is there any difference between a 318i engine and the 318is?

[MG325i]

for the most part its all the same isnt it?

[Adrian_Visser]

There was an early 318i (84-85) and a late model 318i made in '91. The 318is was only '91. Both late models had m42's which were the same, the only difference between a late model 318i and 318is is the 'is' suspension, LSD diff. and subtle aero package with front lip and spoiler. Obviously an early model with the m10 is a different engine.

[Danny]

The m42s are the same between the models.

[MG325i]

okay cool. just making sure. i swapped the m42 318i motor into my IS that im working on. ran fine before i swapped it into the other chassis. but now theres a ping if i give it throttle. as if the spark plug is igniting to early before the piston reaches the top... im kinda stumped since these motors dont have a distributor...

[Danny]

Did you do any work to the timing chain? How old is the motor? What about spark plugs? 91 octane?

[MG325i]

no work on the chain. i bought a 91 318i parts car that got rear ended. the place i bought it from told me the motor had been rebuilt. i drove it around before i did the swap and it ran smoothly. after swapping it, now theres the ping. maybe i made a connection wrong? btw, ill have to take a picture of it, but i have an extra part that my dad and i cant figure out where it goes. maybe you might know danny. ill get a picture of it tomorrow and send it to you.

[Danny]

Are all the coil packs firing? All your spark plug wires plugged in tight?