slowjoe99

iTrader: (7)

I know... long write but I NEED some help please!

One day it had been raining out and I took my car to go to the bank which is only about a mile from where I live. As soon as I pulled into the parking lot and got into line at the drive through i noticed the car was idling rough, and at about 100 rpm's lower at 500 instead of 600 rpm's. My service engine light was on but always is cause of headers and no rear o2 sensors and I removed me EGR pump. when I took off the car had NO power! after a while the problem just went away and nothing happened for about another month when I took it to an automatic car wash. It was the kind that sprayed up from underneath when you drove in. As soon as that happened my car started idling rough again, and shaking the whole car. so I shut it off. when it was time to leave the car wash the problem was still there. when I took off the car had NO power again. I seen the tac say it was at around 25 to 3k rpm's but i didn't sound like it when taking off. soon after the service engine lights started flashing! I knew that meant something serious was wrong so i pulled over and shut it off. after a while i started it back up and the SES light wasn't flashing anymore but was still running funny. I drove over to AutoZone that was close by and got the codes read. there were 10 codes! 8 or 9 were for the o2 sensors and EGR and one was pending and said "Random Multiple Cylinder Misfire". after a while i started it back up and it drove fine, the power was back and it was idling good. I thought it may be something with the transmission trying to take off in second or something so I tried manually shifting it but it didn't seem to help. anyone know what could be wrong?? please help if you can!

Magna5.7

my gues is loose wires to the 02 sensor or maybe the 02 sensors are failing. This might have put your ecu in limp home mode.

IROC403

iTrader: (2)

check the ecm plugs, i've seen a few leak water into the connection.
its right below the windshield where all the water runs down

ae13291

iTrader: (8)

my cars check engine light came on for the o2 sensor and because of the o2 sensor it threw a multiple misfire code and the check engine light flashing. but my car never entered limp mode lik u said! but i would check on the o2 sensors i replaced my bank 1 sensor 1 and everything was fine after that

sixvi6-camaro

iTrader: (9)

bad/cracked porcelain on a plug, bad wires, could be anything ignition related as it would be sensitive to moisture but a bad O2 could for sure cause it especially from the codes it is throwing.

araber89

iTrader: (3)

We had a similar problem on our Dodge. It ran like a banshy on crack until it was warmed up. The mechanic took it in and and sprayed a mist of water over it. When it hit the plug wires it would do what you said. He said the water was shorting out the wires and the plug wasn't firing. This could cause your "Random Multiple Cylinder Misfire." If I were you I would change your plugs and wires good ones are worth it anyhow. It sounds like once your motors warm it drives the wires and they don't short out any more.

HDNVALLEY

The random multiple cylinder misfire was likely caused by plugs and/or wires. I'd replace them and be sure to coat the connections on the new ones with dielectric grease to prevent water from shorting them out.

ms4z28

hey my car did that it might be the same as what happen with me check out the crankshaft position sensor

RE AND CHERYL

iTrader: (31)

What you describe is EXACTLY how my car ran after water got into the ECM plugs when I washed it. Disconnect the ECM plugs (after you disconnect the battery), I'll bet one or more of them has water in them.

Re'