My CRX Si pulled a new trick on me this afternoon. I had stopped to pick something up, the car was off about five minutes. When I restarted to leave, it started normally, ran about ten seconds, then the RPM slowly died to zero. When it had stopped there was not the yellow fuel pressure/check engine light. The only lights on were the oil pressure and the handbrake warning. The stoppage was not as abrupt as if the ignition shut off; it just slowly wound down from 750 rpm to zero.

It took about three tries to get it to start again, but once it did it kept running and idled and ran normally the rest of the way to my house.

Any ideas about what may be going on here? My first thoughts are fuel pump. It is at 314,000 plus miles and the original unit. There should be no problems with the filter, it is about 10K miles old. Outside temperature was about 40 degrees.

I suspect this will be a recurring issue; since it has never happened before something must be going south.

 

any codes showing on the ECU? always the first thing to check

 

I haven't had a chance to check those as yet. I will try to do so this weekend.

 

No codes showing. Which is pretty much what I expected. I think this is something outside of the ECU's purview.

Does the ECU read fuel pressure or just the act that the pump should be running based on power to the pump? When the problem occurred I had no check engine light to go along with it, the rpm just decayed to zero.

 

There is not a fuel pressure sensor so the ECU has no idea what the fuel pressure is. Also, the ECU doesn't retain codes so unless you read it when the issue occurs, it will be gone when you turn the key off.

 

Does the fuel pump prime at key-on? When you turn the key, it should prime for a few seconds. Do that a few times and make sure its happening consistently and sounds normal.

I've had something similar happen on 2 occasions, the first was a dirty MAP sensor and old fuel filter. Cleaning the MAP and replacing the fuel filter took care of that.

2nd time my ignition coil was slowly dying due to old plug wires - the measured resistance of the wires was off the charts. It was having hesitation/shutoff issues randomly, until one day it died idling in my driveway. Replaced the coil and and plug wires and it was fine.

Just some things to check before replacing the fuel pump. I'm at a similar mileage on my chassis and have had no issues w/ my fuel pump, but I do wonder when that time is coming.

 

The fuel pump runs when the key is initially turned on, then goes off before cranking as it always has. The pump sounds normal. When the issue occurred it was not accompanied by the Check Engine light so there probably wouldn’t have been a code then either. Ignition system not very old. I had a complete meltdown of that a year or so ago.

On the three restart attempts the display was normal for the start up sequence. Then it finally started and has been doing fine since. But I fully expect it to occur again.

interesting the ECU doesn’t store codes. What use is that?

 

If the ECU is original, its OBD0 which doesn't store codes. The ECU itself will blink to relay the trouble codes.

OBD1 can store codes, though I'm not sure if Honda OBD1 ECUs are setup to do so - I've never seen a code persist. OBD2 stores codes for sure.

One other thing to check is the idle air valve (IACV), your idle may be set low enough that the engine dies when the IACV closes - if the IACV is on the way out or has a loose connection, it could have closed.

What did the throttle pedal do when it slowly died on you? Did the engine respond to throttle input at all?

 

No response from the engine via the throttle pedal at all. Idle is normally 750 rpm and fairly consistent.

 

the ECU does store the codes and they remain there until physically removed by cutting off power to the ECU - the CEL will turn off when the ignition is shut off but the codes remain

 

Between no throttle response and the fact it was hard to start back up when it died, it does sound fuel related.

TPS could also be an issue, but because nothing at all happened when you applied throttle I don't think so. It would be good to look at the TPS connector and test the TPS to rule it out though.

I don't want to say outright that the fuel pump needs to be replaced, but keep an eye on it and listen for it when it primes. You could also jump the fuel pump at the main relay and listen to it in the tank w/out the engine running to see if it is noisy/failing.

Easy things to check right now re: fuel are the main relay, and the injector box.