Hello, and excuse me for my english in advance. The car is 2002 Honda Accord 1.8l, 157.000km, engine code is F18B2. Manual transmission. The problem is, that my car jerks/hesitates when I fully depress gas pedal and then floor it. It does not matter if the engine is cold or hot. The car violently jerks a few times, then accelerates normally. It happens at any rpm. It is more felt in low gears, less in high gears. Another thing is, that when i try to keep constant speed in low gears (1-st ant 2-nd at 1000-2500rpm) it hesitates and it's hard to drive in traffic jams, because i have to use the clutch very often. Idle is a bit rough, engine seems to misfire from time to time. When cruising at high speed nothing wrong is felt. Also if changing gears very softly and not accelerating hard everything is almost o.k., almost no jerking/hesitation is felt. CE (MIL) light is NOT on. Changed: air filter, fuel filter, plugs NGK, wires NGK, cap/rotor/coil, then tried another distributor from salvage yard. Nothing changed. Cleaned EGR valve and ports. Did put in the new O2 sensor (NTK). Did the valve adjustment. PCV valve is O.K. Tried disconect any sensor that is present in this engine (TPS, MAP, IACV, IAB, EGR, KS, so on), reset the ECU/PCM, then test drive - nothing changes or gets worse. Cleaned IACV. TPS reads 0.5V at closed throttle and 4.5V at WOT. Voltage transition is smooth. Tried another MAP sensor. No luck. Engine idle rpm 's are OK, they do not jump around. Compression in all cylinders is 14.5-15bars. No white smoke, coolant level is constant. Eats some oil, but the eating rate is constant and it allways ate some oil. Ground wires to the engine are cleaned and ok. No vacuum leaks I did found. Maybe somebody here knows the solution?

 

How about the EGR port (if your accord has an EGR valve)?

 

He said he cleaned the EGR valve & ports. But isn't there different parts to those EGR passageways? I'm not sure how much different they are (F18B2 vs. F23A1).

 

EGR system is 100% o.k. Valve is clean and operates normally, passages and holes to the intake manifold are cleared and clean. I even tried to block it, but that had no efect on jerking too

 

Sorry, I missed the EGR the first time I read the post.

Is your EGR valve controlled electronically or by vacuum?

Check for codes anyway.

 

Electronically. Scantool shows no codes too

 

Blocked EGR completely. Nothing changed

 

Maybe check the mechanical timing of the engine. Get the crankshaft to TDC and check that the cam is to TDC? Or test the timing using a timing light.

 

Timing was checked with scan tool, it showed 12 degrees at idle, as it should be. Timing is controlled by ECU only, distributor does not rotate

 

No I think PA is suggesting that you check the mechanical timing. That's the timing between crankshaft & camshaft. That's controlled by the timing belt.

Scan tool can't actually measure spark timing. It can only display what the ECU is commanding. If you actually check spark timing with a timing light, you can see whether it agrees or not with that scan tool.