5th gen Prelude boosted issues

granturismonut · Post by **granturismonut** » Tue Apr 17, 2007 4:14 am

I'm posting this for a freind of mine that's not online, and I'm new to this fmu/missing link stuff so bear with me.

He has a 5 gen Prelude, he bought it from a car lot and has no prior history on the car. From what is visable it's running a FMU and a missing link. He said that Vtec isn't that noticable and don't know if it's operating, (I know that on my turbo B series that vtec is very noticable). and on cold mornings before it's warmed up fully about the time vtec should come in it feels like the rev limiter cuts in.

So my questions besides those above is, what are the tuning options for OBDII H22's, and is there anything I can double check? Oh ya he only running 5.5 psi.

Thanks in advance

b18b-t · Post by **b18b-t** » Tue Apr 17, 2007 6:54 pm

you have a turbo b, so you should know that the fmu and missing link should be tossed in favor of some sort of real engine management software. I'm not sure whats available for for the h series but im sure the obd2 will need to be replaced by an obd1 ecm. pgmfi.org and the other honda enthu sites will give you extinsive insight to this problem. And why is the motor being reved/pushed that high when it hasnt even reached full operating temp? Thats risky business

JustRob · Post by **JustRob** » Wed Apr 18, 2007 7:04 am

Take the FMU and missing link and destroy them so no one ever uses them again. Go to jhpusa.com or rywire.com get an OBD2 to OBD1 conversion harness and pick up an OBD1 ECU. A P13 ECU would probably be best, but you can use a P72, P28, P30, P61, P08J, P30J, or P72J too. Then pick up the Hondata S200B or S300 and get the car tuned right.

As far as VTEC goes, do not expect to get VTEC before the motor is warmed up. The computer won't let it happen. What your describing is exactly what the car is supposed to do. If it isn't working properly after the car is warmed up, check your oil. If theres not enough oil in the motor, there won't be enough oil pressure for the ECU to kick VTEC on. If that doesn't work, check and make sure that it is wired in correctly. Then I would check the solenoid gasket and and filter.

And as far as tuning goes, the only thing you can do with the OBD2 ECU is a piggyback. Your better off converting back and getting Hondata as I said above.

evoman33 · Post by **evoman33** » Wed Apr 18, 2007 8:04 pm

where are you located? maybe i can help tell him to pm me. i had a 89 b16a and the vtec wasnt working properly and its a very simple problem to fix.

RideMyKlutch05 · Post by **RideMyKlutch05** » Wed Apr 18, 2007 11:15 pm

You gotta pay to play when turbo-ing Hondas. Do it right the first time and don't use those crappy pre-tuned engine management chips. Get an AEM EMS, Greddy EManage Ultimate or atleast a Hondata S200 w/boost...

granturismonut · Post by **granturismonut** » Thu Apr 19, 2007 1:57 am

ok, so from the look of things the best bet is going to be to go with Hondata s200 w/boost with a OBD2 to OBD1 conversion using a p28 and 440cc injectors.

Where would you recomend getting it tuned? I know there are a few shops people would rather go to, and other people would rather stay the hell away from.

And the vtec not engaging was more of a knock sensor question, sorry if I worded the question wrong, in the mornings when it's colder outside it does it rather than when it's warmer in the afternoon.

Yes I know very well that to play you gots to pay, but when he bought the car he thought he was buying a car that needed no further modding. and convincing him to do things the right way the first time around is sinking in after I told him what I went through with my car.

Thanks for the help guys

JustRob · Post by **JustRob** » Thu Apr 19, 2007 2:31 am

Sounds like a good choice on the engine management.

If your wanting a local tune, go to Lowe Performance. I've seen really good numbers from them and my car will be headed there probably in the next week or so. If you want to go all out, call up The Whip Factory and have Dave tune it. As far as the midwest region goes, he puts up the biggest numbers for Honda/Acuras. Not only that, but the cars that he tunes run extremely well. Whatever you do, please stay away from Adrenaline, I think you know why.

So is the motor completely warmed up when the VTEC issue is happening?

granturismonut · Post by **granturismonut** » Thu Apr 19, 2007 3:10 am

Super Dave tuned my turbo B16 and I couldn't be happier, but pending his making another tuning trip to Stl. I'll recommend Lowe Performance.

Yes the temps are up to normal when this is happening. Kinda why I was thinking maybe a bad tank of gas and lower air temps in the morning causing a knock and not letting it enter vtec.

b18b-t · Post by **b18b-t** » Thu Apr 19, 2007 6:16 am

what can lowe performace tune with for hondas?

JustRob · Post by **JustRob** » Thu Apr 19, 2007 6:45 am

b18b-t;37102 wrote:what can lowe performace tune with for hondas?

I know they have done Hondata and A'PEXi. I think they are willing to tune anything to be honest. They didn't know how to tune the Power FC until 99BlackHatch took his car there.