dc2_dude

hey guys im posting up for a friend. he has a 99 gsr integra with a b20b/b18c1 swap.
He bought the car how it is for a great deal from a dealership not knowing anytthing about it.

he brings it to me and says my vtec isnt working. So i checked the oil lines etc.coolant level,oil level,no check engine lights.. and then to the ecu. it has a p73 obd2 ecu for one.

anyways i took the vtec soleniod off and cleaned the screens and gaskets off. put it back together took it for a drive and it worked. on the way back to our car meet, he drove it and it didnt work. we let the car sit for 10 min. tryed again and it worked, then on the way back after turning around it didnt work????? im lost

only thing i can think of is loss of oil pressure, because it was kicking in late. .like around 6-6300 rpms. and with a skunk 2 I/M and a ITR ecu it should be around 5200 rpms

any suggestions???

dc2luver

I Know type r's vtec engages later beause it revs higher rpms. does this ecu have any type of tuning software on it?

dc2_dude

not that i know of.but im pretty sure its obd2 so it cant.

mouab18c1

iTrader: (5)

Check for loose wiring

dc2_dude

thats not it i did. after the car starts warms up..drive it.. hits vtec..slow down turn around in a parking lot..let it sit for a min. make another pull no vtec..every single time. every time he lets the car sit for a while then start it up hits vtec..then 2 min. later it doesnt. there for im thinking oil pressure??? idk confuses me

ExtraBlackRex

Oil pressure would be a Good thought...if it's not right at the time of engagement it won't hit, wont throw a CEL Light either (At least i've seen it happen). Have you tried using another ECU?

dc2_dude

no i told him to find someone with a p72 just try it. and if thats the problem i told him to get a jumper harness and go the p28 route.

and to get a oil pressure gauge asap. its weird the car runs great!!! just no vtec all the time. and im sure it would be a pretty quick car. im just trying to help him out because he bought the car the way it is and hes only 17 so he knows nothing about honda's yet.

ExtraBlackRex

Keep Oil pressure as a possibility, but until then I'd try another ECU and see where it gets you.

dc2_dude

yea im gonna have him try that first. just makes me mad i couldnt figure it all the way out for him haha.

Cman46290

And your sure the Vtec solenoid itself is ok?

dc2 b20vtec

i think u should check your wiring bro it sounds like a wiring problem

dc2_dude

nope checked it for shorts for him and everything was good, vtec solenoid is good. just waiting for him to get a oil pressure gauge so i can narrow it down

racebum

too many reasons to even count


1. if it's a usdm p73 you need

a. cfs sensor
b. knock sensor
c. vtec solenoid with oil pressure

2. if it's a jdm p73 you need

1. knock sensor

in all cases you need the wiring strung for the correct sensor

one more thing, a p73 only works on a 1.8L engine with itr cams and a single runner manifold

you do not have this thus you have the wrong ecu for that engine.

dc2_dude

yea when he first got the car he showed me everything that was done. then told me vtec wasnt kicking in. so first thing i checked was what ecu...p73 everyone was like so what..i said well that wont work unless you have all of the above^^ he does have a skunk2 manifold..but as far as engine internals are im pretty sure there stock but i have no clue. he got the car from a dealship and they knew nothing about it. He hasnt got the title yet from them or anything i told him to tell the dealership he needs to speak to the previous owner about everything done.

only things i know are

b20b block
b18c p72 head
s2 cam gears
s2 manifold
aem fuel filter
golden eagle fuel rail
aero fpr
i/h/e

friday im going to his house to pull the valve cover off to see what cams. and pull the ecu to see which p73 it is. how can i tell if its usdm or jdm??

also where are the knock sensors located on a b20?

also is there a way to tell if its a gsr harness.
the car is originally a 99 ssbp gsr.

racebum

i'm not even sure if the b20 has a knock sensor that's compatible with the p73, it's disabled in many obd1 custom maps because people don't tap the blocks to fit the correct one.

when you look at the ecu you'll see p73-a02 or3 or 4 if it's usdm, jdm is p73-003 or 4

of all these p73-a02 is the most sought after

p73-003 and 4 are the easiest to get running since they don't require the usdm sensors or even need a post cat o2

all are wrong for any b20

Robinjo

I would look at the oil pan, make sure it's not dented inward. I had a similar problem, intermitant VTEC engagement and it turned out to be the oil pan.

As for the knock sensor, don't they make a sensor delete for that? I thought I heard of a device that tricks the ecu into thinking there is a sensor there....

Best bet on the ECU is to run a tuned unit. Crome, Uberdata, Hondata, whatever but get it set up properly!

dc2_dude

alright ill tell my buddy what he needs to do. i told him to get the money to me and ill make sure he gets the right stuff. i was just gonna get a a 0bd2 to 0bd1 jumper harness and a p28. then have it tuned/chipped on crome. or s300

racebum

why in the world would you spend so much on an s300 for such a simple setup? the s100 can easily control that engine.

dc2_dude

hey its not my car man hes got money!. well icalled him today he said he ordered a chipped p28 with jumper harness. He said he told the guy his motor and mod setup and they would tune it to those specs with a re burnable chip. so hopefully this works out for him

racebum

tuner shops constantly take advantage of idiots. which hondata they sell is only one place. the s300 has the biggest margin and the highest profit per sale. useful in some apps but overkill in many.

dc2_dude

yea idk where he got this "pre tuned" ecu. i told him just to get stock p28 and i would base map it on crome i have the softwear. but he spent 290 dollars on this random ecu thats chipped with a jumper harness and a 2 step. probably ebay. whatever. Thats what happens when a 17 year old kid gets 6 grand and guys out and buys a bad *** ssbp gsr