[Z06] Dead 04 Z06
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2nd Gear
Joined: Nov 2007
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Dead 04 Z06
I have an 04 Z that began missing and backfiring about a couple weeks ago and has progressively gotten worse and now all it does is turn over without firing.
The issues started after the engine got wet by someone not being careful with the hose while I had the hood open (long story). At first it would just miss every so often, then it started backfiring a couple days later. On the fourth day it started acting like it was getting flooded and would chug and backfire for a couple minutes then work itself out of it or die and then would start right back up. I decided to replace the plugs and wires as a quick first step and it seemed to run better for a few hours. Last Saturday it was running so bad it wouldn't make it out of the driveway and Sunday morning I went out and tried it and all it would do is turn over and not fire at all, this is where it is at right now. The odd thing you can smell gas like it is flooded.
The other odd thing is it never threw a code until Sunday when it wouldn't start. When I bring up the codes on the cluster I am showing these; P0120, P0220, and P1516. The sheet I downloaded doesn't show the first two so not sure what they are.
I am uploading a few videos I took of it where you can hear it backfire and then die and then another one that was the last time it actually ran. Hopefully these videos work, if they don't let me know and I will post them somewhere besides youtube.
Video 1. you can hear it backfire around 28 seconds
Video 2. Starts hard, backfires at around 18 seconds and then dies
Video 3. This is the last time it has ran.
Any ideas on what to check and/or try would be appreciated.
The issues started after the engine got wet by someone not being careful with the hose while I had the hood open (long story). At first it would just miss every so often, then it started backfiring a couple days later. On the fourth day it started acting like it was getting flooded and would chug and backfire for a couple minutes then work itself out of it or die and then would start right back up. I decided to replace the plugs and wires as a quick first step and it seemed to run better for a few hours. Last Saturday it was running so bad it wouldn't make it out of the driveway and Sunday morning I went out and tried it and all it would do is turn over and not fire at all, this is where it is at right now. The odd thing you can smell gas like it is flooded.
The other odd thing is it never threw a code until Sunday when it wouldn't start. When I bring up the codes on the cluster I am showing these; P0120, P0220, and P1516. The sheet I downloaded doesn't show the first two so not sure what they are.
I am uploading a few videos I took of it where you can hear it backfire and then die and then another one that was the last time it actually ran. Hopefully these videos work, if they don't let me know and I will post them somewhere besides youtube.
Video 1. you can hear it backfire around 28 seconds
Video 2. Starts hard, backfires at around 18 seconds and then dies
Video 3. This is the last time it has ran.
Any ideas on what to check and/or try would be appreciated.
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2020 Corvette of the Year Finalist (performance mods)
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p0120 and p0220 are tps circuit malfunction codes... if it ran fine before the motor got wet I would unplug the connectors from the throttle body and examine the pins and wiring... make sure everything is dry, make sure the pins are tight and getting a good connection, check for corrosion, and take a look at the condition of the wires going into the connector
Last edited by StingrayRebel; Aug 18, 2015 at 05:26 AM.
Safety Car
Joined: Jan 2006
Posts: 3,940
Likes: 42
From: shavertown Pa.
I had a c4 that started getting weird after washing the engine, it turned out to be water inside the main plug in, going into the optispark.
Your system is different, but it does depend on sensors to know when to fire, I would start by pulling each sensors plug then blow them out.
On mine the plug in question faced upwards, it allowed it to hold water, what happened is the water expanded when hot then shorted out the prongs.
I hope your problem is as easy fix as mine was
Your system is different, but it does depend on sensors to know when to fire, I would start by pulling each sensors plug then blow them out.
On mine the plug in question faced upwards, it allowed it to hold water, what happened is the water expanded when hot then shorted out the prongs.
I hope your problem is as easy fix as mine was
