Cold & Wet Misfire?

Errant

Errant

Well-known member
Oct 1, 2004
767
20
Southern California
Hi all :)

After some rain and sleet last night, my DI started fine but ran really rough and had no power. After about 10 minutes of warming up, everything was back to normal, no warning lights on the dash.

Time for new plugs and wires? Is there anything else you think I should check?
 
Errant

Errant

Well-known member
Oct 1, 2004
767
20
Southern California
But, Chris, Summit shows two different plugs that are supposed to work CPN-4318 and CPN-318. And then I read in another post that they should be RN11YCC. I'm so confused :eek:
 
Errant

Errant

Well-known member
Oct 1, 2004
767
20
Southern California
An update: Changed plugs and wires (Magnecor 8mm and Champs). All was well until this morning, after the snow. Same deal, starts fine, misfire as soon as you give it any gas, better once it warms up.

What should I look at now?
 
Errant

Errant

Well-known member
Oct 1, 2004
767
20
Southern California
Yeah? So how do I check that?

I'm not so sure that's it, though, I think it's something getting wet because it happened once before after stomping through a big puddle (just remembered that!)
 
J

jhelton001

Well-known member
Jul 20, 2005
106
0
I bet you crank sensor wires have cracked from the heat of the exhaust manifold. When the sensor wires get wet the water shorts them together just enough to have ECU go crazy. Symptoms are no power, backfire out the intake as you give it gas, and the best part is idle is almost normal. As it drys out it goes back to normal and all will be fine till it gets wet again.
I know this can happen as I chased this problem for a year was stuck on the side of the road 3 times in the rain and did all above and nothing helped till I found this problem. The best part is that after I resealed sensor wires I have been in many heavy storms and flooded roads and have not had a problem.
 
J

jhelton001

Well-known member
Jul 20, 2005
106
0
The wires are in a black 1/4'' loom running up and down on the driver side. The sensor is at the rear of the block just before the trans below the exhaust manifold. You can see wires if you look through the driver side wheel well. I wish I had a picture but....On mine the wires were cracked at the plug for the sensor so follow the wires to the sensor and you should be able to feel your way there.
 
Last edited:
R

Randall

Guest
Crank Shaft Sensor Replacement

The Crank Shaft sensor is located under the trunk on the driver's side of the flywheel housing. It is difficult to see because the sensor is covered. The wires to the sensor are routed between the driver's side valve cover and the firewall. Follow the wires down to the sensor's cover and remove the cover with a 1/4" deep well 7mm socket. This bolt is long and a PIA to get out/in. Once the cover has been removed, unplug the connector and remove the second 7mm bolt to remove the sensor. Pull the wires up to the engine bay to inspect and/or repair and clean/replace the sensor. Installation is the reverse of removal :cool:

I am sorry if these instructions are incomplete or poorly written, but I am in a hurry and wanted to help out a fellow Disco Owner...Good Luck
 
Errant

Errant

Well-known member
Oct 1, 2004
767
20
Southern California
OMG, how did you guys get that f'ing shield and sensor out of there?? I have long, skinny, girlie arms and hands and I still can't do it. Seems like the only way is to drop the exhaust :(

At least now I know that the CKP sensor is definitely the problem. The wires look thrashed. I just have to figure out how to unhook it so I can replace them!
 
You must log in or register to reply here.
Top Bottom