engine cuts out at 4500

[blysccr]

i just got a 91 318i. i paid an arm and a leg for it. 2 days and 200 dollars later it's mine. while driving it home, i was getting on it to compare to my 325ix. i'm pretty sure it will run circles around it. but it cut out at 4500 rpm. it was like it hit a rev limiter at this speed. any ideas as to why this would happen? i replaced valve cover gasket and spark plugs. the intake boot has bad bad tears, so i put another one on but the vacuum line fitting was wrong size, started it up, and still cut out. also, it runs like shit now. if i'm standing on the passenger side of the vehicle, and i'm going to call the cyclinder closest to the cabin number one, number 4 would be furthest out, what is the spark plug order? thanks

[Jak318]

Get your vacuum leaks fixed first. After that it sounds like it could be coils or plug wires. When matching the plug wires up just go 1 through 4. Number ONE being the front most cylinder. The coil pack should have numbers on it.

Do you know anyone else with an M42. You could swap parts.

Could also be fuel related.

[beegeezy]

If your engine runs, and goes to 4500rpm, the sparkplug wires are most likely not crossed. If you just want to take the plugs off, look at them first, theyre numbered. Makes it easy peasy to reinstall them.

[blysccr]

when i first got the car it ran fine till 4500. then i took out plugs and plug wires to replace valve cover gasket. i put them back on and it still cut out at 45oo. so i took plugs out, inspected them (they were new) and then it never ran good, it rumbled like a high lobe camed v-8

[Cobra Jet]

When was the last time the fuel filter was changed? Have you checked for any stored codes? Check all of your vacuum lines. Make sure the plug wires are pressed down and secured onto the plugs and coil packs.