The CYP sensor senses the position of cylinder #1 for fuel injector timing.

Tach signal comes from the ignitor.

There is some redundancy in the CYP, CKP, and TDC sensors which is why the engine continues to run w/ a fault in CYP.

good luck

 

Those 3 sensors together tell the ECU what position the cylinders & camshaft are in. There's some redundancy like Texas said.

The ECU uses that to synchronize the spark and also the fuel injection. And beginning in 1998 the tach signal comes from the ECU.

 

The car is still running with the persistent P1382. But the engine lacks power, runs a tiny bit rough, and is not getting good mileage. I'm going to replace the ECU...

I'm looking at car-part.com and other sources for a replacement ECU. The part number of my original ECU is 37820-PAA-L11. My car is MT, but I'm finding this same part number called out for both AT and MT cars in listings. Of course, there are more many more AT parts on the market - so the prices are better for AT listings - but useless to me if they wont work in my MT car. Are the ECUs really the same for AT and MT on 1998 Accords?

I understand I'll have to deal with the immobilizer - the normal route being to get the new ECU flashed so that it will trust my key. Personally I don't think any thief is going to waste their time with my 1998 car... so at this point the immobilizer is an unwelcome hassle. Is there any way around it? Can independent repair shops do the flash? Or do I have to go to the dealer?

Thanks!

 

The ECU part number for an AT on the honda parts site is:
37820-PAA-L61
37820-PAA-407 (updated version)

For the MT:
37820-PAA-408

It looks like you have an AT ECU in your car and not a MT. Get the MT PCM. I am not sure why you have an AT ECU in there.

 

Ebay is also a good source for used ECU's.

good luck

 

correct, i bought mine on ebay for 25$

 

Yes, ebay or car-part.com seem like good sources for the ECU.

I checked with my preferred local independent Honda mechanic - and he says he cant do the ECU/key immobilizer reprogramming. I Really don't want to do business with my local Honda dealer. Is there anyone that offers ECU/key programming as a service? I'd send them my new ECU and existing keys... they hook it up, program my keys into it, and send it back...

 

call a locksmith to see if they can program the key.

 

She's running again! I put in a junkyard ECU and had a locksmith program the immobilizer. Interesting thing here is that the dealer wanted $100 for the job - but the locksmith did it for $35. He had an aftermarket device that connected to the OBD plug under the dash, and the job took 10 minutes to program the two keys into the new ECU. The CYP code is now gone and she chugs no more!

So now I can move on to yet more projects.

I still have a code popping up after about an hour of runtime. I have not had it scanned, but I suspect its going to be the P0420 ("Catalyst System Efficiency Below Threshold") that was part of my initial collection - maybe a bad o2 sensor, or maybe a shot catalytic converter.

I also have a lot of front end suspension noise. I think I need new struts and I see one of the CV boots is shot... I'm still on the original struts and axles. Yet more expensive parts... I'll have to spread that pain out.

 

My 98 V6 accord was surging or chugging as the original thread said. While driving the rpm's would suddenly drop and the car would just coast. All of a sudden the power would return, Bam! all at once, run for a while and repeat the cycle. The only way to drive the car was by pumping the gas pedal on/ off. No codes or check engine light. I spent a lot of time diagnosing this issue. It turned out to be the pcv valve. I pulled the valve and cleaned it with carb cleaner and put it back in.The car ran perfect after that. I replaced the valve with a new one immediately. My conclusion is that the cars computer and sensors were constantly having to make adjustments to the air/fuel ratio to compensate for the failing positive crankcase ventilation valve. And or the defective valve causes a vacuum leak symptom to the engine. Although I am responding to an old post, I feel this response is relevant as it just happened to my Accord. On a separate note, a great resource on you tube; Scotty Kilmer. A career mechanic who is very helpful, look him up!