Help requested

capsidx

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So I drove my F20b cg6 the other day to see if it actually drove. Idled super low and had a 4k rev limit. Im assuming the idle was low because the ECU is a chipped p28 and I had the IACV disabled. Blocked that off and all was ok. I recently redid my harness and plugged the ECU back into the engine harness. TO my dismay it wont start. Everything was working before so please dont say cap, rotor plugs or the obvious check your wiring. I dont know what im missing and its probably because its obvious. My guess is the ICM wire in the cabin. I applied 12 to this directly. Main relay clicks and fuel pump primes. Just no spark. I guess the 12 volt doesnt need to be applied so I can remove that but it should still start.

So any thoughts? I know the IGP1 and IGP2 pins are good and the IG power pins are good as well. Codes are for ECT but that wouldnt cause no spark.
 

Rusty Accord

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So I drove my F20b cg6 the other day to see if it actually drove. Idled super low and had a 4k rev limit. Im assuming the idle was low because the ECU is a chipped p28 and I had the IACV disabled. Blocked that off and all was ok. I recently redid my harness and plugged the ECU back into the engine harness. TO my dismay it wont start. Everything was working before so please dont say cap, rotor plugs or the obvious check your wiring. I dont know what im missing and its probably because its obvious. My guess is the ICM wire in the cabin. I applied 12 to this directly. Main relay clicks and fuel pump primes. Just no spark. I guess the 12 volt doesnt need to be applied so I can remove that but it should still start.

So any thoughts? I know the IGP1 and IGP2 pins are good and the IG power pins are good as well. Codes are for ECT but that wouldnt cause no spark.

Well, the 4K rev limit would be because the VTEC solenoid isn't operating. As far as the rest, no clue. I'm not really up on my Honda wiring stuff. But, it could be something in the distributor not getting a signal (like the ignition module going bad). I only mention that, as I've had ignition modules go bad on other vehicles before, and they've basically just shut the engine down without doing anything. I had a Malibu wagon just quit while backing into my garage. No spark no nothing. Changed the module and it fired right up.
Just something to think about. Don't know if there's a testing procedure for a Honda ignition module.
 

capsidx

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I was pretty sure the 4k limit was the Vtec solenoid but who knows. My f23 let me rev up to redline without the vtec solenoid it would just be gutless and you would feel the difference. As far as the no spark I can just assume its either the AGS fuse or something with the ICM wiring.
 

Rusty Accord

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I was pretty sure the 4k limit was the Vtec solenoid but who knows. My f23 let me rev up to redline without the vtec solenoid it would just be gutless and you would feel the difference. As far as the no spark I can just assume its either the AGS fuse or something with the ICM wiring.

I only mentioned the VTEC solenoid because I've heard others have that problem when the valve goes bad, or it gets unplugged.
I think you're on target with the ICM wiring though.
If it was a 5th gen Accord, I'd look at power for the injectors. I ran into that problem with my 97 Accord. Thing was, everyone kept telling me it was the main relay, even though I tested it in the car, took it out and bench tested it, put it back in the car and tested it. I knew it was good, and had to look elsewhere. A shot of "satan fluid" and it would run as long as you shot it., told me I wasn't getting any injection fire. Fuel pressure test told me the new Denso pump was doing it's job. It kept leading me back to injectors. Found I wasn't getting 12 volt over to the resistor pack (only had 4 volts there).
 

capsidx

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WEll the F20b doesnt have a resistor box so thats out lol. I still have the original resistor box and injectors for the H23 that I could use but I know its not the injectors. Its definitely something on the ECU end as it isnt getting spark.

PS: I hate resistor boxes because its just one more thing you have to worry about if you dont get the wiring done correctly lol.
 

Rusty Accord

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WEll the F20b doesnt have a resistor box so thats out lol. I still have the original resistor box and injectors for the H23 that I could use but I know its not the injectors. Its definitely something on the ECU end as it isnt getting spark.

PS: I hate resistor boxes because its just one more thing you have to worry about if you dont get the wiring done correctly lol.

Can you check the CKP sensor, or even the other sensor for spark control (can't remember what it's called)? Are they both in the distributor? Or down on the by the crank? Just asking, as I don't know which set up the F20B used. I know my F22b2 uses the crank triggered set up (like the F23), while the F22a1 uses it in the distributor.
 

capsidx

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CKP is in the dizzy on this one. I can check the wiring but the car started before I took the ECU out. I toolk the ecu out and redid all the pins and wires and now that im reinstalling it, it wont start so its definitely something on my end. I checked the CYPM, CKPM and TDCM. Those are all grounds. I need to check the hots for thos pins but they should be good. My battery was hella weak as a bonus. It cranked ok and then died quickly after that so I had to stop testing. I charged the battery and left it in my house so it should be good now. Testing happens on friday but I want to arm myself with as much knowledge as I can so thanks for the recommendation. Im probably missing the obvious.
 

capsidx

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Thats what im trying to do lo, CKP is one thing to check, ICM is another. It primes the pump so IGP grounds have to be good.
 

Rusty Accord

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Thats what im trying to do lo, CKP is one thing to check, ICM is another. It primes the pump so IGP grounds have to be good.

I was going to say double check the grounds as well. I know the G101 on the intake needs to be attached or the engine won't run.
 
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