My new IACV arrived. Part no. 36450-P6T-S01. It comes with the seal as well.
Since I dont connect up the FITV portion of the IACV, I covered them up with silicone caps ;).
Continuing from the previous episode of my engine being flooded. It is confirmed that the 240cc injectors I borrowed were leaking causing the flood.
However, the engine was still hard to start after I swap out the injectors. I being to noticed that almost everything I clean out the spark plugs or swap in new ones, it would start quite easily until the 3rd or 4th attempt (after driving around). Somehow my plugs are getting fouled, but the AFR reading were good at 14.7.
It turns out that the leaks from the 240cc injectors were so bad that my engine oil level increased! I immediately changed out the engine oil which measured almost another extra 500ml of oil.. Thus the fouling of the plugs.
So after changing out the 240cc injectors, changing the engine oil and cleaning the spark plug. I can start the engine easily and reliably only if I open the throttle to 10% (Based on the Hondata S300 read out). My conclusion is that either the IACV (not new) is unable to open fully during cranking or I have to do the IACV learning procedures.
I have tried reducing the cranking fuel in Hondata S300 from -10% to -30%, but it is not as reliable as keeping at 0% change and 10% throttle. Thus I have ruled out having "too much fuel" during cranking. As long as u update the injector size in Hondata S300, it will adjust the cranking fuel accordingly, thus it should be so much of a difference.
Will update once I try out the procedure while waiting for my new IACV to arrive from Japan.
Anyway, it is a win to me since I can start the car reliably now, instead of carrying a spark plug remover and blow torch in my car all the time..
Once I managed to totally solve the issue, I will summaries the whole event and hopefully it will help someone else encounter the same issue.
Before putting in the RDX injectors, I managed to borrow a set of 240cc injectors from a friend and installed them. It did not solve, the hard start issue.
One time, I decided to remove the spark plug in the morning before I start my car, 2 of the cylinder were flooded with fuel! One step closer to the mystery, it is now either the 240cc injectors are also leaking or my ECU was not able to close the injectors fully during shut down.
If this still happens after the RDX 410 swap, I guess it is the ECU that is having issues..
Update on my hard start issue.
My "bypass of the IACV" method did not really help much.
I managed to borrow a IACV from a good friend of mine. I can start the engine now, she is still hesitant to start, some bog and stuff. Sometimes I need to throttle a bit to get her started. Once the engine starts up, it idles fine and I can switch off the engine and start her up easily again.
The last piece of item that I have not change is my ID1050X (Less than a year old, my stock injectors cracked at the nozzle, thus the change of injectors). Now I suspect that it might be leaking fuel into the cylinder causing the hard start.
Just managed to borrow a set of stock injectors, hopefully this will solve the problem. I will most likely get the RDX 410 as replacement.
It has been a long time since updated this blog.
I decided to add this post as I encountered hard start with my engine for the past one month.
The car was driving fine for years and months, without any symptoms of any failure. I drove to work and after I park my car for 8 hours, she decided not to start. Prior to this nothing was added or done to the car.
There was good cranking, fuel and spark. Timing was ok. I changed my distributor to be sure (OEM original rebuilt by myself with new ICM and Coil), still no start. I decided to get it towed to my workshop, obviously it is out of capabilities.
My mechanic/tuner did the same checks but couldn't find any mechanical fault. He decided to reload the tune (Hondata S300) and the engine managed to start. Yeah! Problem solved! BUT nope, the subsequent few days, she was temperamental. Sometimes, she will start right up and sometimes, I did crank until the plugs get wet with fuel... So I had to remove the plugs and let the cylinders dry up of fuel. The next day, after putting the plugs, it will start right up.
So I thot maybe the injectors are leaking and there is too much fuel in the cylinders or I need to reduce the cranking fuel injected, since the AFR was reading richer than normal compared to before immediately after start up (I am running ID1050X, which was starting and idling perfectly). For days, I tried different tunes, playing with the fuel trim in Smanager for cranking, but she remains temperamental.
To be clear, when she starts up, she drives and idle perfectly. No signs of any issue at all; I have my PLX AFR meter, my laptop connected to check for any abnormality.
One day, I notice my AEM Fuel Pressure Regulator is leaking again! (The first I got which lasted for over 15 years leaked and I replaced a new one 6 months ago) I replaced it with a Sard Fuel Regulator. Then she start immediately! Hey I found the fault! NOPE! The next day, the hard start returns again.
Running out of ideas, I decided to clean my IACV. It was quite dirty but that didn't help. Then I notice my IACV wasn't running (usually, there is a slight buzz if I put my ear next to my intake). But even so, I thot the engine so be able to start even with a faulty IACV. I checked my idle screw on my throttle body, it was screw all the way in tight!
What happened was that the IACV was doing all the work of letting air in during cranking all this time! Once the IACV decides not to work, the engine was not getting any air at all, thus the rich AFR reading if she starts or doesn't start at all.
So now, before my IACV replacement arrives from japan. I open my idle screw out and let the engine idle at 1200rpm. At this setting, the car can start even if the IACV is not working. If I turn the idle screw to lower the rpm, I will not be able to start the car if the IACV decides not to work.
Hopefully, this post will be useful to those facing the same problem. I have been searching for answers for the past one month and wasn't able to get any solution or any hint that IACV can cause the engine not to start.
The IACV will open up when the key is turn to "on" (position before cranking) to allow more air to enter into the engine during cranking. It is not just solely to control the idling the engine.
