Dodge SRT Forum banner
1 - 20 of 25 Posts

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #1 · (Edited)
HELP: Car is MISFIRING

OK my car has been giving me problems for the past couple days, this will be long.

First things first. I had my car running on the flashing gas light the other day and I went to a gas station I usually don't go to and put $10 of 91 octane. This gave me a little over a quarter tank of gas. I drove the car about 3 miles and then ended up at home parked. Later on I drove my GF to work, which is about 4 miles away and then on the way home I went WOT at a wopping 15PSI of boost and below 10:1 AFR the car sputtered/popped a little. The car started to misfire so I pulled over on the freeway and gave some rev and heard it misfire even while revving. So I turned the car off and sat for a little while and re-started it and it revved at idle pretty easily so I tried to make it home, since it was only 4 miles away.. On the way the car started to flash the malfunction light so I stopped and checked my plugs and everything under the hood, it all looked good. I limped home and got there.. When I got there I checked the code that was now stuck on my dash, P0300.. After this I did a compression test fearing the worst.. but the compression test showed a 150 psi~ compression across all four cylinders.

The next day after reading up on all of this I read that it could probably be a few things.. Plugs/Wires/Coil/Bad Gas the usual suspects, with a TPS issue on the side. My TPS has never gave me troubles and I never got the code related to it. So I doubt it was that. I swapped out my stocker Coil which i've had in the car for a while for the ScreaminDemon coil which didn't give me any problems while I had it.. drove it around and it started up again after 20 seconds of driving. I swapped my NGK plugs for old stocker Champions.. same deal. Now it was on to the gas..

I don't have a syphon (sp) tool so I couldn't get the gas I have in the car out, so I've been idling the car trying to get most of the gas to burn up before I fill with some new 91 octane, hoping its the gas.. now I've been going out and just turning the car on idling every so often and its been going down.. I'm at 1/8th tank now! wooh. As I'm idling for 3 mins.. I see smoke from the side of the car.. go damnit! So I turn the car off immediately and begin pulling my plugs.. I pull 1, 4, 3, and then.. 2. When I pull #2 I see smoke flowing from the #2 cylinder :crying: . After this I wait for a while and do another compression test KNOWING IT'LL MAKE ME CRY. Well, I did the test and to my suprise.. compression is STILL at 150~ across all four cylinders.

Now I am clueless on what else to try.. What could the problem be NOW?

I've swapped out Ignition Coil, Spark Plugs & spark plug wires.. all of which weren't the problem with the misfiring.. and NOW I'm smoking.. with 150 compression in all four cylinders, help.

Ralph
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #3 ·
NIVO88T said:
clogged turbo return line? caused the turbo to go bad? is it oil smoking?
I can't tell which color it is right now, its dark out.. I don't know if its oil or water just yet. The turbo is pretty new, I dunno yet if I should pull it off to check it, I'll make sure theres no other options before I do that. I'm thinking I should try checking the PCV..

What would cause only one cylinder to smoke, and not the other 3?
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #4 ·
Anyone know :(?
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #6 ·
ViscousCircles said:
I had a problem with my car smoking and mis-firing, It turned out to be a bad tank of gas. Hopefully you have the same problem. Good luck.
Whoaa, your car SMOKED because of the bad gas? I hope this is the case, seriously. I'm going to just go buy a pump and get the damn gas out of the car and try and start her up.. I'll update the thread if this works or not tomorrow :).
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #8 ·
Update: I drained pretty much all of the fuel out of the car, the gas light was blinking and the line was below the LAST line on the gas gauge. I got 2.5 gallons of 91 octane from a 76 and put it in.. Started it up and drove around the block and just as I was getting back to my house it started up again. Maybe I didn't put enough new gas? What do you think?

Also, the smoking has seemed to stop.. but I didn't let the car get fully warmed up or anything.
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #10 · (Edited)
Greg_04-SRT4 said:
Since you have no siphon to get the gas out why not dump in some octane booster? In case the gas is watery. Then fill up with good gas at your normal station.

worth a shot :)
UPDATE:

Well I got the gas out, and filled up 3/4ths tank of fresh 91 octane.. Same things happen. Looking at the service manual here are possibilities for the misfire (P0300)

IGNITION WIRE - Swapped good set, same problems
ASD RELAY OUTPUT CIRCUIT (COIL)
ENGINE MECHANICAL PROBLEM
- Compression is 150~ in all 4 cylinders
IGNITION COIL
- Swapped, same problems
COIL CONTROL CIRCUIT
SPARK PLUG
- Swapped out spark plugs for some good used ones, same problems
CHECKING FUEL PRESSURE
- Fuel pressure is fine, I have a gauge on my FPR
FUEL PUMP INLET STRAINER PLUGGED
RESTRICTED FUEL PUMP SUPPLY LINE
FUEL PUMP MODULE
- Still have the stocker, might try this soon
CHECKING FUEL LEAK DOWN
FUEL INJECTOR OPERATION
ASD RELAY OUTPUT CIRCUIT (INJECTOR)
FUEL INJECTOR
- Will probably try another set of S1 injectors ..
INJECTOR CONTROL CIRCUIT
PCM (IGNITION SYSTEM)
PCM


I guess I'll keep working at it.. Whats weird is it is fine at start-up.. it can idle forever just fine. After driving it around the block it'll start acting up and sound like its a motorcycle and then it'll also keep doing it at idle.. til I turn it off for a while. Maybe this can help someone help me diagnose the problem!

I wish I still had a warranty :ninja:
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #12 ·
I'm going to be recording/encoding a video tomorrow sometime so you can hear what happens and hopefully someone can point me in the right direction. :)

Stay tuned :(
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #14 ·
smoger said:
i know its a dumb suggestion prolly but have you reset the pcm since getting the new gas?
I've done that a few times, same thing though.. I hate this car :buah:
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #15 ·
Okay I haven't tried anything else, been pretty sick. Here is a video of what the car does.. It starts up fine,and idles fine -- no stumbling when I first start the car and let it idle for whatever amount of time.. the AFR is fine at 14.7-15.2. After starting to drive with or without boost after a few blocks (but in the video, the first few seconds..) the car bucks and the misfire is obvious.. you can hear the tone change while driving, it sounds like a motorcycle or a oldschool VW Bug. The AFR starts to look leaner than normal being around 15.5+ while driving/idle. The ignition timing, according to the powerpaq, looks the same before and after the misfire occurs.

I hope this video can help someone help me. :(.

Right click, save as -- http://www.allbozz.com/ralph/srt4misfire.wmv
 

·
Registered
Joined
·
53 Posts
I think you found your problem if the car goes lean as soon as you ride around the block then it has to be something in your fuel delivery system, clogged line, low pump pressure,fuel injectors or maybe fuel filter.do you have an exhaust temp gauge if so whats your egt while driving around.
 

·
Registered
Joined
·
1,026 Posts
Discussion Starter · #18 ·
Okay the video is now working, I re-upped and checked it..

Right click, save as -- http://www.allbozz.com/ralph/srt4misfire.wmv

As for the fuel delivery, I hope so.. I'm going to swap out the injectors for my old stock injectors in a few minutes. The fuel pressure is fine before and after, I've checked it -- theres a gauge on my FPR.
 

·
Registered
Joined
·
11,152 Posts
Your airfuel is not consistent from what i seei n that picture. The a/f should be around 14.7 even when your at cruise off boost.

check your powerpaq, its not tuned in correctly. Try adding some fuel to it to get the # down.
 
1 - 20 of 25 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top