ok i have a 2000 Prelude and I've been having problems with my vtec for a long time. When I got my lude someone had tried to take off the vtec controller and didnt do a very good job and left the wires exposed so it was shorting out every once in a while during vtec engagement. I had it down at the tracks one time and hit the rev limiter pretty hard in 1st and it shorted out again. So i took it down to a performance shop and had then reinstall the VAFC but my vtec wouldnt engage after that. If i go past 5400 rpms my vtec tries to kick in and i can here it but i feel no difference and then i hit a limiter and 6400 rpms and my cel comes on and gives me a p1259 code. I took it to Honda and had them check the solenoid and pressure switch and they said they were both fine and the mechanic said there is nothing wrong with my engine the vtec just wont kick in. So I was wondering if there was anything i missed ... my mechanic also said I was building a lot of pressure in the radiator and my head gasket might be blown...could this be the problem?

 

if your head gasket was blown youd be smokin alot....

but i had a similar problem with mine after getting the head machined and the shop forgot to install the oil control orifice under the intake rocker arms which gave me the feeling that vtec kicking in but it wasnt idk its hard to explain but i never had a code

but that code is the vtec solenoid not working properly and is why its only revving to 6400 rpms.....

you need to go through the wiring and make sure there arent any shorts or bad grounds obviously the guy that tried to take it out didnt fix the wires after uninstalling the vafc.

http://www.hondahookup.com/manuals/..... they have wiring diagrams and the service manual diagnosing process just scroll down and youll see the prelude sections.

 

it only smokes once i go over 5400 rpms cuz the ecu is messed up with the cel and its dumping fuel so no bad smoke really, and it was really weird cuz like 2 weeks ago one of the wires was loose to the vafc and my vtec actually kicked in and i felt the difference and everything and i took it back to my mechanic and he hooked up the wires and then it went back to not working again

 

it sounds like your vafc is not installed correctly. i would have teh shop that put it in re do it right htis time, and then when theya re done take it for a drive and if it doesnt work go right back....

 

the vafc is completely off now, we tried that to make sure it was nothing with the engine so theres no problem there. i may just get a whole new wiring harness and have honda hook everything back up, cuz engine wise i cant find anything wrong with it.

 

yea definately sounds like somethin is screwed up in the wiring.... try double checking the wires from the vafc to the ecu cuz if one of the wires jumped off and it kicked in maybe its hooked up to the wrong wire and interupting the signal from the ecu to the solenoid.

 

whenever i check the code it says -signal to pcm error p1259 and on a lot of threads they say thats the vtec solenoid but honda checked it like 3 times and they said its working fine so idk with that

 

could it be possible that maybe your ecu is bad after having the vtec uninstalled incorrectly and stuff maybe somehting happened to the ecu... just a thought but yea man i dont know thats really strange.

 

it may be and that would suck lol but I'm gonna check all the wires and make sure and if I dont find anything I'm gonna take it back to Honda again

 

yea if all the wires are ok see if you cant find someone to swap ecu's to see if thats the case hopefully not there expensive as hell.. good luck