help...blocked cat or gearbox?

[jas98]

hi, VS commodore v6 188000 on clock

yesterday hoped in and went for a drive, got to corner (about 1 k up road) and then went to go and felt like it had no power similar to a missfire.


so today i replaced coils and dfi from my mums car as she has a vy commodore but was still the same. then i replaced spark plugs and leads as they are due for it.....still the same. so tried the throttle position sensor still the same.

so basically what its doing is, 1st gear is ok but when it gets into second then third etc and revs up to round 2500rpm its like the brakes are applied and the car just revs very very very slowly to 4000rpm with full throttle and smells like exhaust fumes when you get out of car.

BUT when it finally gets to 90kph and tourq converter locks up revs drop down and it goes like a roket like nothings wrong.

any ideas?

 

[EYY]

Mine was doing something similar when I fitted an aftermaket crank angle sensor. Went to bursons and purchased genuine one and has been all good since

 

[gtrboyy]

Bridge diagnostic pins 5 & 6 above brake pedal? What codes come up?

Give cat convertor a tap see if it rattles..same for the mufflers.
Remove cat convertor & visually check.Other thing I've had is o2 slowly go dodgey car run rougher before any intermittent codes popped up

Possible they could have collapsed over time even if low mileage car + easy & cheap thing to check/rule out.No harm checking but I always check codes first usually to save time.

 

[Not_An_Abba_Fan]

Have you checked the fluid level in the transmission?

 

[jas98]

thanks. the crank angle aensor was replaced with genuine a couole years ago however i have a spare ill try. as i was thinking the same.

also no codes come n up just keeps saying 12 over and over again


seems weired how ince torq converter locks car goes like a roket....as i had foot flat out it got to 120 easy from 90 and still wanted to go like nothings wrong

 

[jas98]

no i thinknof it about 3 months ago the engine light came on but ran perfect. so i checked codes and it said left o2 sensor lean/rich and right o2 sensor lean /rich also a code for bad singnal fornthe left one but i reset computer and all good since

 

[jas98]

Have you checked the fluid level in the transmission?

i did check it and was good. not burnt or anything. but if it was low woulfnt the revs be fine as low fluid it should slip?

 

[Not_An_Abba_Fan]

Not necessarily. It does sound trans related though.

Just had a thought, check the fuel filter.

 

[jas98]

yeah will rip fuel filter off and check. can a failing maf cause it?

just weired how its like the brakes are applied up untill the convertor locks up. maybe a faulty convertor?

theres no wrror codes though.

 

[CCCMikey]

It sounds like a transmission issue to me in that case. What about if you have it in 3rd? The converter locks at 60kph in 3rd if you're not hammering it - RPM will drop to 1500 @60kph, 2000 by the time you get to 80kph