compound?

Start using your favorite SAE 5W-30 full-synthetic engine oil, changing oil and filter every 6,000 miles or 6 months, whichever comes first.

Yes I put the compound on. The two screws that hold it on were a pain to get back on - almost took off the radiator hose to gain more room. Thanks again.

Hey, it's me again... having more problems. I think this time it's the crankshaft position sensor but wanted to check with you to make sure. So, I was driving along and all of sudden the check engine light came on and the car started to run rough. Also the tach was jumping up and down. I drove it to my parents house (about 3 miles) parked it and turned it back on - cel was off and ran smooth. The next day I tested it out... drove about 10 miles and cel came on and running rough again. The ecu did throw the code 4 which I read that that means the cks. Is this right and if so, where is it located on the engine and who would carry a replacement? I checked autozone and they don't carry it. So you don't have to look back - I have a '91 Honda Civic SI 1.6. One more thing, I noticed a sqeaking noise coming from inside the distributer cap - any idea what that can be. Thanks for your help.

You need to replace the distributor housing (genuine Honda only). The bearings have worn out and, in the process, destroyed the Crankshaft Position Sensor. None of this is serviceable.

Install your new ICM, coil, rotor, and distributor cap on a new housing and you will be fine. Here's how to replace the distributor:

https://www.askmehelpdesk.com/cars-t...tml#post288473

Remember, over 50% of new aftermarket distributors have not worked at AMHD. That's why you only want to go with a genuine Honda distributor housing.

Thanks so much, I'll do that. By the way, where is the crankshaft position sensor located... just for reference.

It's one of the black sensors inside the distributor. The squeaking noise is likely the bad bearing.

OK, is that going to be part of the new distributor?

Yes. The CKP, TDC, and CYP sensors, inside the distributor housing, are crucial. Aftermarket manufacturers, for some reason, can't get them right. Honda distributor housings tend to last 50,000 to 100,000 miles. Bearing and/or sensor failure are responsible for their demise. The bearings fail, once the oil in the grease goes.

I'm baaack. Ok, I got my new distributer today and installed it. Started it up and ran perfectly... for about 20 minutes. I let it idle for a few minutes, drove it up and down the road a few times, then went out to the main road, went about a mile and then suddenly stalled and won't start back up. No engine light came on. I was going about 40mph when it stalled. I was able to coast into a parking lot. I waited about 1/2 hr and tried to start it again and nothing... just cranks. I notice when cranking the battery light flickers. Any ideas this time?

Did you install a genuine Honda distributor housing?

When you turn the ignition switch to ON (Position II), does the Check Engine Light (CEL) come on and then go off after 2 seconds? If not, the problem is with the ACG (ALT) (S) fuse, in the under dash fuse/relay box; ECM (perform the K-Test, below); main relay; or the ignition switch. Perform tests in that order.

The K-Test: Remove the MAP Sensor connector and turn the ignition switch to ON (Position II). Using a multimeter, check for 5 volts going between the MAP Sensor connector's reference wire (+) and ground. As you look at the connector, this is the socket on the right. Really press the black test lead into a cleaned main ECM ground on the thermostat housing. If the voltage is low, it's probably indicating ECM failure. Most failed ECMs will record a fraction of a volt. To me, the K-Test is simple, elegant, and accurate.

I knew that you were going to ask me that. No, I didn'n get the genuine - cheapest I could find was $550 for whole or $280 for housing. I wanted to get all new inside and $550 is pobably more than the car is worth and I couldn't afford it. I got a whole new distributor for $150 made by AIP Electronics. I hope that's not the problem. I do know that the CEL comes on but not sure if it's 2 sec or longer. I believe it's 2 sec. I do hear the feul pump goning on when it's in position II.

Unfortunately, I believe the new distributor failed. I have seen this many times. You might be best served by going to your local salvage yard and picking up a used one for around $55.

Even if it was running for about 20 min. you think it failed? What would fail in it? Any way of testing?

The problem is that one or more of the internal sensors (CKP, TDC, and CYP) fails. I don't know why it's so hard for aftermarket part manufacturers to get it right. The problem is never with the ICMs or coils. I've seen this happen hundreds of times. I don't know how to test the internal sensors. The problem may also be how they are adjusted (positioned).

If your CEL comes on and goes off normally, when you turn the ignition switch to ON (Position II), and you can hear the fuel pump run, then the problem is with your distributor.

Yeah, I can't see how these places can sell the parts if they don't work. I'll try to find one at the juck yard and try that. I think that is going to be my best way to find out if it's the distributor. Thanks for your help again, I'll let you know what happens. Just an afterthought... Is there any wires or connections that I can check - maybe something is loose or corroded?

. Check the connections at the tower.

. Turn the ignition switch ON. Check for voltage between the BLK/YEL wire and body ground. There should be battery voltage. If there is no voltage, check the BLK/YEL wire between the ignition switch and the ICM.

Confirm to me that the CEL comes on and goes off normally.

Sorry, what's the tower?

Does the CEL come on and go off normally?

I believe it does, I can't check it right now - the car is still at the parking lot where I coasted in last night. I'll be going there soon to check it out.

Towers are where two or more major connectors are stacked together. Honda frequently uses this setup on distributor connections.