a compression test will tell you a lot but if you've got a lobe / lifter problem you don't want to keep cranking it over thus adding more metal to the motor & oiling system. If you pull the valve cover & all your rockers are tight or within the 10 to 14 thou range then the cams probably OK, THEN run compression.

yes, a compression test will tell you about all these potential causes

is the smoke blue or black, or maybe even water steam . sounds like a possible head gasket.

not a whole lot to go on here but it could be a cam lobe. when they go they go quick & start running crappy & ticking. Check the oil for metal particles, pull the valve cover & see if you've got a sloppy rocker. Now the infamous line - ask me how i know.....

Troubleshoot this exactly as you would an A12. Perform an Engine compression test before you drive it again. If you need help interpreting the results, post them here. Let us know what you find out.

hey guys my 1200 ute with a a15 was running perfect yesterday and last night, i started it up this morning and heaps of smoke came out and is running horrible feels like its running like a tractor and making ticking noises, & drives very lumpy, it had head work done to it about 8 months ago and webber all freshly rebuilt but bottom hasnt been touched, please helpp????