CosmoRx

Hey guys, Last night I went for a real spirited drive, everything was beautiful. Gave it a 2 minute cool down, was good. Went out this morning to start the car and it barely would start, was idling real rough with no vacuum and ran like absolute crap/slugish as hell. First thought was wow my motor let go so before I went off the deepend I pulled it on the rack pulled plugs and I was all fouled out. Ran a compression test and everything looked good, put new plugs in and now the car starts normal but still idles rough with still real low vacuum, barely moves. The guys think I got a bad coil or something, what does it sound like to you guys? It seems almost like a rotor isnt firing. Is there a way to test them if that sounds about right. Coils got 10x,xxx miles on em.

CosmoRx

Forgot to add, when I rev it out good bit of black smoke.

Seventh Heaven

iTrader: (1)

I would suggest checking the MAP sensor hose to make sure that it hasn't popped off. If the vacuum hose is disconnected it will cause the car to run rich.

Seventh Heaven

iTrader: (1)

In case you don't know where the sensor is:



The vacuum line goes from the MAP sensor to a nipple on the UIM right after the throttle body. Also there is supposed to be a small filter in between, to protect the MAP sensor.

jkstill

iTrader: (11)

I will second that. It happened to me shortly after I got my FD, oh so many years ago now.

There seems to have been quite a few incidences of this appearing on the forum of late. Could be a lot of original hoses that have just lost their elasticity, and pop off easily.

jeff p

Hey Seventh Heaven bet you couldn't wait to show off that clean engine bay LOL.. looks nice!

Jeff

Dudemaaanownsanrx7

iTrader: (23)

map sensor or its only running on one rotor. check the easy one first. then check for spark on all 4 wires using a spare spark plug. If you have spark check that the injectors are working

Seventh Heaven

iTrader: (1)

It is quite nice, but unfortunately it's not mine....

I just grabbed that from another thread. I believe it's C's-7's car.

Jarsky

i had the same problem, turned out i somehow snapped the head off one of the spark plugs so I was only running 1 rotor housing.

mono4lamar

iTrader: (32)

Get a simple ignition tester. They sell them at autozone for 10 bucks. It plugs right in where your spark plug would then you clip the other end to a good ground. Crank it over with the fuel pump disabled and check each coil. My other guess would be that it's injector related... Good luck

Dudemaaanownsanrx7

iTrader: (23)

^^
You can do the same thing with just a spare spark plug and ground the plug against something.

Farkel Jr.

iTrader: (10)

Hopefully it's just your MAP sensor line like people are saying, I had this problem a couple weeks ago. I thought the worst, but turns out I knocked off the little line connecting to the sensor on the firewall when taking off the elbow. Stuck it back on, drove the car for a few minutes, and everything was back to normal good luck

mono4lamar

iTrader: (32)

Yes you can do it your way. That just shows spark, not strength. The tool I'm talking of you can adjust the gap to show strength, plus its much easier to see and use than just grounding out to the block. It all works though