Engine is rough under load, okay when no load
Hi,
The subject basically says it.
Last week I played around with the vacuum actuator assembly, which in the end I rebuilt, that seems to work okay, so I took the car to the shops, no problems at all, did the shopping, backed the car out, and went home, immediately felt the car had no power and basically on hills where 4th gear was fine I was down to 2nd gear to make it.
So, thinking I had caused the problem, I removed the vacuum line to the vacuum solenoids for the free wheel clutch, made sure it was air tight, same problem, so I guess it has nothing to do with that.
Replaced the spark plugs.
Next, checked I had spark on 3 of the cylinders, a bit hard on number 4, but decided after some playing that it was working.
Did a compression test:
1. 171, 2. 181, 3. 170, 4. 178, which looked close enough together, with 293Mm on the odometer.
The leads are petty new, but I suppose they are the next obvious choice.
It's a 4g94 motor.
Any thoughts?
Thanks.
Ian.
Rough under load
Hi Claude,
Looks like I have traced it to a coil pack, when it has an easy path to earth the spark comes out the end where the spark plug goes, if you make the path harder the spark starts coming out at the top of the shaft(?) near the actual coil, so the insulation has failed.
Hand brake "on" :)
That would be the wife in control
Ian.
Is this a GDI engine?
I've had a couple of the coil packs on my GDI engine fail - burning through the plastic of the actual coil pack where the rubber boot attaches - and arcing across to the cam cover. They can sometimes be fixed by carefully drilling out the hole to remove the charred (conductive) plastic and then filling it in with RTV silicone. Of the two that failed and were repaired, one failed again within an hour or so, and the other works reasonably well - I get the occasional missfire at cruising speed (I don't know if it misses under load, but I have not felt it), I keep this one in the back as a "get me home" spare, along with a 10mm nutdriver.
If it's the rubber boot, those are supposedly available separately.
Not GDI
Hi Fordem,
It's not a GDI motor, but that seems to be what it's doing.
I was going to buy another one tomorrow, or more probably the next day as I need wheels to get anywhere, nothing is open here on Sunday, to replace it.
I was also going to try and "fix" the broken one and have it as a "just in case" spare as you have done, assuming I can "fix" it.
Ian.
Coil pack
Hi Claude,
I only bought one, which was $35.
I tried to repair the old one, while I have made it stop arching over to the rocker cover, it still doesn't work, so it's the bin for it.
I am thinking of buying a spare off ebay, as I'm going on holidays in about 2 weeks, hence all the TLC I have been giving the car lately.
Ian.
Syndicate
no power
Even though you have a spark at the plug doesn't mean that they are working under load. Coil pack, lead could be faulty. As soon as the engine work a bit more (under load) if the spark is weak, it will fail and loose power. That will be my first guess, usually the engine will be missing as well. Were the old spark plug the same colour ? or one/two was darker black ?
Fuel filter could be another cause, or even a dirty air filter ( very unlikely as it will have to be very very bad to do that !!)
Hand brake "on" :)
Happy io
My io is now SOLD Thankshttp://pajerio.com/forum/claudes-io-2002-zr-built-thread-onlyhappy-io