I'm having issues again with the car, not sure what it is this time - hopefully someone will be able to enlighten me!

My car has seem to lost a lot of power. It no longer has the acceleration it used to. The first indication of this came when I changed the oil, oil filter, and spark plugs a few weeks back. The car randomly lost A LOT of power, so much so that I could only get up to around 50mph and any hill defeated me (full power seemed to return, though). I thought maybe it was the spark plugs (NGK V-powers), so I re-gapped and retorqued em (25-30Nm). That somewhat solved the problem, as I no longer randomly lost a lot of power, rather I lost some power all the time - not exactly an acceptable solution. I tried resetting the ECU, no help (no CEL either). So today I change out the plugs again, this time with the same kind of plugs I had (new Denso Iridiums). Problem remains unchanged.

The best "test" I've come up with that may indicate what is wrong - the car will not rev past 5.2krpm or so, even when coasting in neutral. I press the throttle and at about that RPM, the engine seems to struggle as if it simply doesn't have the power to accelerate even just the crankshaft any faster.

I've kept up with maintenance pretty well, oil changes, spark plugs, wires, filters, etc. I even got a new shortblock about 10kmiles ago. So, suggestions on what is wrong with my car are appreciated fing02.gif

 

Air filter plugged? Wish i could help more...

 

Does it idle rough at all?

The no CEL thing is pretty strange...

If the MAF were dead, it would throw a code. If the cat got blown, it would throw a code. Only thing else I can maybe think is air filter is fudged, or you have vacuum leaks somewhere. Your fuel injectors could be doing bad as well possibly. I don't know anything about coilpacks, that might be a possibility.

 

check and replace you plug wires.. and are you CERTAIN you are using the correct plugs?

 

I'm still curious, if its spark related, why it doesn't throw a misfire code. Especially since the problem is so pronounced.

 

i'm thinkin either your wires are cracked or no good or maybe a faulty coil pack.

well... it happened after u changed oil and plugs. oil will not change the power of your car cuz its a lubricant. your plugs will and even though u have changed the plugs u had to move the wires to do so and that means u altered the way your car was so everything u altered/moved/changed CHECK !

also check your tps while your at it

u will find the problem fing02.gif

 

I replaced my spark plug wires about 20kmiles ago with NGK wires. They still look pretty good to me, no signs of wear. I've never heard of our coilpacks going bad, but I can check the resistances of those tomorrow and report back - I'll test the wires too while I'm at it. Also, I'm quite certain the spark plugs are the right ones - I've tried two sets of plugs and both did the same thing, so... ? Idle is fine, and other than lost acceleration everything else seems normal. Thanks for the replies.

 

Your problem is an odd one indeed.

Whats the mileage by the way?

 

give us some more info on this loss of power. does the car shake any? does it sound different? lights dim? fire from under the hood? anything?

 

Could it be anything to do with your fuel filter being clogged-up?

My car loses heaps of power when the air-con is on too wink1.gif