1998 Honda Civic Repair Question
1998 Honda Civic Misfire cylinder 1 code and now catalytic
This started with car almost stalling in Nov,2007 when I was pulling into parking space. We changed fuel filter. Seemed to run ok until May, 2008. Then code of misfire cylinder 1 started. Next it was misfire on all cylinders, ignition module failure. We have replaced fuel filter again, $10 spark plugs, $60 wire harness from Auto Zone, replaced ignitor from Auto Zone. Oil was changed out with 10W40 last few times, instead of 5W30 per husband thinking higher miles needs this oil. Engine warning light has flashed a few times when I am driving. Engine sputters and will not go over 45 mph at times, then starts running fine. Problem is intermittent until now. Dealership said error code first time they checked was misfire cylinder 1 and I needed to buy their wire harness. Now they said catalytic converter is failing. I am afraid to replace catalytic converter and still have underlying problem that will cause it to fail again. Also we have put several cans of SeaFoam in it and even 2 gallons of racing fuel in to clean out gas.
If the converter is clogged it will have these symtoms, you can have a backpressure test done by removing an 02 sensor and using a pressure gauge to read the exhaust pressure, if it's more than 1-2 PSI the converter is restricting exhaust flow. A vacuum gauge tapped into the intake manifol will do the same, hook it up reading should be 18-22 hg, and it should hold steady, if it starts to fall, exhaust is restricted.
We did replace catalytic convertor and O2 sensor, aftermarket parts. Worked good for 6 weeks, then misfire cylinder 1. We then replaced ignition coil. Still misfiring. Put 44K engine cleaner in gastank. Still misfire. What is next?
Tell me ALL new parts and testing thats been done.
NGK plugs, Honda plug wires, Honda distributor cap and rotor, aftermarket catalytic convertor, O2 sensor by catalytic convertor, aftermarket ignitor, aftermarket ignition coil.
Testing shows cylinder 1 misfire occuring just after start of car, about 650 rpm, misfire happens at highway speeds too. Dealership had told me code for catalytic convertor also.
If it misses bad enough, codes for misfire cylinder 1, 2, 3 and 4 also.
It had a code for ignitor failing earlier. That is why we replaced the ignitor.
We put in SeaFoam several times in gas, and last time used a can of 44K we bought from a car repair guy.
Friday, it was running slightly rough at start and at highway speeds but no engine codes. I started car Sat morning to go home, and it immediately ran rough. Engine warning light flashed. I drove a few miles sometimes only able to go 40 mph, stoppedm turned off car and waited. Restarted the car and light wasn't flashing. Drove home, with occasional rough running at highway speeds. I haven't checked the codes yet this time.
Persistently a code for misfire cylinder 1.
Before we had all the problems, back in Oct, 2007, we had a local garage replace the hoses. He said since he had it apart, he could replace timing belt. I was not sure if it had been done since I had bought it used. So he replaced it. I don't think he replaced water pump.
Also had the belts replaced. We had a sound of belt slipping. Had that sound a few times after he replaced the belts also. Then sound quit. We live in Ohio. This car came from snow belt of Cleveland, so there is a lot of corrosion on motor.
TESTS W/CODES - TESTS -1998 Honda Civic CX
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NOTE: If DTCs P0131, P0132, P0171, P0172, P0335, P0336, P0401, P1359, P1361, P1362, P1381, P1382, P1491 and/or P1498 are displayed, repair these DTCs first. Listed DTCs do not apply to all models.
DTC P0301-P0304 - CYLINDER MISFIRE DETECTED
1.If DTCs P0301, P0302, P0303, and/or P0304 is set, check for:
ï¬ A fuel injector that is clogged or, leaking fuel or air.
ï¬ An open or shorted fuel injector circuit.
ï¬ Spark plug carbon deposits, fouling or other malfunction.
ï¬ Ignition wires open or leaking.
ï¬ A distributor malfunction.
ï¬ Low engine compression.
ï¬ Valve adjustment out of specification.
ï¬ VTEC system malfunction (D16Y5 or D16Y8 engine).
ï¬ A Heated Oxygen Sensor (HO2S) or HO2S circuit malfunction.
Repair as necessary. If no problems are found, go to next step.
2.Start engine and listen for clicking sound at fuel injector in suspect cylinder. If injector clicks, go to next step. If injector does not click, check for open or short in wiring harness between fuel injector and PCM. See WIRING DIAGRAMS article. Repair wiring as necessary. If wiring is okay, replace fuel injector and recheck. If injector does not click, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. 3.Using OBD-II scan tool, check and record freeze frame data. Perform PCM reset procedure. If there is no freeze data of misfiring, perform PCM reset procedure. See Self Diagnostic section. Exchange spark plug from misfiring cylinder with one from another cylinder. Connect SCS service connector. Test drive vehicle several times in the range of freeze frame data or under various conditions to duplicate malfunction if freeze frame data is not available. 4.Using OBD-II scan tool, check for DTCs. If DTC P0301, P0302, P0303, or P0304 is indicated, go to next step. If DTC is not indicated, misfire condition is intermittent due to spark plug fouling. Plugs are firing properly at this time. 5.If misfiring occurs in other cylinder whose spark plug was exchanged, replace spark plugs. If misfiring does not occur in other cylinder whose spark plug was exchanged, exchange fuel injector with one from another cylinder. Start engine and allow it to idle for 2 minutes. 6.Test drive vehicle several times in the range of freeze frame data. If there is no freeze frame data of misfiring, test drive vehicle under various conditions to duplicate malfunction. 7.If DTC P0301, P0302, P0303, or P0304 is indicated, go to next step. If DTCs are not indicated, misfire condition is intermittent due to bad contact in fuel injector connector. Injectors are operating properly at this time. 8.Determine which cylinder(s) misfiring occurs in. If misfire occurs in the cylinder whose injector was exchanged, replace faulty fuel injector. If misfire does not occur in the other cylinder whose fuel injector was exchanged, check cylinder leak down, engine compression and Crankshaft Speed Fluctuation (CKF) sensor. Repair as necessary.