ALFAGTV6.COM

[x-rad]

New problem while out driving:

Less power when starting off and feels like I am running on 5-5.5 cylinders and then (at 2500-3500rpm)...a normal feeling surge of power till redline. Idle is also a little higher (200 rpm)at times...I figure its an injector problem so I ordered some newer ones.

In the mean time , I checked wiring connections all appear OK.

Have original spark wires(probably should replace)

New plugs rotor and cap already in.

Anybody with similar experience??

[x-rad]

C'mon now...nobody had this problem????

[Zamani]

I had the exact same symptom as yours and it turned out to be problem with tight valve clearance. But tight valve clearance doesn't happen overnight.

[MR2 Zig]

A vacum leak might show overnight and would cause the idle speed change.

maybe an injector seal???

let us know what you find.

scott

[Mats]

I'd have to guess air leak too. Check all hoses, don't just look at them, bend them around and such.

[x-rad]

Thanks..will check...

[x-rad]

Today:
put in new spark wires, new plugs, checked ALL hoses and diaphrams for leaks, fuel pressure OK, changed air flow meter, checked wiring, changed TPS,new fuel filter (did not check the hoses on top of the fuel tank..)


still have intermittent decreased power which picks up under 3/4 throttle back to normal, no knocks, no backfires...

only thing left are the injectors and valves(but compression is fine).
Can you have a 'sticky' injector or are they always just on or off??

[Mats]

Which enigne is this?

[x-rad]

3.0L 12v

[Barry]

New problem while out driving:

Less power when starting off and feels like I am running on 5-5.5 cylinders and then (at 2500-3500rpm)...a normal feeling surge of power till redline. Idle is also a little higher (200 rpm)at times...I figure its an injector problem so I ordered some newer ones.

In the mean time , I checked wiring connections all appear OK.

Have original spark wires(probably should replace)

New plugs rotor and cap already in.

Anybody with similar experience??

X,I replied to this but saw that you had already fitted a new cap and rotor..

Now what make cap an rotor have you fitted??
Ive used only Bosch for years..Tried Echlin but they are not good quality for our cars..on other makes they are superb..(covering my ass here..)
Put brand new stuff in,dont clean or try sanding anything here..I still feel its cap and rotor related.Is the rotor firing head on or from the side ?
Have you checked that looong lead from the coil to the cap as well??

My money is on these items here..

[x-rad]

brand new Bosch (yellow box, red letters) and changed coil lead...checked plugs and the burn pattern looks very normal

Problem remains the same ....feels like running in five cylinders (intermittently) until about 3500 rpm..then runs like normal

Interestingly, after a hard run yesterday, i turned the engine off for about 1 hour...then started it again...problem was GONE the whole ride home!!!

Problem back this AM...feels like when you first start FI engine that has been sitting for a while

idle back to normal, too....

[Barry]

Steeeerange!!!Check coil output(spark)Is it dull yellow or a nice angry blue spark..If its yellow,its weak..Have you tried the coil yet!

Love the yellow box red letters...

[MR2 Zig]

X,

have you changed the injector seals recently? I'm still leaning towards an air leak. Try (with the engine idleing poorly) adjusting the idle speed down in the normal fashion. If you can adjust it then you have an air leak, if not then its spark related.

just thought....to check like above but instead of messing around with the idle adjuster itself pull off the air hose that goes to the adjuster, plug the intake hose end (thumb works here), and use your other thumb to vary the air going to the idle adjuster.

Also try pluging off your aux air valve.

HTH,
Scott

[Sporttunergtv6]

is it possible that your spark timing is a little off?

[x-rad]

all six inj seal new...will check above

Timing is correct and advances fine, problem is low rpms