Well I got my car almost 2 years ago, parents got it at a car auction for a pretty good price. When I got it I was excited as all hell when I first saw it, heard a lot of good things about vtec engines. Engine code reference check for a D16Y8 was a hell of a shocker for a person who at the time didn't know the difference between a SOHC and a DOHC. After I started doing a lot more homework I was pretty bummed out that I didn't get the Prelude that I asked for. Oh well she's served me well over these last two years but I've always had a performance issue that has driven me nuts. It's like every once in a while the car likes to show me what it's really got, probably happens every month or so. Just yesterday I got really pissed off following a car that was going 5 under, downshifted into second and punched it to pass, found my self in the red in no time when I had expected to go to 5k and back off, felt like so much more power it really caught me by surprise.

Couple things
The first summer I had the car it had a serious bucking issue, accelerating onto the interstate it would buck at 40MPH, this happened probably 20% of the time. Drove it straight to the mechanic and it disappeared by the time I got there, didn't even turn the car off. This year it hasn't given me any trouble.

Overall since the day I got it the amount of gas that goes to the engine for the amount of pedal I apply is inconsistent. Some times when it is really struggling it sounds like the engine is dying by like 4k, although the frequency (RPM) is low it sounds kinda like the pitch that redline has. The only thing I could say it sounds like is that it's running extremely lean.

Although the bucking issue of last summer is gone sometimes in a steady acceleration there is a lag at around 3k or 3.5k, can't recall which but it is exactly on an increment of .5 every time. Its like it's accelerating about normal then when it hits 3k it shuts off fuel for a rotation then proceeds as normal. This happens on and off.

Some days it feels like it's just not letting me give it more fuel, when accelerating there is no difference between 1/3 throttle and full throttle. This is the most common and irritation problem, changes over as little time as 30 minutes and merging into traffic can get dangerous when I'm forced to run at 5k to get the power that I need to get to 70. This often runs in coordination with the lean sounding problem.

I've spent a lot of time trying to figure out what is causing it and I can't really see any environmental causes, it's just so random. Heat obviously makes everything worse but the degree that it is worse doesn't really match how bad. Yesterday was 95+ and it worked just fine.

New plugs, wires, cap, and timing belt about 10k ago. Did a little looking around for comparable problems and found a few places to start, going to go check the throttle body, order a new fuel filter, and replace the PCV valve. Air cleaner needs to be changed but that isn't the problem. Any body have anything else to try? I'm getting ready to take it to college this fall and would like to get it running good before then. Looking to do somewhat of a full tune up and won't mind spending up to $200 even if it requires throwing a few parts at the problem in attempts to get it working proper.

Thanks,
-B&C

 

Automatic or manual transmission?

Did you install OEM plug wires and cap, as well as NGK spark plugs? Did you also replace the rotor?

Have you adjusted the ignition timing with a timing gun?

Any CEL codes? Does the CEL work?

 

Manual transmission
CEL is working and unlit

The Wires, cap, and plugs were replaced by a trustworthy individual mechanic. Not sure about the rotor. We had sent it to him for this mystery problem, had him do a tune up. Worked pretty good for a while but went back to the normal shortly. I do remember him saying something about water getting built up in some part and he drained that (whatever it was), perhaps you can derive something from my cryptic memory?

Have not played with the timing, any good guides on that? I'm not the most experienced enthusiast mechanic but I follow directions very well, am generally good with my hands, and am very precise.

Throttle body is clean BTW

 

When you turn the key to ON(II), does the CEL illuminate for 2 seconds and then turn off?

Start by removing and inspecting the plugs, wires, cap, and rotor. Post pictures if you are unsure about what to look for.

The second diagram below shows how to check the ignition timing. You need to buy, borrow, or rent (free at some auto parts stores) an inductive timing gun.