mechanic didn’t show up today…but i’m gonna try to pull the codes myself…i will let y’all know…
There’s just not much to say without the codes or an in-person diagnostic. I will suggest, in response to circuitsmith’s comment about voltage, that if you only have one or two bad cylinders, it is probably just that cylinder, and you should think about plugs and wires, then fuel. If you get codes for all the cylinders, or codes for other things in the engine, you might want to think about a general ground or voltage problem.
Okay fellas…I finally went and got a code reader…and I pulled the codes. There are 2 codes, one is p0303 and the other is p0303pd which I think means pending. Check engine light is still on but not flashing, and engine is still erratic but it’s seeming to get better with time…less rumble. Any more information would definitely help. I’m hoping it’s just wire and plugs still… Can anyone tell me if it is for sure before I take it to a mechanic? My mechanic has been a no show for 3 days now, and I don’t want to get it to a shop and they tell me its some off the wall problem that’s gonna cost me $1,000 to fix. Thanks in advance for your help!!!
please …anyone???
P0303 says a #3 miss-fire. As to exactly what the problem is…sorry…but it’s impossible to tell over the internet. You need a mechanic to actually look at it.
You have a misfire when it rains. This isn’t terribly complicated, although you might find more than one issue. Replace your spark plugs & wires & drive on. Perhaps worry about the ignition coil that feeds #3 as well.
Well, here we go again!! I already replaced my plugs and wires…took it to a shop, cost a pretty penny, now…It hasn’t rained since then, that was until last night!
This morning I started my car up and I got that jumping feeling and my CEL started to flash…I turned it off and hooked up my code reader and got a p0306 and a p0306pd…code. Can anyone tell me what the pd means? Doesn’t give a good enuff explanation in the book.
Anyhow… I try to start my car again and it fires up fine…no rumble. So I clear the code and get to driving along…suddenly my traction control system turns itself off (which it has never done before) and I can’t turn it back on, and the traction control light off on my dash stays on every time I drive the car, won’t turn off, and can’t turn on my traction control either
Shortly after that, my cel starts flashing again ( while I’m driving) but my car is running normal at this point. Then it stops flashing for a sec and stops and never comes back on. Also, I noticed that my brake lights are now out when they were working fine last nite. Could this be some short in my electrical system somewhere?? Is there a particular place I should look for this short? Could it be a mere fuse? I don’t know, but it is really starting to add up!! Any helpful advice on what to look for will be greatly appreciated. Thanks in advance!!!
Please help me!!!
P0306 is a miss-fire detected on cylinder #6. If the spark plug and wire check out, then the problem could be the coilpak. Take a spray bottle with nothing but water in it, set it to mist, and mist around the coil and wires with the engine running. It should start acting up when you mist near the problem area. You may even see a spark jump out.
I’m with Busted on this. I do want to add that if the coil pack checks out, the injectors are also a possibility.
By the way, what exactly did the shop check? Does it say on the shop order? For a problem like this I’d have thought they’d check the spark pulses on a scope. And I’d have thought they’d use a spray bottle.
@ same Well, when I went to the shop, I told them my problem. They told me what I heard here… If I am getting a p0303 code, it’s probably plugs and wires, especially if the problem occurs when or after it rains…but could also be numerous other problems, which they tried to charge me an arm and a leg to check out. I couldn’t pay for it at the time. Looking back, I should have spent the extra 100 dollars to do it!!! I am going to change the coilpak next to see if that works. After that, it’s on to injectors I guess.
Any other suggestions at this time are definitely appreciated. By the way, any reason my traction control should b acting up like that? Every time I turn my car on, the traction control light turns on and my traction control turns off. Can’t turn it back on!!! Symptom of a problem or a problem itself. Also today my turn signal was stuck solid for a while. Oh, and I changed the bulbs on my brake lights. They are still out but the tail lights work and come on in the dark. What could be the problem…fuse…electrical control problem??? Any help will do. Thanks!!!
Coilpack’s tend not to be cheap. They’re cheaper than replacing the car, sure, but still.
You’ll probably still be better off getting it diagnosed properly, rather than just throwing parts at it. Having said that, for every part you replace, that doesn’t fix the problem, at least you’ll have spare parts, right? We all want to have a spare part for everything that can fail stored somewhere.
@flashing_lights.
I’m not sure if you ever solved your problem, but I’m having very similar problems with my own 1997 Buick Park Avenue. Though I haven’t had any luck solving the engine problem, (other than to never drive it in the rain for long) I have had some success with my traction control system. After hooking it up to an actual GM computer, I found my back left anti-lock brake sensor wasn’t getting any connection to the computer. I jacked it up and found that my just in front of the rear axle coming out of the body is a connection cable to the sensor with plugs on both ends. Both ends seemed to be very tarnished but only on the side for the left senor. I pulled the whole wire off and found that the black wire had the oddest corrosion I’d ever seen on a copper wire. Instead of being the normal tarnish you’d see, it was completely disintegrated into a red powder. I’m not sure what caused it but I replaced the wires from the harness in front of the axle all the way to the sensor and have not had a problem since. Hope this helps!
TL:DR For your traction control problem, check the wiring harness in front of the rear axle under the car and the wires running to the senor on each brake drum and replace if necessarily.
Just to answer your question on pd, it means pending. For the CEL to come on, a code needs to be detected twice. The first time is the pending code. If the conditions occurs a second time within three drive cycles, the CEL comes on and the code is set. If it does not reoccur, then it is deleted from memory.
The traction control will be disabled when the check engine light is on. Its just the software. Concentrate on the misfire codes and fix it before you wreck the converter. Been there done that.
Honestly I havent had the problem for a while now but then again it has stopped raining since then. I am sure it will return and when it does I will update this thread. I have taken it to a shop and they want too much to try to figure out this electrical problem so when the code and problem returns I will update this thread. @ Behemecoatyl ty so much for your suggestion…any relating info is def valuable info and if/ when the problem reoccurs I will update this thread. Ty all!!
I’m having the same problem with my 2000 Buick lesabre its idling and the service engine light is blinking got it put on autozones diagnostic and these codes came up p0300 p0420 and p0440 any help my mechanic thinks its one of my coils but the machine is not specific on which coil
P0300 is a random misfire code . . . since the light is flashing, it means the misfire is severe enough to potentially damage the catalytic converter. Someobody with a high level scanner is going to have to check exactly which cylinder(s) are the real problems
P0420 is bank 1 catalytic converter low efficiency code. Again, this requires proper diagnosis, not a “shotgun just throw parts at it” approach
P0440 is an evaporative emissions “gross leak” code. This should be fairly easy for a competent mechanic to diagnose and repair. Might be a bad gas cap or a purge valve with a blown diaphragm. You want somebody who knows how to diagnose the car, not a guesser. If your cap is missing or has an obviously split seal, that may very well be your one and only problem, as far as this code goes. But if that is not the case, then a proper diagnosis is needed
Your problem is inigation coil. Also tied in with your ECM Electricon Control Mog.(car brains), the flashing light means miss in a coil…
You’re getting a little ahead of yourself
There are many things, which could result in a severe misfire