Hits a wall after 3500rpm

[newaccorddriver]

It appears I have a problem that I cant seem to figure out. I noticed it the other day when I found it hard to accelerate under pretty much all demanding conditions. When I accelerate lightly and shift under 3500rpm, everything is normal like it should be. When I drive it hard, its very noticeable that I lost alot of low end power, and anything past 3500rpm is virtually non-existent, and thats even in 1st gear too. Revving it without load is no issue surprisingly. Cant hear a misfire, or atleast my cars too loud to hear it. Test pipe installed along with full exhaust.




As far as what ive done so far.
Changed plugs maybe 1 month ago
Changed coil just now-no change in performance
Looked at rotor and cap when I did the plugs and they looked fine, for seeing maybe 15000km of use
Rechecked and adjusted timing back to 15 degrees BTDC-was significantly out and is now adjusted to the max. A slightly noticeable change was felt
Checked ECU for codes-none found




I am kinda stumped on whats going on here and why it feels really sluggish. I am also averaging 17MPG which is horrible compared to a few weeks ago(starting to get cold) which was at maybe 25MPG. It was getting maybe 30+ MPG in the summer, so this is definitely a new issue I am facing.

[Oldblueaccord]

I'm thinking it being real cold by you its running real rich when your into the throttle. The 17 mpg seems to show that.


wp

[Dr_Snooz]

If the car is running fine otherwise and the loss of power isn't accompanied by any other symptoms like cutting out, pinging, smoking, etc. then I would think you have an exhaust restriction of some kind.

[w261w261]

Snooz, isn't there something that happens with the motor after 3500 rpm? I know we don't have VTEC, but there's....something. Maybe that's the issue.

[Buzo]

I believe its a timing issue.
Now that you are at 15 degrees, try advancing it a little bit, and test, some more and retest. Even a fraction of a degree is important. Put marks in the adjusting slot so you know where you are and where you were before.

Of course you may want to check if you have spark in all the plugs before moving anything. Hock up the timing light to one cable at the time and see if the light is constantly blinking.

[Bluntman]

Since you have done the tune up items and covered that. I am wondering if it may be a fuel delivery problem under load at higher RPM. May not be at all but the fuel filter was not mentioned. Just throwin' it out there. We have old systems and have seen some ugly filter screens on the fuel pumps on EFI models also. Had to edit, I did not see your MPG had dropped, so now I am kinda stumped without being hands on.

[Bluntman]

Of course you may want to check if you have spark in all the plugs before moving anything. Hock up the timing light to one cable at the time and see if the light is constantly blinking.

Agree. It could be something as simple as a bad plug wire, a cylinder not firing would just spit out unspent fuel resulting in loss of MPG. Check resistance of the plug wires.

[newaccorddriver]

As of monday, my car officially hit the brick wall. Went out to start it and it sounded funny, and then it wouldnt rev past 1500rpm. To top that off, my headers were glowing red hot in the dark. I am pretty positive that all the symptoms were related, and I believe the timing belt jumped a couple teeth somehow. I will be looking into it on the weekend.

[Buzo]

I learned in these days that excess of fuel can also make your car hit the wall.
And I'm talking about only 20% more, so your engine don't need to be flooded with gas to be too rich to won't be able to accelerate.

Remove the plugs and look if they are blackened.

[Dr_Snooz]

My old '76 Accord had a baffle in the exhaust manifold that broke off and fell down over the exhaust outlet. Apparently, it was not uncommon with them. The thing drove just fine around town, but had zero power on the highway. I couldn't even pass big rigs that were going slow. It didn't cut out or miss or anything, just didn't have any power. You can test easily by putting your hand over the exhaust pipe. Assuming you can start it, of course.

I'll be interested to see what this ends up being.

[newaccorddriver]

completely forgot to update this post. What I thought was originally a skipped tooth turned out to be something far more common(atleast to me). The culprit was actually a bad distributor. I checked the belt, started it back up and it died almost immediately. I had a spare one in the trunk and I slapped it in.


Im not sure whats going on, but every few months I replace a distributor. This one refused to turn unless much force was used. I suspect something broke inside and caused a jam. Not sure what it was, but now i always carry a spare around. It will also likely be the first thing I look at when I have issues