After 5 months of apparently running well, I think I'm getting a reoccurence of this issue I posted about back in November.

Start the engine, it fluxuates between like 0 and 500-1000 rpm, basically almost dying every 2 seconds or so. Sometimes it can't save itself and dies. If I give it gas, it usually dies when I let off. I also doesn't run smooth on throttle. almost sounds like something skipping, and very wet sounding.

Putting off a little smoke at times, no clouds, but smells like its running very rich, can smell the fuel alot.

Did the map whack. worked last night once the engine got warm. Ran fine this morning. Didn't this afternoon. Whacked it again, got it running smoothly after several minutes/tries. Mile down the road, engine tone changed and lost all power. Stopped whacked again, was ok, got me to destination. No so lucky on way home, once running, no power, stumbling at any throttle change, died at no throttle. Got it the 2 miles home on a rewhack, crossed fingers and green lights.

removed map sensor at home, checked for debris. replaced, still no good.

removed comptech intake, front of throttle body looks ok, no real buildup that I can tell. ran engine, no improvement. sounded like compressed air blowing/sucking from somewhere on throttle.

checked the PCV valve. it rattled (thats good, right?)

tried putting in my old map sensor. no improvement.

reset ecu. no improvement.

no CEL yet.

car is currently at 777XX miles, oil change ~250 miles ago (2 sundays ago, mobil 1). Added a bottle of Lucas fuel system cleaner at last full tank (thursday, ~130 miles, 3/4 tank ago). Shell gas. Figure its not the gas, maybe the cleaner did something, though why it took 3/4 of a tank to show up.

Going to pull the plugs once the engine cools off. If they are pitch black like the ones I replaced last time (all 4, entire tip past threads dry burnt black looking, black burnt looking ring at bottom of ceramic part) , I'll replace them. I think that was a culprit last time, since once replaced the engine blew a bunch of carbon/crap out the tailpipe then ran like a champ.

Does any of this sound familiar? Am I on the right path?

Is it possible i overwhacked the map? wouldn't that cause a cel?

think I should give the valve clearances a once over?

 

I think it might be time for a new MAP sensor and the zip tie securing thing that Honda put out for it.

 

Try cleaning the throttle body with carb cleaner.

 

A clogged TB or IACV would affect idle but not induce a rich running condition.

Sounds like a few things are factoring in. Raw fuel smell suggests way rich as you mentioned. If the car has been running rich all along due to whatever reason, you can get fouled plugs which further add to the problem(s). Carbon could build up on the O2 sensor(s) though that could've given you CEL. However, from my experience a clogged O2 sensor with too much carbon buildup could work partially. The output will show the constantly alternating lean/rich condition deliberately run by the factory ECU but the reading would be slow and inaccurate (which the ECU might not recognize it or throw a CEL).

First thing I would do is to check the plugs. If they're pitch dark and you think that they have been like that for long, chances are your O2 sensor(s) could've been permanently damaged. In that case, unbolt the 1st O2 sensor (more upstream) and see if it's like spray-painted black. In that case, it's toasted.

Once you know the plugs and O2 sensors are working in good condition, then find out what's making the car run rich if it's still doing so. Since a new MAP didn't work for you, I would tend to rule out MAP sensor for now.

These are what I would do to diagnose the problem.

EDIT: Don't rule out MAP sensor just yet according to Xviper.

 

thanks, I'll check those out.

 

A couple of things unclear to me.

1) Why no CEL even losing power that bad?

2) Your older thread mentioned about new retainers and 32 collets. I assumed you mean valve spring retainers and valve keepers? In that case, why? And how did you replace them?

 

It's uncanny that the MAP Whack gives you some relief although it seems to be shorter and shorter lived. The fact that it still does alleviate the problem even briefly might indicate that this should not be abandoned just yet. See what Ultimate Lurker wrote about this topic some years ago:

https://www.s2ki.com/forums/index.php?showt...ensor++problems

A stumbling idle or power loss may not necessarily be seen by the ECU as a "problem" that can be attributed to a bad sensor. It may be getting a "good" sensor signal and just trying to rationalize it by running the motor as best it can. I think UL tried to explain this in the link I put up.

 

In that case, I take back my statement about ruling out MAP sensor just yet. I wonder how often does the MAP sensor act up? Is it related to mileage? I'm at ~52k so maybe mine will come up sooner or later.

 

According the UL in that link I put up, brand new MAP sensors can be "off". I don't think there is any rhyme or reason to it. Mine is original on a 5.5 year old, 65,000 KMs car and it's never acted up. I did zip tie it a couple of years ago.

 

yes, i bought new valve spring retainers and keepers. have not replaced them yet though, the originals still appeared good. more of a piece of mind fix.

UL's thread sounds alot like what i am experienceing.