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Hi all,
I have an 04 SE with about 130k on it. I've had this weird issue for quite a long time where on a cold start (cold mornings mostly too) probably more than half the time you drive off in 1st or second adn you get to about 2,500-3,500rpm and its like the car hits a rev limiter, it doesn't pop or bang it but feels like its on a rev limiter - more throttle makes no difference - once the car is up to temp it seems to be fine pulls well etc.

I don't hammer the car when its cold this is just normal driving situations at cold start up - the car is standard bar an intake & nitro dann throttle body downpipe.

generally the car is pretty healthy, maintained pretty well.

cheers
Brad

It's not weird. Just an NB problem. Leads, coil packs.

sceptical, but no solution from me

I think Bruce is right. Mine use to do similar before I had the chip upgraded. Still displays some minor moments of hesitation when engine is cold but nowhere near what it was. From memory of posts I found online back then it was something to do with the way the ecu manages fuel (or I should say it doesn't manage it properly) until the O2 sensor warms up.

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yeah I was thinking its the hesitation thing but usually that is when the cars warm and you are at about 4krpm and it slightly bobbles in reves and moves on. .. this is like a rev limiter but good to know it could be that rather than something bad.

I'd love to do the chip/intercooler/exhaust and move on..... if I find one of those elusive trees with $100 bills on it I will hahaha..

will look into leads and coilpacks - don't think I've ever replaced those in the 4-5 hears i've had the car.

cheers

It just sounds like the VTCS is in the active position. There's butterflies in the intake manifold that block most of the airflow off to each intake runner that's supposed to be active for cold starts for emission purposes (I think?).

You could try disconnecting the solenoid that controls it and see if the problem disappears. May set a CEL though.

my NB8A does similar, and has so for about 8 years.

I have a wideband in my car (leftover from an old ECU install) and whenever it does that it shows it going a bit lean (about 16:1)

I just use less throttle and it's fine.

yeah when it happens i baby it until it warms up - more so wanted to make sure it wasn't going to do something silly and go bang

Okay, this might be digging up an old post but...

My SE runs like a clock... now.

It didn't always.

My biggest issue, as it turns out, was condensation in the MAP/ BOOST sensor. Took me a while to diagnose, because it was so temperature dependant and basically temperamental.

Take the sensor out and tap it into the palm of your hand, nozzle down. Any moisture, at all, is a good sign the sensor is full of it. Tap out as much as you can.

Leave it somewhere warm and dry for a few days, to dry out.

While you're mucking about in that region... change the solenoid that feeds the sensor too; coz they made of black goat's cheese. (They're sh*t and they don't work for very long, no matter what car they got put into.)

I put a thread on here a while ago, about these issues, check my profile for the link.

Cheers