Early revlimit and no vtec problem

We may earn a small commission from affiliate links and paid advertisements. Terms

S

stivic

Member
Hey guys Im not that good with this stuff so I could use a little help if possible I have a B18C swap in my civic EX the old motor was the D16 Vtec I've had a topic about this before but I think I may have come across some more variables that may result in the 7k revlimit instead of 8200 like it should.

I was looking at my ECU pinout tonight and found that the IAB wire which should have been switched from pin out A20 to A17 wasnt switched so I switched it however it still wont go past 7k... earlier this week i was testing my ECT (engine coolant temp) sensor and one of them only read .01 so I replace it with one I found in the garage it could be bad as well but i havnt got a chance to test it yet.

However following up the A20 to A17 pin switch Im not too sure if I plugged the EVAP solenoid plug under the GSR IM for the IAB it may as well be the plug i plugged in ontop which I think is the IAT (intake air temperature) sensor does anyone know could this cause a early revlimit and no vtec

I have no engine codes to check no loss of power or miss fire there is a distinct exhaust note change at 4400 RPM is that the vtec or secondaries
 
VTEC hits a 4400 on a GSR. Fuel cut should be at 8200 and redline at 8k. what ECU are you using?
 
sounds like your tach is off....

and you only have to move the IAB pin when your running an obd2 GSR intake manifold on an obd1 p72 ecu
 
The ECU is a P72 however it may be AUTO where as it says "AS" and I've noticed in alot of my friends 5 speeds their ECUs have "MT" instead which I am just guessing could mean MANUAL Transmission. I could be wrong though.

and if my tach were off how would that explain not having vtec
 
nightshift @ Oct 28 2005 said:
Quoted post[/post]]
does the honda ecu limit revs when the engine is cold???
Click to expand...

Yes. It's the same rev limit as when it's warm, however the ECU will not switch over to the high lobes before the engine is up to operating temperature. So even if you do somehow hit the rev limit while the engine is cold, you'll be able to tell as the regular lobes will make the engine fall flat on it's face around 5500 rpm and up.
 
I have a 97 gsr i had a similar problem with but i was throwin a code 22 (vtec malfunction) and it was rev limiting at 6500-7000rpm. I ended pulling off the vtec press. swith/ sol. assembly and they was a bunch of junk caught up in the screen thats in the ass. after i cleaned that and re-set the ecu everythin was cool.
 
Yeah see I dont have any codes though I've already checked the vtec pressure switch its good Im thinking it may be a ground problem somewhere
 
id check all three wires. if the switch isnt grounded or not running back to the ecu you are sol. if the soleonoid isnt wired back to the ecu you are sol. thats where i would start.
 
reikoshea @ Oct 31 2005 said:
Quoted post[/post]]
id check all three wires. if the switch isnt grounded or not running back to the ecu you are sol. if the soleonoid isnt wired back to the ecu you are sol. thats where i would start.
Click to expand...

All that stuff should have been already wired though because my old motor was the 1.6 vtec
 
fix your iab problem first. your activation ins't working and thats a big power bottle neck.

do that, run it around, see if it pulls good.
 
pissedoffsol @ Oct 31 2005 said:
Quoted post[/post]]
fix your iab problem first. your activation ins't working and thats a big power bottle neck.

do that, run it around, see if it pulls good.
Click to expand...

The IAB problem do u mean switch the pins back from A17 to A20 or whatever it is, I wonder why when I was asking questions about what i needed to do to the swap alot of people said knock sensor and IAB pin change
 
You must log in or register to reply here.
Back
Top