Patient: 1994 Honda Accord LX with 185,000 miles

Symptom: Upon acceleration ONLY after sitting for a long period of time (overnight and at work), car sputters, bogs, and generally does not want to accelerate. Dangerous because it's doing this on a busy bridge where people are up my butt. Once car is warmed up and accelerator is floored, does it finally perform correctly.

Treatment so far: New plugs and plug wires, new PCV Valve, new fuel filter, timing belt replaced at 182K, and fuel treatment (additive) added last fill up.

Stuck - Please help.

 

When did the problem start? Before or after the timing belt change?

 

After

 

Sorry - 6 Months after

 

Well, that blows my theory of EGR vacuum hoses connected wrong. EGR only works when the engine is warm. There are four EGR ports on 5th Gen engines and if two or three of them get clogged then the fourth, unclogged one gets too much EGR, resulting in bucking/bogging at ~1750 - 2250RPM, cleared up when the engine is floored. But not on a cold engine.

Compression OK?

 

Does check engine light ever come on and stay?

Does light come on for 2-3 secs when keyswitch is first turned to On, then go off?

good luck

 

Check Engine light only comes on upon start up and goes off immediately like it should. It has never been on stedy in the 12 years I 've had the car.

I've not had a compression check, but the EGR is something I can look into. I can happily say that it did not act up this morning.

Is there any way to counteract the 10% ethynol gasoline damage that is being done on these older engines?

Thanks again for everything.

 

You're reading too much political press. There have been scare stories lately started to alarm folks about 15% ethanol, which indeed may have some adverse effects. 10% ethanol has been in gasoline for many years now and any significant adverse effects would have been apparent. I removed my 94EX fuel tank a few years back to replace fuel pump and was amazed at interior. It looked new!

Are you losing any coolant? A leaking head gasket can sometimes cause rough running for a short time after cold start, and a more severe leak might cause more serious roughness.

Suggest inspecting carefully for intake air leaks; damaged or missing vacuum lines. An inspection for intake vacuum leaks using throttle body cleaner sprayed on idling engine is another option. Check injector base orings for correct seating/seal.

good luck