Power Drop after hard run.

[SIKCVC]

I really need some ideas for a troubleshooting list for which could be causing this problem that I can just tick off.

After a bit of freeway driving getting the engine temp up, I went for a hill cruise, nothing too heavy. Pushed into VTEC a few times and the engine was running 100%! I slowed up through a short built up area, then once in the clear opened it up to 7000-8000 to reach the 80km speed limit, I think quickly went through the gears into 5th to climb a decent sized hill but nothing too much for 5th @80km. and the engine was laggy as all buggery, NEEDED 4th just to get up it.

Then the problem went away engine ran fine again. Gave it a bit of a push to try and get it to screw up again, sure enough it did, this time it would struggle to accell from 70-100 in 5th on flat road.

On my way home, i tried reseting the problem by switching the engine off... and it worked for a short time. I tried it a second time at a set of lights, when i went to start it, The engine check light stayed on and the fuel pump wouldn't switch on to prime the engine. I tryed a couple more times and the light went out and the pump primed.

This is 100% an electronic problem because the car runs so perfectly then just cuts into a sort of limp mode, but no ECU check light which i dont understand!

It used to have a hunting/idle problem but I have fixed that and now its just this total lack of power after fairly hot running.

ANY ideas would Be GREAT!

Thanks in advance

Nick

[ECU-MAN]

what are your leads like

[VT3C]

On my way home, i tried reseting the problem by switching the engine off... and it worked for a short time. I tried it a second time at a set of lights, when i went to start it, The engine check light stayed on and the fuel pump wouldn't switch on to prime the engine. I tryed a couple more times and the light went out and the pump primed.

This happens sometimes if you turn off the ignition then back on too fast.. it kinda startles the system and it spit's the dummy.. as you found out, just give it a minute and she'll be OK..

as for your drop in power, when you comming DOWN hill, yout thottle is shut thus not letting in much cool air, therefore the intake manifold and TB will soak up a LOT of heat from the Motor that usually is dispersed by the constant flow of cool intake air through an open throttle.

a HOT intake manifold and intake can drastically effect the 'power' of your engine, and if the intake air is hot, the motor will run leaner which can be less 'power' again..

now as ECU man has correclty asked about your leads.. well a tired ignition system, over advanced timing, or even retarded timing, fouled plugs or work leads can also cause a drop in power. add heat into the equasion from some hill driving, and you end up with big drops in power.

[SIKCVC]

Ok, please read my example of what had happened. It was running fine for ages, then I opened it up and it took it fine, then it cracked it. It cracks it after hard running. I let it settle and then it was fine, i ran it hard and it cracked it again.

At the lights I let it sit for about 3 mins before i tried to restart it and THEN it screwed up. It wasn't a quick on off type thing, I've seen quick on off type things, the engine can even tick over on compression and start up if you're quick enough.

The timing has been checked
The leads are good (cant be leads anyway because its an intermitant problem)

Its not a heat thing because I'm not talking 10kwts I'm talking 30%+ power loss. at LEAST 30-40kwts.
Its like driving a Gli civic when it craps out on me.

My thoughts have been
Fuel pump, either surging or failing.
Screwed up sensor (hasn't been found by BLKCRX or wardwhile motors because they havn;t replicated the problem)
Injector problems.

[SIKCVC]

thanks for the ideas though guys, hope what I added will illiminate things.

[SIKCVC]

Need help fairly bad guys... any ideas?

[panda[cRx]]

i had kinda similar things before and it turned out to be dizzy problems.

the car would driving fine until i gave it a good revving then the power would die down and sometimes stall

[SIKCVC]

might be worth checking out... what was the actual problem? because physicly the dizzy cap looks fine.

[wlee2]

get someone to look it over. stock civic ? sorry i dunno what car u run =P..

i never really except many cars to accelerate fast in 5th gear =P..

[SIKCVC]

Its a stock SiR with Intake and Exhaust mods.

Its not a matter of it just not acceling fast... its a total power loss of around 30-40kwts.

I've had a few top mechanics check it over and cant find the problem because it cant be replicated without driving for some time.

[wlee2]

well i dunno if you havent already tried but umm u talked to pornstar yet ? or have it looked over by him?

[SIKCVC]

I've had it checked out by James (BLKCRX), Wardwhile motors and ART.