99 Accord LX sedan, 2.3 L V-tec with a 5 speed 232,000 miles.
This is related to the car I just bought last night (harmonic balancer thread), but I didn't want to add this to it, as this would be off that topic. I even did a search (using the search box, along with looking thru the engine forum and couldn't find an answer or thread that's similar to the issue I've come across.
When first started (engine idle speed of about 1200 or so) the engine will rev cleanly up to red line. But, after it gets some temperature in it (idle speed drops to 750 or so), you can floor it, and hold the pedal to the floor and the engine will literally bog down and fall flat on it's face (might rev to maybe 1000 rpms). This is without any load and the hood still open.
I did try working the throttle body lever, and after a minute or 2 of holding it wide open, it would start to rise in RPM, and you can hold it at 3K or so, and it'll run fine like that (even brought the cooling fans on). If you release the throttle lever, it'll drop engine speed and idle normal. Then it might pick engine speed back again (like normal), or it might just sit there and taunt you. WTF?? Put it in 1st gear, or reverse, and slipping the clutch, it'll stall right out.
I've had my Actron scanner on it, and the CEL/MIL light is off, and no codes are present. If you move the selection on the scan tool to data, it gives you a full reading of all the sensors, and everything is reading within spec (even when acting up).
Any ideas what might be going on/causing this problem? This one has me a little perplexed. Thanks for any help you can offer.

 

What are the short and long term fuel trims reading?

 

I don't know right off hand, but I can get you a reading sunday in the daylight (I knew I should have wrote some of that stuff down).

 

Just for the heck of it, what are the colors of the three wires plugged into the MAP sensor.....yes going off the deep end but you did just get the car and not really sure of the work done to it before you got it.

 

That's an easy one, gray connector with red, green, and yellow wires.

 

I screwed up, in that I pulled the battery friday evening, to get a charge back in it. But the numbers I have at the moment are ST FTRM1 0.0 , LT FTRM1 -2.3 (with an arrow pointing up). ST FTRM 11 and 12 are 0.0 each. Fuel sys 1 open1 and fuel sys 2 N/A ign adv -10.5.
When I tried to get it to run today, it wouldn't stay running at all, and it barely ran when it did (less than 500 rpms on the tach, 362 rpms according to the scan tool). I'm begining to think fuel pressure, as I can hear the pump run, but I think FP is low. I need to get a guage on it to know for sure. At least this body style (C6) has access to the fuel pump thru the trunk floor or somewhere like that (had to drop the tank on my 97).

 

Are the wire colors to the map sensor, yel/red, grn/wht, and red/grn? The second color is the stripe.

Short and long term fuel trim 1 are both normal. Don't think the stftrm 11 and 12 apply to your car?

Since there was a harmonic balancer issue, I'd verify the timing belt did not skip. Get the crank to top dead center, then check that the cam is at top dead center.

Just read your harmonic balancer thread. Did you replace the harmonic balancer already? I don't think the harmonic balancer has teeth to spline with the crankshaft at least on older accords.

I'd avoid running the engine, because that key does hold in the crank timing belt sprocket along with the harmonic balancer.

 

Yeah, those are the colors, and they're actually plugged into the TPS (thought that was what I was supposed to be looking for), since it and the MAP sensor can get them easily swapped (saw a thread that someone did that on). I'll take a look again on monday for the colors of the wires, as I had a bunch of other stuff I was trying to get done today around here while the weather wasn't too hot.

No, I haven't replaced the balancer yet, but I did get 1 ordered up. I planned on pulling the covers (got a valve cover gasket on order too), and having a look at the timing belt, and it's marks, along with adding a balance shaft seal retainer kit. I did that to both my 97 and my wife's 2000 Accord after her's spit the seal out and dumped 1/2 it's oil suppy in 30 feet of our driveway. I'm also going to do a cap and rotor, along with plugs, as it's probably due for them too. I know people seem to think these cars will go forever without doing anything to them, but as they age and get miles on them they do need some things fixed or replaced. I'm not planning on running the engine anymore, until I get the new balancer on, and check the timing (belt end). It'll probably be a few days before stuff comes in though, so not much will be happening right away. Maybe I can get a little more caught up, so I'll be able to give it some quality time. I did debate with myself on ordering up a belt kit though, but I'd really like to get a look at what's already there first, and see if I can get it to run better than it currently does before I go in there to do the belts, and maybe the water pump too.

 

Sounds like the TPS and map plugs are switched on your car. Good catch Poorman, I keep forgetting to ask about that.

 

Actually they are correct. I had to dig out my Haynes book to verify which is which (MAP is on top of the TB), and has from left yel/red, grn/wht, red/grn. This means that's not it.

I'm not going to run the engine until I get the balancer installed. And I do plan on taking a look at the timing marks (along with adding the balancer retainer clip while the cover is off).