help with setup, can't hear VTEC

[1caintegra]

ok one of my buddy was telling me my type-r intake manifold would be the reason why i can't hear vtec. is that tru i was think it was a vtec solenoid. thanks

 

[Ominous G2]

So you have a Gsr with a Skunk2/blox type-r IM?

 

[Ominous G2]

ITR manifolds dont bolt up to a P72 head.

 

[TegSox]

Well, if the VTEC solenoid is broken and not engaging VTEC, then you won't hear VTEC.
So you modified a Type R IM to fit on a GSR head?

 

[1caintegra]

So you have a Gsr with a Skunk2/blox type-r IM?

ya that what i got

 

[Ominous G2]

Check your oil level too.

 

[Backwoodz Tuner]

Well you should be throwin some type of error code, is your check engine light on?

 

[end005]

vtec won't engage if your oil pressure is low. but I bet you knew that.

 

[99Geezer]

VTEC Control System, Troubleshooting Flowchart


Check VTEC control system:
1. Reset the ECM
2. Start engine
3. Let it warm up
4. Do "road test" which consists of driving at 6000rpm for at least 2 seconds. Repeat two more times if no CEL.

I got the CEL again, moving on...



Test VTEC pressure switch:
1. Turn ignition off
2. Disconnect VTEC pressure switch connector
3. Check for continuity between VTEC pressure switch connector terminals.

There is continuity, pressure switch OK, moving on...



Test VTEC pressure switch wire:
1. Turn ignition to ON (II)
2. Measure voltage between switch terminal 1 and body ground

I got battery voltage, wiring OK, moving on...



Test VTEC pressure switch wire:
1. Measure voltage across switch terminals

I got battery voltage, wiring OK, moving on...



Test VTEC Solenoid Valve:
Well this part of the process has to do with checking oil pressure reading, however I can't really do that right now as I don't have the necessary gauge & adapter to attach it. So I'll say that it is likely to be okay as I always do regular oil changes, am using synthetic oil, the level is within spec, and it has a reasonable number of miles on it. But, to be safe, and assume that it's not, the action to take is "Inspect VTEC solenoid valve" which I did do and it looked fine from what I could tell -- the valve moves freely and the filter screen isn't dirty.

Moving on...



Test VTEC pressure swtich:
1. Turn ignition off
2. Reconnect VTEC pressure swtich connector
3. Start engine
4. Connect battery + terminal to VTEC solenoid valve, measure voltages at ECU connectors.

Got battery voltage over 5000rpm as expected, moving on...



Test VTEC solenoid valve:
1. Turn ignition off
2. Disconnect battery + terminal from solenoid
3. Check for continuity between solenoid connector terminal 1 & ground.

Is there 14-30 ohms? No, mine reads about 40 ohms. Action is to replace the VTEC solenoid valve. So I got a brand new one right from an Acura dealer, which measured about 15 ohms...much better.


Well after replacing that, things are a little better, it doesn't click on/off like it used to. However, it still cuts out sometimes, so there is still a problem!



Test VTEC solenoid valve wire:
1. Check for continuity between VTEC solenoid conector terminal 1 & ECU.

Got continuity, moving on...



Test VTEC solenoid valve wire:
1. Check for continuity between VTEC solenoid conector terminal 1 & ground.

No continuity, moving on...


At this point, the only other thing it suggest is swapping out the ECU itself!!! Well I don't have a spare ECU just laying around, and damned if I only know one other person who has a compatible one...I'll have to see if I can convince him to let me borrow it for a bit.



So now that I've typed up this novel, and you've read it (wow!), I guess the point is that I am really running out of ideas as to what the problem could be. I'm interested in what suggestions others who are more versed in the internal behaviors of the VTEC system might have to offer.

See if this helps

 

[kcombs]

^damm.

 

[TypeR?]

to the OP, are you running the stock p72 ecu?
from my own experience most gsr owners can not hear the vtec crossover and never know when it actually happens.
what you think is "vtec" is actually your iab's(secondary butterflys) at around 5500-5700rpm in the stock dual stage intake manifold. actual vtec on a stock gsr is at 4400rpm and once you upgrade to a single runner mainfold (i.e. skunk2 or blox) you will no longer hear vtec "pop" unless you get your ecu chipped/tuned and move the engagement point up in the rpm range.
hope that helps

 

[99Geezer]

to the OP, are you running the stock p72 ecu?
from my own experience most gsr owners can not hear the vtec crossover and never know when it actually happens.
what you think is "vtec" is actually your iab's(secondary butterflys) at around 5500-5700rpm in the stock dual stage intake manifold. actual vtec on a stock gsr is at 4400rpm and once you upgrade to a single runner mainfold (i.e. skunk2 or blox) you will no longer hear vtec "pop" unless you get your ecu chipped/tuned and move the engagement point up in the rpm range.
hope that helps

I bet thats what it is, mistaking the iabs for vtec. I use to think the iabs was vtec when I first got my gsr, and i'm sure im not the only one. Listen really close at 4400, no radio, no nothing. Still if you believe your vtec is malfunctioning, let us know

 

[1caintegra]

thank guys ill let u know what happen the ecu im runing right now is a stock p72

 

[TypeR?]

thank guys ill let u know what happen the ecu im runing right now is a stock p72

well there you go, your vtec engages at 4400rpm and is pretty seemless so you shouldnt be able to hear it8)

 

[1caintegra]

well there you go, your vtec engages at 4400rpm and is pretty seemless so you shouldnt be able to hear it8)

are u say o wouldent. be abull to hear it?