dozer451

So, I'm a first time poster, but I have sought answers to many a problem on here, and found helpful solutions. Ok, so here we go...

Back story-- I replaced the engine and transmission in my 94 Accord LX with a JDM F22B2 / xmsn combo from H motors, after my girlfriend borrowed my car and continued to drive it after the radiator blew, and roached the engine. In the process of replacing the engine I have done the following: replaced the radiator, heater core, engine mounts, and on the newly installed engine replaced the water pump, timing belts, camshaft seal, and spark plug tube orings. I transferred over my old intake manifold, exhaust manifold, distributor, fuel rail, and wiring harness from my old engine to the new engine.

Upon start up on the new engine, I had flashing D light for the CSS sensor on the xmsn, so I swapped it over from my old xmsn, and it went away. The car idled perfectly when cold, and drove perfectly, but after the car was warm, the rpm dropped below 500, stumbled and died. Eventually it threw a code 14 CEL.

I picked up a used IACV that was cleaned and installed it, no love, still had the same problem once the car was warmed up, same 14 CEL. I then picked up a used throttle body with the map sensor, TPS, and fast idle valve, and installed it. The problem remained, but I no longer had a 14 CEL indication, it changed to a 12 CEL.

I then picked up and installed a new EGR valve and it still had the same problem, so I replaced the EGR vac solenoid control unit assembly. Here is where it gets messed up...

After the vac solenoid replacement, the problem went away completely for a 15 min test drive, after the car had already been warmed up. I thought to myself cool, finally found the problem, so I reinstalled the old EGR valve, so I could return the new one. (thinking the solenoid assy was the only problem). I test drove it, and the problem came back, but no code was given. I then reinstalled the new EGR valve that I just removed and the problem remained.

Here I now lay at my wits end. The engine runs perfectly as long as I'm not at idle. The original idle stumble and subsequent stalling, once the engine is warm, remains. However, I am not receiving a CEL now. I have driven the car, trying to get the CEL to come on, but it won't. I have to feather the pedal at idle to keep the car from dying.

I have already cleaned the EGR ports. The coolant system is sufficiently bled of air. I have checked for vacuum leaks and I can't find any, nor have I been able to find any bad wiring connections. I have searched high and low in the forums for answers, and I cannot find anything new. I believe it's something to do with the EGR system, since it went away after I replaced the vac solenoid assy, initially. I'm very mechanically inclined, but I need help with this. Any help would be greatly appreciated.

Lost Again

Try pulling the vac hose off the egr valve and plug it. Start the car and let it warm up, is the issue still there? It is easy to get a vac hose switched when replacing the motor (seen it so many times it is not even funny anymore). If the idle is good at idle when warm with the hose off the egr let us know and we can give you the possible two places these get switched.

dozer451

I will try that once I get home, but I'm very confident that I didn't get the hose switched. I have traced it all the way back to the vac control solenoid.

hoopty hopper

Sounds like egr heres some info might help...
Inspecting and Servicing the EGR System
The EGR system is intended to reduce the amount of oxides of nitrogen that are formed during combustion. The introduction of exhaust gases reduces the combustion temperature, which in turn lowers oxides of nitrogen. EGR systems normally are not active on engines when cold, at idle, or at WOT. To inspect and service the EGR system, start by researching the description and operation in the service information. Then perform an output test on the EGR valve. With either a scan tool or a vacuum pump (depending on the system; refer to the service information on testing), operate the EGR valve with the vehicle running. Idle should become rough, and the engine may eventually stall as the EGR valve is opened and exhaust gas flows into the intake manifold. If the idle becomes rough, the EGR valve is capable of operating and the passageways are relatively clear. If there is no change in the engine idle speed when the EGR valve is activated, perform testing of the control system to ensure that a signal is getting to the EGR valve. This could be a vacuum signal or an electrical signal, depending on the type of EGR control system. If a signal is getting to the EGR valve, inspect the valve itself for faults and the EGR passageways to ensure they are not clogged.


I know it might sound off subject but how are your shifts for your trans? I just had similar issues with hard shifting, idle was rough, and it would stall out from time to time while the engine was warm,it would shift at odd times,hated going uphill and eventually got to a point when as soon as it got to operating temp stalled out after coming to a complete stop and wouldnt start until engine was cold,i replaced the torque converter now everything is all honky dory.