Engine will not go past 3,500 RPMs, sputters at 3,500 RPMs

1999 HONDA CIVIC

121,000 MILES • 1.6L • 4 CYL • 2WD • MANUAL

DAYDAYESCO

MEMBER
1 POST

The car cranks up fine. I recently did a swap from stock D16 to Vtec and started having this problem. Car sputters at 3,500 RPMs and won’t go past. I don’t have the Vtec wiring harness but figured it’d run the same without. Let me know what you think the problem might be.

Mar 13, 2022 at 8:01 AM

JACOBANDNICKOLAS

✓Experienced Mechanic
110,240 POSTS

Hi,

The idea behind a Vtec engine is to change valve timing and valve lift based on demand and RPM. In this case, you have an engine designed for computer-initiated change that doesn't happen at the higher RPM operations. The Vtec is designed to create a smoother running and higher-performing engine. At higher engine speeds, the cam profile allows greater valve lift, which allows more air into the cylinder. Thus, the engine is able to create more horsepower

Based on different inputs, the ECU is programmed to switch from the low lift to the high lift cam lobes under specific conditions. And yes, oil pressure plays a role in this as well. However, in your case, the ECU isn't able to do that which is causing the higher RPM issues.

Let me know if that helps or if you have other questions.

Take care,

Joe

Mar 13, 2022 at 11:31 AM

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