please help

[nazz]

hi all
some times when i start my 4.7 WH it runs real rough and when i put it into drive and accelerate i have no power what so ever for about 20 secs after that everything runs normal has anyone come accross this problem or does anyone know what the problem is?
thanks

[briteway]

Could be one of the sensors. I'd suggest to replace the pre cat O2 sensors and your Crankshaft Position Sensor and while you're at it, replace the PCV valve and the MAP sensor and your air filter. With the O2 sensors, make sure they're NTK otherwise, other brands will give you issues.

You can get all these parts from the US at a fraction of an Oz price and at your doorstep 4 days after purchase. Check rockauto.com.

There's plenty of info on how to replace these, but if you have any issues post here and we'll help especially with the new MAP sensors I couldn't find any info and ended up "customising it."

[turbomart]

Sounds a bit like dribbling injector but bit hard with such limited info.
Did you try checking fault codes?

[redneckjeeper]

Worst case cenerio, head gasket problem leaking water into cylinders overnight, is it loosing coolant ??

[Doctor W]

Originally Posted by briteway

Could be one of the sensors. I'd suggest to replace the pre cat O2 sensors and your Crankshaft Position Sensor and while you're at it, replace the PCV valve and the MAP sensor and your air filter. ."

A bit of an expensive way to go about it........best to check what is actually wrong before throwing in a lot of new parts on the off chance you might get lucky and fix the problem!

[nazz]

Originally Posted by redneckjeeper

Worst case cenerio, head gasket problem leaking water into cylinders overnight, is it loosing coolant ??

no not losing any coolant this only happens every now and then id rule head gasket out im guessing its air related i havent checked error faults coz i dunno how to

[briteway]

Originally Posted by Doctor W

A bit of an expensive way to go about it......

Not really. If the parts turn out to be OK, then save them for future use, they will end up needing to be replaced eventually.

Sensors are around $30 each, standard air filter around $10.

Most of the time, when the engine starts playing up like that, it's electrical issues and in that case, most of the time it's the CPS or the O2 sensors.

Better than getting the dealership to "guess" where the problem might be and for every wrong guess they suck the $$$ out of your wallet. They were going to charge me $165 for O2 sensors, part only. LOL, they're expensive.