oldskoolaccord

just finished my LS/vtec setup on my Si and it ran great for about 3 days-now it seems to getting gremlins.....

1.I set the idle on the car and the timing mark lined up fine consistantly-but now the car changes idle eveyrtime I turn it on-somedays it will idle around 1k-somedays 1500-and others it will barely idle,could it be the stock Si ECU causing the problem?

2.Right around the waterneck area the headgasket seems to be leaking antifreeze-the cars not smoking or buring anything,in fact the radiator is full as well but it has a brand new headgasket and its all tourqed to spec?

3.theres 2 huge harness plugs that have no place to go,near the rear of the block-looked for something to lug them into but there is nothing-I am going to assume its a B16a2 thing?

the engine is a brand new 95 GSR head from dizzy to camshaft with a stock b18B block,its a 100% stock setup save for a blox intake manifold and GSR throttle body,any ideas woud help thanks!

Jackal6042

1. The ECU shouldn't be a problem there as far as idle.

2. Maybe it is leaking from the water neck. Pull it off, clean the mating surfaces and put some HondaBond on there. Clean the area under it well so you can tell if new coolant is leaking and it isn't just residual.

3. Let me guess, one is a single wire with a big black sort of shroud on it and the other one is a 2 pin connector? The single one is the oil pressure switch, on an LS-VTEC the oil pressure switch is usually on the oil feed line going to the head. Typically people will bolt a T connector to the back of the block. One side goes to the oil line, the other is for the oil pressure switch. The other 2 pin connector is for the knock sensor which you LS block didn't have so it has to be added.

Did you build this setup yourself or buy it built? Either way it seems some steps were skipped or jacked up. Check out this link and go from there.


http://www.c-speedracing.com/howto/lsvtec/lsvtec.php

oldskoolaccord

when I bought the car the person had built the LS/v by throwing a vtec on a LS block nothing more no head tapping no vtec oil line-so needless to say it was really messed up.

when I took it apart(this is my 3rd motor I have built first 2 ran like a champ)it had all sorts of different headstuds on it and the block was helicoiled-I reheilcoiled all the holes and installed ARP heastuds and added GE ls/v setup-I could have sworn it had a knock sensor on the back that I hooked up but will check again-oil pressure through my mechanical gauge is between 9~15 at idle and after 2500rpms it around 90+.

Jackal6042

WOW!!!! WTF!!! He must have thrown it together and just expected it to work. When you had it apart did you make sure the VTEC oil feed hole in the bottom of the head was plugged? I know this wont cause your idle issue, but it sounds like this kid you bought it from didn't know wtf he was doing.

Helicoiled block? Doesn't give me a warm and fuzzy but thats not saying it wont work for a while. I'd just periodically check the torque on those nuts on the head studs. At least until the helicoils settle in with the expansion/contraction of heating and cooling of the block.

Yeah check to make sure you have that knock sensor. But you said you had two plugs, is the other one the stock oil pressure switch?

If you don't have a Factory Service Manual for the teg I'd get one from www.pdftown.com. Your idle issues could be a few things. Have you checked the FITV and IACV and their respective inlets in the TB for clogging?

Personally, if I were you I'd pick up LS long block and start rebuilding it for whatever your planned future setup is because who knows how bad this kid you bought it from jacked **** up. But thats just me.