I have a 98' civic that died @ idle and will not restart. Hooked up the obd II scanner and got this code with the message - catalyst efficiency below threshold. Is this the converter and will it make the car die and not start? The converter is only about 3.5 yrs old now.

 

A bad cat is not causing the no-start problem.

1) Turn the key to ON(II) and listen for whether the fuel pump primes for 2 seconds (low humming noise in rear).

2) Check for spark (see link in my signature).

 

Fuel pump is building pressure, weather is supposed to be better today so I'll start with the spark. Thanks.

 

Ok, the nightmare begins. I started in on the electrical and the coil had on open so I replaced it. It ran fine so I went ahead and changed cap, rotor, plugs and wires since I was in there anyway. I get about 5 miles down the road and it starts misfiring above idle. So I get back home and take the icm in to get checked and it was faulty on the high side. Put the new one in and drive about 5 miles to check and it starts misfiring again, just not as bad. Is there a wall to bang my head on? Any ideas on what else would cause this? This is the only Honda I've had to work on, so any ideas would be helpful.

Mike

 

Is the CEL ON? Did you reinstall the plug wires in the proper order? Are the spark plugs NGK brand and are they properly gapped? Are the plug wires tightly snapped onto the plugs and distributor cap? Are the wires attached to the distributor coil and ICM tight and not corroded?

 

The cel was reading 0420 still and the multiple misfires and then I cleared it to see if I could get something new. I haven't had a long enough drive cycle time to turn it back on yet I guess, but I'm afraid to with the misfiring. I checked the plugs and wires. All are tight and as far as the order I did them 1 @ a time and I ran highway speeds for 5-6 miles before it started both times.

Guy at the parts store says his hobby is Honda builds and he mentioned the cam positioning sensor built into the distributor and started in on the good resale value with a bad motor.?.

And the plugs are bosch gapped to .044.

 

Also did it have the plastic insulator plate under the rotor? Did you put it back in? If you don't have that, sparks can jump down to the bottom of the distributor and burn out the ICM or sensors.

This might be related to the engine switching to closed loop mode after it warms up. If you don't do anything, just let the car cool off, can you drive another 5 miles before it acts up again?

 

Yes the insulator plate is back in. I'll have to get back on the cool down. I was just getting ready to go triple check everything. And I'll take it for another drive here in a bit. Thanks.

 

Both the coil and ICM originally were bad. When you replaced the coil, the bad ICM may have damaged the new coil. I recommend that you remove the new coil and ICM and have them tested.

On your test drive, if the CEL turns ON, then pull the code as soon as possible.

 

The coil was bad too, I'd have to agree with you. The ICM seemed to be burning coils. I've driven it about 30 miles at various speeds and seems to be doing fine. Thanks for the help.