vibrating and stalling
 

hi, i have an 04 rx8. the car has about 61k miles on it. i was driving to the store yesterday and the car ran fine, when i got back in the car it woul not start back up, i figured it was due to the normal flooding of the engine. i was with my friend at the time so he pushed the car so i could pop-start it. the car started but it was vibrating alot, i waited a little bit and the noise and vibrations stoped, the ride home was fine until i got onto my street where the virations occured again the car stalled when i let off the gas.
I have recently took the car to a body shop to get fixed. when it was there they called and told me that the car wouldnt start(probobly due to the flooding like always). they got it started and i picked it up, the car was running good for about 5 days until this happend. i checked the spark plugs to see if they were fouled up( they were a little) but i also noticed that leading plugs were on the top and trailing were on the bottom, ther saposed to be opposite right? i think the people at the body shop mixed them up wen they tried to start it. so i started it, it ran good for about a minute and then started the violent vibrations agian and eventually stalled. could this problem have been due to the spark plugs being in the wrong spot? or is it somthing else? and responces would be greatly appreciated.

There is an "L" and a "T" on each plug base, which needs to be matched with the big "L" and "T" stamped in metal on the housing next to each plug hole. Reversing the plugs (but not the wires) isn't good, and can cause problems. Reversing the wires, regardless of where the plugs are, can be catastrophic. Get the plugs in the proper spots, along with the wires in the proper order ASAP. Take it to a dealer with the plugs and/or wires wrong and you can kiss any hope of warranty coverage goodbye.

Just in case, when was the last time your coils were changed? They should be changed every 30k, so if they were done right at 30k, you are due for another change. Not getting enough of a charge from the coils to the plugs can cause shuddering, stalling, flooding, not starting, etc...

If replacing your coils and getting your plugs straight doesn't fix anything or return it to normal, take it to a dealer for power loss. Have them do a compression test and/or cat test. And don't mention that the plugs were backwards.

If that ends up being the problem and you get stuck with the bill, the mechanic that put them in wrong is liable, though might be hard to prove.

the coils have not been replaced since i got the car and i will replace them soon.and do you know what kind of problems can the plugs being in the wrong place cause? also when i was runnin messed up i did smell a lot of gas fumes

The difference between the leading and trailing plugs has to do with temperature mainly I believe. The leading plug is igniting a relatively cold charge, where the trailing is expanding the ignition from the leading.

Now, for what exactly can go wrong, I'm not sure, I am not knowledgeable on the specifics. I imagine a harder time for the leading to ignite the charge, and an acceleration of failure for the trailing as it isn't designed to operate in that temperature. Throw in failing coils, and you could have plugs that are struggling to fire at all.

This is assuming the wires are correct and you just have the plugs backwards. Wires being backwards means you have the leading not firing when it should, the trailing fires as the initial ignition of the charge, in the wrong spot on the rotor path, causing the combustion to sweep 'backwards', and the leading plug expanding that ignition in the wrong direction. Seal failure is pretty much imminent at that point.

well i did switch the plugs to ther correct spots and i know the wires are correct as well, i guess the problem didnt really have to do with the plugs being in wrong but i will look into the coils as soon as i can. thanks