Consistent Misfire

[E46Twist]

Hey guys, I decided it was best to start a new thread now that I have pinned down the problem. From my other post, I replaced the head and timing belt on my 89 325i after the PO broke the belt. after finishing I had trouble starting the car which was a my mistake. Now the car loves to start but will just rev to 1 grand and then die. If I apply a little throttle it will run at about 500-700 rpm and you can hear and feel #2 and #4 missing back to back which is probably why it wont idle since they fire one after another. On inspection I have been able to conclude that I do not get spark from #2 and #4 at the distributor. The cap was replaced with a claimed to be working one and the problem remained although I cannot say for sure it was the same two cylinders on the old cap.

So that really just leaves the rotor as far as I know which is why I am going to ask you guys for input as I do not know the system very well. So again #2 and #4 no spark at dizzy all others are fine.

[jlevie]

First action in this case would be to replace the distributor cap, rotor and wires with new OE/OEM parts and to replace the plugs with NGK ZGR5A plugs.

[DesertBMW]

never heard of this kind of problem. No spark at 2 and 4, I doubt it. You haven't diagnosed the problem. You made a mistake somewhere , didn't install something properly

[E46Twist]

Well we tested each pole 3 times. 2 and 4 never sparked and the rest did. I was using a spark checker, you either see it light up or it doesnt. Yes I could have installed something wring but what would cause that

"Fast is Sexy"

[E46Twist]

Bump

"Fast is Sexy"

[E46Twist]

After doing some more reading is it possible CPS is malfunctioning or the toothed wheel is not on right or whiuld that cause random misfires/no start. I aligned the pin on the crank with the smallest whole in the toothed wheels so I doubt that is it. I am ready to just buy a new motor and start fresh because this is getting more annoying by the day and I see no obvious problems.

"Fast is Sexy"

[jlevie]

A problem with the CPS or it's data can cause problems, but not a consistent misfires or a lack of spark on one or more cylinders. In a like manner the DME and coil can't do this. The only thing that will do this is a problem with the distributor, ignition wires, plugs.

[E46Twist]

Thanks bud