Long story short I had upgraded my cam shafts from Skunk2 tuner 1 to Skunk2 tuner 2 cams. Everything went fine the motor ran perfect for a few weeks then suddenly i heard a knocking sound from the head, i checked the valve lash and most all the ex valves were tight somehow. I had set the valve lash correct when i installed the cams. So i set the valve lash correct again and the motor runs perfect now with no sounds ect. Motor is tuned on s100.

But after this issue the next day i started the car and it would struggle to idle unless i give it gas for a few seconds. then it idles perfect. And if the motor is warmed to operating temps the motor will start up just fine and idle so it only does this on a cold start! what could be the issue here?

I'm thinking the IACV needs to be cleaned out??

The other issue I'm having now is that the motor goes completely lean at 4k rpm i can't rev past it and it just goes super lean as i can see on my AFR gauge. Below 4k rpm the AFR is good. What could be the possible causes besides low oil and the dizzy.

 

If it was cold-starting just fine up until recently, you probably have a faulty ECT sensor. I would say, look through the cold-start calibrations within your S100, but if you weren't having issues prior, more than likely its just a bad sensor. There is a test procedure for the sensor based on temperature ranges, but its typically easier to just swap in another sensor and see if it resolves you issue.

 

Thanks!, well i just figured out my ECT switch was bad when i noticed my fans would not turn on recently so i jumped the plug and the fans turn on, so now i guess the ECT "sensor" is bad so this might explain the cold start issues as well as the rich fuel smell i smell when i come to a stop. I just didn't know it had relation to a cold start and rich idle. It stumped me cause it really started after i redid the valve lash.

 

Yeah no problem. And yes, ECT & IAT are crucial to the Honda ECU to determine how much fuel to inject into the engine.

 

Sweet thanks again! looks like I'm in it at just $40 !

 

So i replaced those two sensors and my fan comes on now but i still have the cold start issue! what can it be?

 

Try "rebooting" the ECU/ECM.

Also clear any codes. 94

 

I thought of that but didn't unplug the edu its tuned on a hondata s100 ill try tonight when I'm off work only thing i can think of is calibrations on the cold start setting on the s100 got reset but this happened as soon as i did the valve lash! what could be the relation?

 

Coincident, maybe. 94

 

Could be that massive IM you have for such mild cams. ?

 

Im using Tuner 2 cams there plenty sufficient for the motors setup. The motor was running fine and strong and was not doing this before i did the valve lash so I'm wondering what the cause can be from. The cams and manifold would have nothing to do with this.

 

Tried resetting the ecu but it didn't help.

 

Still have this issue can't figure it out guys!

 

Car is now in limp mode i think cause it goes completely lean right when it revs to 4k rpm. the afr will be fine before 4k rpm but soon as it hits 4k it goes lean and won't rev past that.

 

I reset the ecu again and its fixed now but im still getting a cold start.issue

 

Did you retune after putting these cams in?

They will run differently than the other cams on the same tune...

 

Haven't retuned it with the new cams but it still runs good besides a bit rich at idle i will get the supercharger back on soon, id rather tune it once rather than two times. I will have it back on and tuned in a few weeks. If the drivability was not good id get it tuned but the AFR is good so I'm not worried about retuning it. Although id like to see what my gains are from switching from the skunk2 Pro series manifold and 70mm throttle and skunk2 Tuner 1 cams to the skunk2 Ultra street manifold with 74mm throttle and skunk 2 tuner 2 cams.

 

to update this thread for tech sake i now have a new issue, the engine will not turn over so i will have to figure it out with further testing of the distributor, im guessing my coil went out. I have a new OEM ECT sensor and switch to instal once i get the engine to start. Ill report back sometime soon.