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Car not pulling, feels slow and sluggish

Just a thought, but does VTEC still engage? I think you said earlier it does engage but doesn't seem to give the power which is normally expected, yet will still rev to 8300rpm...

I-VTEC gives the extra power by not only swapping to the higher-profile cam, but also alters cam timing via the VTC system.

I'm starting to think it may be the variable advance of the intake cam which isn't working properly. The brains to this lie in the VTC system - which consists of a computer controlled, oil driven adjustable cam gear.

Looking at the schematic below, there is a solenoid valve which is fed via an oil strainer. Its likely that if this failed it would stop the whole system working correctly.

i-vtec.gif
 
Well i cant hear the changeover .... it feels like its trying to engage if it hasnt already....and yes it will rev to 8000 revs. I thought if there was a fault with the VTEC system it would not let you rev about 5800 revs?
 
I believe that if the VTEC doesn't engage for some reason (i.e. low oil temp) the engine will still redline. I've seen that happen with a friend who had once low oil and also once with low oil temp. The vtec changeover just doesn't occur (no 'jerk' almost) and the revs just keep building up anyway, with less perfomance. No limiter kicked in!

I've read how the solenoid can break sometimes, ECU signals it to do the changeover - however the solenoid won't and therefore you get less power and no changeover.
 
Well in 1st through to 3rd It definetely feels like something is happening in the VTEC range.. It feels like there is a hint of pull and it does accelerate a little quicker. But I cannot hear the engine note change and neither can my mates who all have civic type R's and I have an AEM short RAM intake with a 5Zigen Pro Racer exhaust. My 6th gear however, does not engage VTEC at all. After doing 8300 revs from 5th gear it drops to 6000 revs in 6th and does not go beyond 6200 maybe. But it does not reach the REV limiter neither. It just seems like its maxed out.
 
Yea the engine will still redline if the VTEC doesn't kick in but the performance will be pants. It could well be that the higher-profile cam is still engaging but the cam timing isn't advancing as it should.

The problem you are describing does sound as though its related to the VTC system somehow - its most likely the oil pressure/temp sensor which has failed or the VTC solenoid. There is also a VTC spool valve assembly IIRC.

As to how you would narrow these down, easier said than done as they all would have an effect on VTEC functioning correctly.
 
These may be of help (they maybe for the K20A3 block though but PNs will be similar for K20A2)

Civic 03-05 VTC Spool Assembly P/N: - 15810-RAA-A01

Civic 03-05 VTC Oil Control Assembly P/N: - 15830-PNC-003
 
you guys wouldn't believe this! But after cleaning the air filter my car is back to the beast it was!! I couldnt believe it because when I was cleaning the air filter hardly any black stuff came out, but I did notice that the water wasn't going through the filter until a few rinses. Now the car is pulling very strong once again and in the vtec range. It just wasn't breathing right and hency running rich. I still have a bit of a flatspot pulling off but it is so small compare to what it was before. Maybe the inlet manifold might need some cleaning! But thanks to all you guys for all the help.
 
doc_loco said:
you guys wouldn't believe this! But after cleaning the air filter my car is back to the beast it was!! I couldnt believe it because when I was cleaning the air filter hardly any black stuff came out, but I did notice that the water wasn't going through the filter until a few rinses. Now the car is pulling very strong once again and in the vtec range. It just wasn't breathing right and hency running rich. I still have a bit of a flatspot pulling off but it is so small compare to what it was before. Maybe the inlet manifold might need some cleaning! But thanks to all you guys for all the help.
Click to expand...

The first thing I suggested in post #2 :rolleyes:
 
Been following this thread (although with no input as I'm completely clueless :eek:) and so glad you got it sorted mate must be a relief?! Inconrovertable evidence though that Honda main dealers are bobbins!!

:lol: lottie
 
Absolutely... How nobody could tell me anything was amazing. Had friends, local garages, honda garages. It was only when I saw the posts on here that I thought why not give this a go because I had nothing to lose. Feels like a new car again :) Bloody AEM filters! LOL.... now time to clean intake manifold when I get the time!
 
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