First of all, thanks for all the welcoming comments. I have a 1994 Accord LX, 2.2 L, FF2B2, and auto tran. I bought this car for just $400. It had a few issues most of which I've fixed. The car is idling good but stumbles/ sputters under hard throttle. I replaced the timing belt, seals, idler pulleys, cap, rotor, plugs, and air filter. Egr valve has been cleaned, diaphram holds vacuum and @ idle the car will stumble if I apply vacuum to it and back to smooth idle when removed. The last thing I tried today is leading me to suspect the MAP sensor and would like to get your thoughts on what I see or anything else I could try to diagnose the problem. I attached a vacuum gauge to the intake at the brake booster line, started the engine and allowed it to come to temperature. Engine vacuum @ idle is is 19-20" Hg. Then raced the engine off idle. I opened the throttle slow and easy and the engine throttles up smooth. Did this over and over again, each time increasing the rate of speed I would open the throttle. Each time vacuum would drop accordingly then increase and stabalize. This was true till I started to hit the throttle fast and hard enough off idle the vac would drop to 5-7'' Hg and here the engine would sputter and hold @ this vacuum or slowly increase vacuum/rpm and smooth out. I can repeat everytime. Can the MAP sensor be sending bad signal to computer at this vacuum? Do anyone have any other suggestions? Thanks

 

No CEL, or at least one that has not been resolved? Does this ONLY happen when the car is warm or will the same thing happen when it is cold, or warming up.

 

Thanks for the reply! Its doing this cold or hot, seems a little worse at temperature

 

We'll this one kind of has me a bit confused.

Again, no stored codes, correct. Are the plugs burning "the same" across all cyl? When you cleaned/inspected the EGR valve, did you happen to clean the ports.

 

There are no codes, I have'nt checked the plugs since I put them in which was recently but I can do so later, and when I cleaned the EGR, I only cleaned the valve itself. The port on the manifold were clear as far I could see, I was afraid to probe in to it and have something fall into into the manifold. Thanks poorman212, I see you try and help alot of members

 

You're welcome, yes I try....hope it does help someone.

There is a write up in the DIY section that will help with the port cleaning, not the valve but the actual ports to the intake. I asked about the plugs because sometimes they will show signs.

Also, when you changed the cap and rotor, did you notice any oil inside of it? What brand of plugs, what was the gap.

Again, this one kind of has me, I'm hoping someone else has a few ideas.

 

Whats up poorman212! Lets see, yesterday I checked the plugs, they all appeared the same and normal, they are Bosch Platinums, gap is @ 1.1 mm, i Checked under the cap and there is a small amount of oil in there, I removed the exhaust just before the cat and still stubbles the same. I back probed the MAP sensor on my brother in laws car and compared to mine 1.0V @ idle(approx 20'' Hg) and 3.0 with key in the on position engine off( 0'' Hg) My readings are the same as his but his car runs great. Ruling out MAP. I still have'nt been able to check fuel pressure and now I want take care of the oil in the cap. Can oil in there short or the damage the electronics in there? The computer may also be the culprit.
Just so you know this car ran great for about 2 wks after I replaced all these parts, then started this only every now and then for maybe 2 days and now does it all the time. thanks

 

Another fun filled day on the internet......

Oil inside the dist can cause werid things that is why I asked, hard to say since I can't see it. There is an internal seal that can be replaced, hope you don't mind pulling the dist apart....does you brother in law mind if you borrow his dist? Assuming it is the same.

Again, nothing to back this up since you say it happens when cold, I have to ask about the egr ports...this stumble, does it start to kick in around 1800 rpm's.

Some may warn you about the Bosch plugs, but if it was doing this before then I think you can rule that out.

I said before, this one has me scratching my head, SO PLEASE let me know what resolves the issue...another thing will be learned.

PA, TX, Jim, Ang- any help?

 

Have you checked the fuel system yet for proper pressure, flow rate, and what not? A simple clogged fuel filter might cause this issue. It would flow enough to keep up with the slow acceleration but when pushed hard wouldn't be able to flow enough fuel.

 

Sorry, but I forgot to mention that I have changed the fuel filter. Any other thoughts or ideas.