P0300 Code. Here's my issue and question.
I messed with it some earlier tonight. I'm actually thinking it may be a vacuum leak now. I let it sit and cool off. I started it up and of course it was running rough so for just ***** and giggles I used a spray bottle and sprayd a little bit of water (it's all I had and I figure in small amounts won't hurt) around the intake and across the plug wires. I'm not completely sure what I sprayed but the damn thing nearly died. I let it sit for quiet some time again and tried to repeat the process to see if maybe I could pin point what I had sprayed to get it to die but yeilded no luck. I don't think I let it cool down enough maybe. I'm just confused and starting to get frustrated now so its time to just let it sit for the night and I'm going to drive my wifes yukon tomorrow. Any one got some other suggestions or ideas?
You may be on to something. Pull the PCV hose and plug it at the vacuum source. See if that cures your problem. If so, FIX IT! Don't run without a PCV. All kinds of nasty stuff stays in the crankcase without it.
Update: Car smells like rotton eggs and my tail pipes look like there filled with sand. I think I found my issue. The guy who owned the car before me said he had it tuned (which I don't know how credible he is) and may, or may not have tuned out the rear o2's which would be why I'm not getting the code. I guess I'll unplug the rear o2's and see if a code pops up. Thanks for all the input and ideas guys. I'll keep this updated.
Will do and the sad part is that I haven't worked at a dealership in like 3 years... since then I've been an A&P fixing airplanes... I've forgotten a lot now that I don't work on cars every day.
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Verdad Gallardo I drove down to the auto part store to scan the car after I unplugged both rear o2 sensors. No codes, so I guess he really did have it tuned. I guess it's time for a set of headers to go along with all those the other goodies I have just laying around in the garage.
this thread is insane.
those plugs and wires are over 12 years old? did you even try to remove them and take a look?
and why don't you replace that pcv line if you can see that it has collapsed?
and why don't you replace that pcv line if you can see that it has collapsed?
Last edited by BobDoLe; Jun 2, 2011 at 11:12 PM.
I did replace it. I was at work on my lunch break when I was poking under the hood and posted that comment. No I haven't pulled a plug or replaced them yet. My job keeps me so busy. I work 18 hour days 6 days a week. I don't have time, however, I have made time this weekend and it will get done. I just bought this car in February and the parts have been laying on my garage shelf since the weekend after I bought it. I intended to do this stuff but I just haven't had time and up till now it has ran relatively well. Especially since 2 months that I've owned the car it has just been sitting because I was in the field.
Put your wife on it..tell her to pop in a movie for the kids..put dinner in the croc pot, and start jobbin.
I don't think she'll girly the car up..you're already gay enough to do that.
I don't think she'll girly the car up..you're already gay enough to do that.
Last edited by the_merv; Jun 3, 2011 at 02:36 AM.
My wife wouldn't know where to begin. She wouldn't be able to get the hood open. Okay so thanks to my job I wasn't able to do anything with my car other than drive it to work and get pissed about how its running. I think the smell was coming from a different car while I was driving because I only smelled it once and I haven't yet again. Also, I cleaned all the dirt in my tail pipes and it has yet to return as well. I'm just really confused as to why it runs so bad but if I give it some gas the misfiring completely stops and it runs like it should, but, as soon as I back off the pedal and try to drive the car normal it starts acting up again. I've got new plugs, wires, o2 sensors and a magnaflow catback just siting in my garage. Should I be looking at something else as a possible cause?
Ok, another update. So my car has been slowly running worse and more often. This morning it was running so bad it almost wouldnt run. Now what I have always noticed is when its running bad if I give it alot of gas it will instantly clear up and quit. So, this morning while it was running bad I unplugged the tps, made no change, plugged it back in and it instantly smoothed out? Its not setting a tps code? Could it still be bad? Is this my issue?
TECH Apprentice
Joined: May 2004
Posts: 318
Likes: 14
From: Chicago, IL
You've got a lot of different symptoms than mine, but here's how I diagnosed my misfire (I've yet to fix it, need time).
So, my car would misfire everytime it rained or was extremely cool & humid out. It would eventually go away as I drive it, but sometimes took 20+ minutes to go away.
My buddy took his HP Tuners in the car with me as I went through a carwash with undercarriage wash (which was one way I discovered I could invoke it), and HP Tuners saw that my bank 1 O2 sensor stopped switching and would go completely out of range, and when it did that, my misfire started happening.
When I would go WOT during a misfire, it would usually clear up, but then it would come back when the RPMs came down. I have a regular Actron scanner that I could use to check the mV on the O2s and I was starting to suspect it was O2 since I did notice really strange values after a carwash so I was going to compare them, but thank God my friend got HP Tuners and we could watch it on screen.
Like the guy said, it could be anything, but especially if you have O2s lying around, I'd check that, or check your O2 switching with a scanner if you have it.
So, my car would misfire everytime it rained or was extremely cool & humid out. It would eventually go away as I drive it, but sometimes took 20+ minutes to go away.
My buddy took his HP Tuners in the car with me as I went through a carwash with undercarriage wash (which was one way I discovered I could invoke it), and HP Tuners saw that my bank 1 O2 sensor stopped switching and would go completely out of range, and when it did that, my misfire started happening.
When I would go WOT during a misfire, it would usually clear up, but then it would come back when the RPMs came down. I have a regular Actron scanner that I could use to check the mV on the O2s and I was starting to suspect it was O2 since I did notice really strange values after a carwash so I was going to compare them, but thank God my friend got HP Tuners and we could watch it on screen.
Like the guy said, it could be anything, but especially if you have O2s lying around, I'd check that, or check your O2 switching with a scanner if you have it.
^ Intersting. It's really odd to me that when I unplugged the throttle position sensor it didn't change the misfire but when I plugged it back in the engine idled up and it smoothed out. Now keep in mind that when I unplugged it it was misfiring and trying to idle at abot 300-400 rpm...
Any one else have an issue similar with the tps that never set a code?
Any one else have an issue similar with the tps that never set a code?
Teching In
Joined: Oct 2007
Posts: 34
Likes: 0
From: Mount Airy, MD
The vacuum leak has caused the engine to run false rich. it has been doind it for so long, that the cats have probably bit the dust(the sand hint hint). You NEED to fix the vacuum leaks, perform the tune up and probably replace the cats. At the very least drop the pipe and give them a visual inspection.
Chris
Chris