Another P0420 and P0300 error thread =-|
2000 SE (I appologize for the length of this thread)
I have read pretty much all the posts here in this forum about the P0420 and P0300 errors. I have followed all the instructions and repairs that were listed. And I'm still getting the same error codes.
Things that I've done:
1. Cleaned EGR Valve and EGR Ports/Intake manifold.
2. Replaced Coil Pack, Plugs and Wires
3. New air filter (Monster Flow)
4. Check engine compression (tested OK)
Relevent setup:
1. JR Racing Header
2. RB Mid-racing pipe + RB Dual exhaust (Pipe was drilled to insert the O2)
3. (No cats)
Symptoms:
1. When the car first starts up (Cold) and the auto-choke is on it feels like the throttle response is what it should be or as close to it as I've seen in a while.
2. Once the auto-choke goes off any time I press the gas pedal the car acts as if it wants to stall. (Very hard to get the car to start moving from a dead stop) (sometimes misfiring once every other week)
3. Once the car has been driven for about 10 minutes it drives OK but still not like it should; but it is drivable. (but still not that good from a dead stop)
The car acts like it has no power and no torque.
Past problems possibly related:
1. I had the timing belt replaced around 105K. When that was replaced the mechanic that installed it dind't put the crank case or valve cover back on correctly, causing the car to spew oil. After I realized there was a problem my car had over heated one time. I didn't think much of it since it still had the original hoses on it. So i cut the part of the Heater hose that had busted and put it back on went about my business. A few days or a week later a different hose busted. I then found out that it was leaking oil from the back of the head around the valve cover. (didn't know about the crank case not being bolted on until the new mechanic replaced the valve cover and timing belt again. I had him do a compression and leak down test on the motor which he says passed. Later on after I had these problems is when I added the exhaust. and about a week after that I got the CEl for the first time, so I thought it had to do with the lack of the O2 and thats when i had him drill the pipe and put an O2 in. A few weeks after that I made a road trip from Gainesvill, Fl to Dallas, Tx. the car did ok (Even with the CEL on) on the ride down. On the way back, Ii'm not really sure where it happened somewhere late in the trip maybe around Tallehassee, the "key" that holds the crank in place broke so needless to say my timing was way off (I couldn't tell because I was asleep at the wheel after 10 hrs+ of driving) So, I took it back to the mechanic and he hooked up a machine to it and told me its ok. He then had me take on the highway to test it to see how it did after he adjusted the timing a little. Well, never in my life have I seen a car decelerate on a 1/2 degree uphill incline @ about 90 MPH in a low gear. Anyway thats when I took it back and he took it apart and found the busted key. Ever since then the car hasn't really ran very well and has progressivly gotten worse. Since then I have done a compression test and it did check out OK.
I'm going to test the O2 sensors this weekend and see if those are causing a failure of sorts (Original sensors) after that I'm at my wits end and have no idea where to go with this problem. I'm not that far away from just biding my time with this motor until it goes and then buying a new motor to put in; but I would like to figure out what is causing these problems.
(On a side note: I have spoken with the guys at FM and they are very nice. I have since then purchased a Hydra from them per their recommendation. I don't really want to put it on just yet unless I can determine that it is the O2 sensor causing the problem. I don't want to foul-out the $300+ wideband O2.
Well, any thoughts on this would be appreciated.
