VTEC ENGINE HESITATES DURING ACCELERATION
TECHNICAL SERVICE BULLETIN
Reference Number(s): HSN 0402-07, Date of Issue: April 2002
HONDA:1994-2002 Accord; 1992-2002 Civic; 1993-2001 Prelude; 2000-2002 S2000, Insight; 1999-2002 Odyssey
CATEGORY:Honda Service News
APPLIES TO:1994-2002 Accord - All with VTEC; 1992-2002 Civic - All with VTEC; 1993-2001 Prelude - All with VTEC; 2000-2002 S2000, Insight - All; 1999-2002 Odyssey - All
Related Ref Number(s): HSN 0402-07
NOTE:This article applies to '94-02 Accords with VTEC, '92-02 Civics with VTEC, '93-01 Preludes with VTEC, '00-02 S2000s, '00-02 Insights, and '99-02 Odysseys.
If your customer complains that the engine hesitates briefly when accelerating, chances are the ECM/PCM is ordering fuel cutoff because of low or delayed engine oil pressure to the VTEC system. Typical causes for low or delayed oil pressure are low oil level, a dented oil pan that's touching the oil pickup screen, or some other oil flow restriction.
When the throttle opening, vehicle speed, engine coolant temperature, and engine speed indicate that VTEC is needed, the ECM/PCM turns on the VTEC solenoid valve.
Oil pressure should immediately turn off the VTEC oil pressure switch. But if the switch stays on (because of low oil pressure), the ECM/PCM orders fuel cutoff and shuts off all the fuel injectors. Normally the ECM/PCM turns on the MIL and sets DTC P1259 (VTEC system malfunction). But if the oil pressure switch turns off before the ECM/PCM sets the DTC, the engine hesitates and then runs normally.
To fix this engine hesitation, troubleshoot the oil level or oil supply problem.
Monday, October 12th, 2009 AT 7:02 PM