2002, Accord Cpe, 2.3l 5speed, car has 173k, Motor has 80k, I've put 10k on the car without a single problem since the motor replacement.

Now for the problem!

It started as, a miss at highway speed, an extremely intermittent miss, but a hard miss, one that will kick the cruise control off and will shutter the car. Not undriviable, prior to the miss, the car ran fine averaged 28-31mpg. Some other information, under hard acceleration the car would surge under throttle occasionally.

The car has always started immediately, within the last 2 weeks it has started to on occasion have to crank for 7-10 seconds for car to start, normal is within 3-5 seconds.

So, working midnight shift I've not had a significant amount of time to trouble shoot the problem. So I have done minor things, and before you all roll your eyes I KNOW TROUBLE SHOOT FIRST, RULE OUT PARTS AND COMPONENTS, DON"T JUST SWAP PARTS!

BLAH BLAH BLAH, Ok so started off with, New distributor cap and rotor, Plugs and wires were changed with the engine and they are NGK OEM plugs with New set of wires. Seemed like it helped, the Distributor cap and rotor had 173k on them, likely should have been changed.

Next I had the car crank and NO start, Would turnover no start. I didn't notice the green key indicator on the dash during the no starts. So I can speak to it's indications. I can say I only have one key to this car and has since started several times.

So, with the no start, it acted like it was IGNITION SW FAILURE. I metered out the switch and although meter reading were good the switch seemed to be overly sensitive to very minor movements of the key. So switch was replaced.

I had it licked, car drove fine for a week, moved it while cutting the grass and of course parked it in front of the garage, in front of the pickup that was nesting in it's parking spot in the lower bay. Went to move it and NO START, turns over normally NO START! Pushed it out of the way and got the truck out past it, shoved it into the garage and left it for the night. The next morning I pulled a spark plug, stuffed it back in the boot and went to crank it over to see if it would spark and well, NOW IT'S RUNNING!

Ok now moving in the readers digest version, New cap and rotor, reasonably new wires and plugs, new ignition switch. Never have had a CEL/MIL light at any time, no stored codes.

Today it starts and while in the garage, start pushing and pulling on plugs and connectors. HERE'S what I've found, on the intake Plentum, drivers side, there is a sensor, believe that it is the IAT (Intake Air Temprature) sensor, with the car idling (cold) if I apply pressure to the sensor plug the RPM will dip, if I squeeze the wires it will kill the car instantly. I've done this a dozen times. It doesn't set a CEL/MIL light, just kills it dead.

FINALLY, THE QUESTION!!!

Will the IAT sensor, cause the car to have a NO START? I know I have found A problem, it may not be THE problem, but definitely something that has to be repaired first.

You all know more about these cars than I and collectively together we can figure this out.

Will the IAT cause the Hesitation under load, intermittant hard miss at speed, and occasionally NO START?
Thank you all for your time!!

 

If the PCM saw strange readings from the IAT I could see that causing some drive issues. A total no start, I can't follow that.

Got any pic's of the "switch" and or the wire colors to it? Might help in the investigation.

 

Very end of the intake plentum, black wire with green stripe, and red wire with yellow stripe. Ok although a problem, not THE problem,dropped me again. Luckily was at home just moving the car for mowing. Green security key flashed normally, started stumbled then stalled, would not restart. Acted like no spark, 10 minutes of repeated attempts finally started and restarted every time after. It acts as if there's no spark. So while at the parts yard Chasing my plug, I snagged, Main Power Relay, and a Distributor off a yard car, both were picked up for under the price of one of them new. Is either one a more likely culprit than the other? Thank you!!

 

If it is a no spark issue then it might be the ignitor which is located inside the distributor assembly. You can either swap the ignitor into you existing distributor or simply swamp the whole assemblies. It may not be you issue though. Next time it does not start I would check the tach signal with a test light and see if the light is bright as it should be or dim or non existent which would indicated the likely hood of the ignitor failing. While you were at the yard you should have pulled the IAT and the MAP sensors off the salvage car.

Additionally you can manually jump to the starter and if the car starts right up then you can all but rule out the ignition, ignitor, coil, plugs, wires, fuel etc. etc. Manually jumping it when it won't start to see what it does can help in the diagnostics.