I have a 91 Accord that my son has done a ton of work on. He is a mechanic (in training&#128527. He put on all new exhaust and headers, removing the catalytic converter and replacing with a test pipe plus a 4 inch exhaust. It is now really bogging. What I mean is that I have my foot on the gas and it's like it's losing fire or something because it won't go. If I keep trying to accelerate, it will backfire. If I take my foot off the gas pedal, then I can push the pedal again and it will start to go. It is idling really low too. We have replaced the distributor, along with the cap and rotor. We have new plugs and wires. It has a new timing belt and water pump. The headers were from an Acura and supposedly are interchangeable. We have timed it with a timing light, but I thing the ignition timing might be advanced too much. We replaced the distributor because another mechanic thought that was the issue. Also, I can't see anywhere that we can adjust the idle. The car is an automatic with a kickdown and the throttle body doesn't have a screw to adjust anything. When I start the car cold, it idles to about 2200 rpms and then idles down to almost nothing, practically dies, then idles up to about 800. Any thoughts on why I keep having this issue? My next purchase may be a new throttle body, but I'm still not convinced that has anything to do with it. Any help is appreciated.

 

There are a number of things that can cause this....Valves out of adjustment, EGR being stuck open can do it.... or could be clogged throttle body ports, or the idle air control (IAC) &/or the fast idle thermal (FITV) valves.

There are a few DIY threads in the FAQ on how to remedy these issues.
Valve Adjustment; HOW TO: Adjust the valves on your F22 - Honda-Tech
IAC & FIT cleaning; https://honda-tech.com/honda-accord-...tv-tb-1844067/

The links for the EGR port cleaning are broken..... I'm sure there is a video or another thread online for cleaning the F22A EGR ports.

Does the check engine light work and is it on or flashing? Have you tried to retrieve any stored codes from the ECU?

 

Check engine light works, but no codes when we check it. I was going to buy a new throttle body. Our old mechanic jimmy rigged it because it wouldn't adjust and was loose (?). I will have my son check all those things.

Is there anything about the new exhaust that could cause this? It doesn't seem to have any leaks. Bolts on the headers are all tight and we put in brand new carbon fiber gaskets.

 

The throttle cable was adjusted somehow. Not the throttle body. I'm sure you knew what I meant.

 

Looking at your exhaust setup. I'm not sure what effect a 4" exhaust would have on one of these engines. What other modifications have been done to the engine, is it still stock internally?

I don't want to get into one of those, "exhaust requires back pressure" conversations, because it doesn't. However, what it does require, is a consistent temperature and constant laminar flow. In a larger 4" exhaust you will loose temperature and laminar flow very quickly. The gases kind of stumble around inside the tube at lower RPM causing turbulence when you try to floor it. May or may not be your issue, just throwing that out there. As that is the only thing your son changed.

Check for leaks...... before the O2 sensor!

 

Your timing belt is probably off by a tooth or 2 most likely to the cam is retarded side.

 

I'm having a similar issue... 92 accord, lots of work done to it including exhaust and air intake.... plugs wires etc... starts and runs fine example cold, but when it warms up a bit the idle goes too low and it doesn't accelerate and backfires... any inside guys?

 

Hi Kara,

I finally figured out that it was my O2 sensor. If you know a mechanic it's a really easy fix. Problem solved.

 

My O2 sensor was done already... just figured out it was bad gas from sitting ... now to clean fuel filters and she should be good lol

 

Yeah. That'll do it!