I was driving and 5 miles from my destination I lost a cyl. Pulled over and I think its the coil on number 4 because pulling the plug for it has no effect, the others bog the engine even more. Disconnecting inj 4 shows a change in the AFR's, I am guessing cause its just igniting the gas in the exhaust.

Would it be safe to drive home 46 miles on 3 cylinders?

Should I disconnect the injector on number 4?

 

the extra fuel would dilute the engine oil and destroy your CAT. and it would seriously wash down the cylinder and do some damage to the wall. hmmm......without the injector connected it may be alright, though i don't have any personal experience trying such things.

 

I wouldn't do it for the above mentioned reasons. Have someone tow ya, or swap coil packs, etc.

 

What about disconnecting the Injector?

If I do that, the above reasons no longer come into effect.

 

It's not a good idea. You'll run that cylinder cold. It will wear more. Granted there are engines that cut off cylinders, but... if you disconect the injector it would probably work. The O2 sensor will be seeing a lot of O2, so I hope EGO is off.

 

Sam, are you sure it's not the spark plug?

 

If you disconnect the injector wires, you should be fine. It wil not hurt having that piston a little cooler. It will oil just the same and will actually be less tight in the cylinder bore due to a lack of the normal thermal expansion. You should be fine. I drove home on two cylinders before (long story). You should be fine.

But definately pull the plug on that injector so you don't damage the cylinder wall and other things due to washdown and dilution of the oil.

 

If there is no failure in the rotating assembly, I don't see how there could be any new damage would be done if you disconnect the injector and plug wire. Wouldn't be any different than cylinder shut down used by nearly every recent v6-v12.

 

i attempted this on an eclipse once, for some reason that i never understood the damn thing ran really hot

 

Didnt want to risk it, left the car overnight and picked it up this morning.

It was the coil. Swapped in another and was on my way. While driving I decided to get into boost, all of the sudden the car jerked. I stopped checked everything, now the car refuses to go over 6psi into boost. Thought it was the boost controller but it was not.

Then I went to my friends house and lost another coil after the car sat for 4 hours. Went to start it and its running on 3 cyl, this time number 1 died. Luckily I had another. Driving home the car just fails to go over 6psi of boost, and when it does the megasquirt resets spontaneously.

Now I am home with my coil harness on my table and im contemplating just sticking my factory coils back in.

This is bullshit from day one with coils for me, and even a second set acts the same god damn way.

If im not running 6ms dwell, the car refuses to run.

 

If you are getting MS resets I would strongly suggest checking your grounds. It could be a grounding issue that is causing all your problems.

 

Ill take a look, but nothing has changed for a year since I started running the megasquirt.

Heres a dumb question.

I have two caps of 4700uf, should my DMM read 9.4 M Ohm? Cause im only getting 2.1 M Ohm.

 

yea, that question is dumb...

 

Yea, dont drink and post on miata turbo. 100 proof scotch is strong ****.
Just realized im measuring two different things.