My question is what problems or sensor issues will I run into putting a non Vtec engine in a 04 that was a Vtec? I have a 2004 Honda Civic EX 1.7l Vtec and the engine took a ****. I bought a engine with only 100k miles and it’s not Vtec haven’t put it in yet I’ve ordered water pump and timing belt waiting for them to come in. My question is what problems or sensor issues will I run into putting a non Vtec engine in a 04 that was a Vtec?

 

If you get a non-VTEC ECU... nothing.

 

Thats the thing…The ECU in the car is for a Vtec and I’m putting a non Vtec engine in it. So would I have to spend $800 to get a non Vtec ECU? Or can I get away with just not plugging up the Vtec sensor

 

I fully understand what ECU you have in the car. If you try and use the VTEC ECU in the car with a non-VTEC engine... you would OBVIOUSLY not plug up the VTEC Solenoid and VTEC Pressure switch plugs on the engine harness because there is nothing to plug them into on a non-VTEC engine. However, the VTEC ECU is looking for these sensors, will detect a fault, throw a "Check Engine" light, and the engine will go into a protective mode and not run correctly at all.

So, as I stated before... you will need to replace the VTEC ECU with a non-VTEC ECU. The good news for you is that you will NOT have to spend $800 for it... they are found in junkyards all over the Country for cheap. You will likely spend more $$$ to have it programmed to your key and immobilizer than you will for the ECU. Yes, it will cost a few hundred bucks... but this is the ONLY way it will run correctly.