I have a 99 civic ex d16y8 5 speed. runs fine and vtec works most of the time. every now and then if i get over 110 or stay in vtec range long i will all of a sudden loose power and not be able to rev over 5k and my check engine light will come on.this did not start untill i broke the oil pressure sensor on the vtec module,so i pressed the prongs inside the sensor together and it reads like it has the correct oil pressure at all times and like i said vtec works just fine most of the time. i come home disconnect battery for a while hook it up and then its fine again i have vtec and can run normal to 7k. also dont know if it has anything to do with it but if it is under 45 degree outside it is very hard to start my car and when it does start i have no throttle response at all will not rev at all just stays at a slow rough idle and runs like crap kinda like it is not firing on all cylinders and sometimes causes the check engine light to come on but not always . as soon as the car moves the temp hand it revs up then ideals right back down and runs like it never had a problem at all. if it is warm outside over 50 degrees i can hit the key and it runs like a champ. any help would be appreciated thanks.

 

No comment.

 

Actually, stop beating on your car. It's trying to tell you something.

 

By any chance did you think to check what code comes up from the cel before you disconnect the battery? That might give you a small hint to the problem.

 

Agreed. At least correctly fix what you know is broken before you do.

 

Takes 5 minutes and a paperclip.

 

I had a hard time making sense of this....

cliffs: beats on engine wonders why it doesn't function properly.

what codes tho should check that as soon as the light comes on. I always keep spare ones in my car

 

Can't tell if serious

 

I bought the car to play with it is not my only vehicle. i will go get a sensor tommorrow and change it but could this even be the problem seems how it reads that it has the right pressure all the time. for the time being how do i jump with a paperclip to read the codes. i have a full turbo kit i am waiting to put on but i want to fix this problem first. why did honda put vtec way up at 5500 it it wasnt built to handle it. i am just asking i am new to tuners and would like advice from more experienced people thanks for the replys. i am also new to this whole forum thing so dont quite understand how to use it yet.

 

Yeah. The fact that you beat on a grocery-getter like it's a racecar and have known deficiencies that you failed to fix has nothing to do with the malfunctioning car. It must be those damn Honda corporation engineers not knowing where to stick that tricky VTEC crossover in at.

How to pull codes.
https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/how-pull-cel-d4-srs-abs-codes-code-lists-1901557/

 

lol you can't be serious with that. are you suggesting you know more than the engineers at Honda

 

ok i never said that is not the problem all i want to know is how that could be causing it. and by the way supposedly the bottom end was built by the previous owner with eagle parts not sure what. i plan on doing some kind of swap maybe b18 later this summer but i wanna be able to drive it till then . is the d16y8 not worth building to be a race engine i planned on maybe building it as a spare engine later on but everyone refers to it as a grocery getter just wondering why. would that have anything at all to do with cold start since that is a vtec sensor not for cold start. i was wondering if it can be something else other than that pressure sensor or if the two could even be connected in any way.

 

i never said that at all. i am asking questions because i dont know not because i already know the answer. but that dont answer the question why put it there if it aint made to be ran that hard?

 

or am i wrong and that not the only place it kicks in.

 

1: check codes
2: fix problems related to codes
3: ????
4: VTEC

 

if you take proper care of the car sure you redline it no prob but that engine is not meant to have sustained RPM's of 5.5K+ for long extended periods of time.

 

yea i drive the **** out of it but i do maintenance on it constantly but i understand it a little better now....so what swap do you suggest me do to be able to run hard and be able to handle it. like i said i have a full turbo kit but if its gonna blow up in a week because of 7psi i will go ahead and do the swap before i boost it. and if i do a swap i want to be able to run around 15 psi safely

 

Well no engine is really supposed to be beat on even if properly maintained. I think you'll need to read up more on swaps and boost before you decide 15psi ? not on a stock engine....get ready to tear into the bottom end

 

You don't base a turbo build on how much psi you run. You pick a horsepower goal and find the parts that will get you there. 15 psi don't mean ****. Different turbos flow different amounts of air at the same psi. Looks like the search function is going to be your new best friend.

 

alright thanks but if thats the case like i said the bottom end of this d16 has been built. And is it possible to go k series in this car. i have no problem doing the bottom end i want to build the whole engine before i install a swap i have the funds to do it i just am looking for whats going to produce big numbers. i have big expectations because i drive a completely built 2001 ws6 pretty much daily like i said i am new to tuners. but thanks for the help i will do some reading on swaps now before i do it.

 

yes i know that with the psi i probably should have said around 400 hp

 

you didn't listen to anything he said.....

 

Well if you do have the funds K-Swap> don't trust what someone said rip it apart and see for your self