Lumpy Idle and Lack of power

mic* · 19-01-2006, 12:09 PM

Firstly i would run the thing and try pulling off the ISCV and TPS one at a time. Both should affect idle. If nothing happens test it more thouroughly. I am more sus on ISCV, particularily if (as per Takai) it uses wax pellet thing - i am not familliar with this but have heard about it being inconsistent.

If you restict the inlet, it should run a bit rich. This should either bring the idle up a bit or make it die altogether coz your plugs are the problem (gap or sealing cylinder properly)

**EldarO** · 27-01-2006, 07:35 PM

Originally Posted by urantia

could be low compression on 1 or more cylinders as mentioned above, well it could be. Altho you say it idles fine on first startup, and then gets shit.

I have a 3sge that misfires and runs really rouph until it warms up and comes good again,
I buahgt the engine not long ago, it had new spark plugs, new dissy cap and leads. Seemed like the previous owner figured the misfier/rouph running was spark related.

Didn't take me long to relize that the compression was low on cylinder 1. I got an air compressor into the spark plug whole on the low compression cylinder and closed the valves and listed where air was leaking from, wasn't leaking out the exuast or the air intake so that narrowed the valves out of it, pulled the dipstick and i could hear air pissing out thru there, so most likely rings are the prob in my case (or headgasket).

So once the metal expands it must be able to regain some compression and fire the fuel mixture properly.

So a comp test would be something to check out for sure.

Would this be the meanie known as Blow-by?

Maybe check if the dipstick keeps getting blown out, by a little bit, of its holder?

Eldar.O.

**pomey** · 27-01-2006, 07:58 PM

No experience with this problem or motor, and it may have mentioned in some other form but has automatic choke beem considered, assuming they're on this motor.

Sorry for my ignorance but just tryin to help and maybe learn a thing or two.

Cheers, Pomey!

**takai** · 27-01-2006, 08:18 PM

Originally Posted by pomey

No experience with this problem or motor, and it may have mentioned in some other form but has automatic choke beem considered, assuming they're on this motor.

Sorry for my ignorance but just tryin to help and maybe learn a thing or two.

Cheers, Pomey!

That woudl be the ISCV.

Originally Posted by EldarO

Stuff about blowby

Blowby is where compression gasses find their way past the rings and pressurise the crank case. Normally this is mainly manifested by having lots of oil coming out of the PCV. But occasionally it can pop the dipstick. Only very occasionnally.

**urantia** · 27-01-2006, 09:07 PM

eldar O, You'll find just about all 3s engines have abit of blowby. And with the gen1 don't actually have a pcv valve, but a fixed orifice for reburning oil vapours/oil, blowby.

Even noticed very low Km beams motors red top and black top have quite abit of pulsating air coming from the oil cap.

**mrshin** · 28-01-2006, 12:32 AM

Pomey, it's been a fair old while since cars have had a choke. Thankfully...

**4DaDrift** · 28-01-2006, 02:39 AM

Edited post.

**AJz** · 02-02-2006, 07:08 PM

yes, believe me i have checked quite alot of things.

**JetspeedCamry** · 02-02-2006, 08:47 PM

This sounds very close to the problem i have with mine. Sometimes the power just isn't the same, and the idle acts up. It drops to 500 or so then bounce up to 700 and back down again etc etc till it equalises out.