Hi all, my 99 sub.350,300k,missfire #2

SWAP COIL LIKE FROM CYL NUMBER 1 TO 4 AND ROAD TEST UNDER LOADS IF CHANGE THE MISS TO CYL NUMBER 1 NEED A COIL OR BAD PLUG AT CYL NUMBER 4

sounds like the only thing left is the valve lash. If the intake gasket was bad, it would most likely cause a vacuum leak and effect the overall performance of the engine. You may also notice some oil consumption as well. Also, verify the firing order is correct.

Replace spark plug as may be firing inconsistently allowing unburnt feul to buid up and ignite intermitently

COMP.TEST. SPARK IN THAT CYL?

plugged injectors or weak fuel pump
You must wait for someone else to answer the trans problem

You didn't post your engine size so please pick the applicable motor:






Firing order and spark plug wire installation for the 2.5L engine





Firing order and spark plug wire installation for the 2.0L engine

hi from uk i assume you have done all the above work correctly? and the leads from coils are correct firing order 1 3 4 2 ? CAMBELTtiming set correctly etc as you say this has happened since cyl head renewed and miss fire is on Nos 1+2 cyl's this normally suggest now after all work u have done and assume compressions are ok ? i had such a fault on a customers mini some years ago who had done exact type of job as you described this fault turned out to be the inlet manifold gasket had split between cyls inlet ports and resulted in missfire on 2 cyls adjoining on removal of manifold the gasket had been damaged whilst reassembling new gasket cured missfire which had caused weak mixtur on both cyls ie on induction more air being drawn via cracked gasket on each cyl and as your engine if injection same problem?? might be worth checking?? hope this throws some light on the problem?

this car has what is called coil over ignition which means no plug wires or cap so if it is missing swap coil from cyl 2 and any other cyl then clear code and rerun car till light comes back on then check code if it is still cyl 2 missfire then replace that plug if code changes to the cylinder that 2's coil was on then replace that coil <that car does have a recall for coils> if car is not missing and you have that code most likely isnt an ignition problem but will have a small vaccume leak so check the small hoses for leaks. very common for fuel preasure regulater vaccume hose to brake from age

ok since you said you changed the plug and coil pack, start with the injector wire harness and look it over for any shorts or grounds, also make sure the terminals on the no.2 injector connector aren't loose. if you have access to a noid light you can check to make sure the injector is pulsing. check the no.2 plug wire as well. swap it with another wire if you can and see if the miss follows the plug wire. if those fail to solve your problem and the misfire remains on the no.2 cyl, try swapping an injector. if that also fails then you may have a problem with the cyl head.

How is the pressure in the fuel rail? a low pressure will cause erratic firing of the injectors - the further down the rail u get usually the worse the problem. If the fuel filter was not changed regularly or if the vehicle stood for a while, dirty fuel/standing fuel at some time in the recent past, this **** will accumulate in tyhe injectors. To avoid spending a loada cash, swap a few injectors around and see if the problem moves with the injector.