Baldy1998

Hello, I’m working on a 1998 Honda Accord LX 2.3 V-Tec. I bought the car since it needed a motor due to the previous owner over heating it. I swapped the motor out for another same year F23A1 out of another Honda Accord. I put a new timing belt, water pump, new plugs, knock sensor, cap,rotor, and plug wires. The car will run while idling, but once pressure is applied to the gas pedal it’ll die pretty quick.

I cleaned the throttle body and ICV and am not getting any codes. Inspected vacuum lines. Each cylinder is getting spark, compression was similar across the board. I ran the car and unplugged each injector one at a time as expected it ran like crap till I plugged each one back in. I’ve looked on here with lots of questions with no resolution to the repair. I took the timing cover back of to make sure the belt didn’t slip a tooth. Could the PCM be the issue. Any help would be appreciated.

99stockcivic

You could throw parts, or you can hook up a few tools and lets see what they say.

1 - Fuel pressure. hook up a pressure gauge to see what the fuel pressure is at idle and when you give it gas, this might tell us if it's a fuel pump or something related to fuel.

2 - TPS - hook up a multimeter to it and lets see if the voltage for the TPS is reading correctly from idle to full throttle (I think it should be about .5 volts at idle and 4.5 at full throttle.

3 - timing - Hooking up your car scanner what does the timing show when trying to accelerate

4 - clog in the exhaust? Perhaps the cat is melted from the overheating? Also what are the O2 sensors telling you?

5 - If you just keep letting it idle until it comes into closed loop , so fully warmed up, does it still die? At least eliminates cold start items then.

6 - Vacuum leak - I had an issue with an idle and it turned out that if you get under the car and look up between the axle and the intake manifold, you can see there is a vaccuum line under there, I know you said you inspected the lines, but this is one you can't see from above. It's directly underneath the upper intake, there is also a coolant line next to it. Make sure that hasn't fallen off.

That's some of where I would start. With the scanner, make sure all sensors seem to be doing something. Also...are you 100% all sensors are plugged into the right area? It's no uncommon for the things to get swapped as not all the plugs are unique.