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P0300 Freeze frame data
I cannot wrap my head around this problem. When i bought the truck it ran great had power and would even squeal the tires with ease, then it started with the p0300. That was 5 months ago fast forward to now ive replaced
Cap Rotor Plugs Wires are good, have a new set to try anyway but they are all the same ohm Replaced spider with the updated one. Tried coil doesnt burn coolant or have a vacuum leak cleaned egr also watched it on the ethos seems to work Here is some freeze frames http://i40.tinypic.com/21mt72f.jpg http://i41.tinypic.com/vrd5xy.jpg Why are my short term trims so bad? I know its misfiring But why? http://i40.tinypic.com/6yfsr5.jpg http://img706.imageshack.us/img706/7595/23t3zug.jpg and some scopes of the o2's i think they may be next. Is this right? http://i56.tinypic.com/bedekj.jpg Another couple pics of it at idle http://i44.tinypic.com/34t252h.jpg The misfire chart, Its random http://i39.tinypic.com/242wfo5.jpg another freeze frame http://i43.tinypic.com/r1ep91.jpg Is the cam retard supposed to be -7? http://i40.tinypic.com/xbinbk.jpg http://i42.tinypic.com/2057af9.jpg Finally the truck in question, http://i54.tinypic.com/v4w5u9.jpg Please any help i have more but i think what i have should help. I think im missing something obvious |
Nice looking truck and I see you have some data to help. Welcome to the forum BTW.
This forum (and the people that contribute to it) is great. We have a diagnostic section that explains a lot of the codes that we get in these trucks. Unfortunately, P0300 is one of the hardest to track down. So many people have so many different experiences. Fortunately, most of them are documented on here. Please search for P0300 and you should find more information than you care to read. I actually just had a small bout with P0300 after an intake manifold gasket repair. Turns out #2 and #5 cylinders were not getting fuel because the poppet valves in the spider were stuck closed. |
Ive already exhausted every resource I can find by using google and multiple forum searches. Most end with injectors or the ignition system and seeing as ive replaced those they dont help at all. So ive posted the freeze frame data as to directly pinpoint the problem But nothing stands out to me besides the st trims and the cam retard which im working on right now.
Is the distributor a tooth off? Am i to pull it and rotated counter clockwise for more advanced or the other way? Long night lol :icon_couchhide: |
Have you done a compression check? Cylinder leak down test? Tested fuel pressure during operation while monitoring misfire count on the scan tool to see if fuel pressure drops out?
Maybe you should go through each and every test that you have done and the results for us. The P0300 code in the DTC section also links to another thread that runs through A LOT of different scenarios. It's a long read, but can be informative if you've already exhausted all other avenues. |
I did a compression test on cylinders 1 and 4 since they misfire the most. I tested the fuel pressure earlier tonight was 55-60 at idle and would raise as i accelerated. Ive noticed a few noises since i bought a new gates belt. Now i can hear something on the drivers side of the motor maybe that sounds like air is rushing through? It seems to affect the idle alot. But its most noticeable when the engine bogs after revving, it seems to hesitate when revving in nuetral.
New parts list Cap Rotor Plugs coil Verified spark Fuel filter Updated mfi injectors Verified fuel pressure at idle revving and under load driving and leakdown didn't budge (new regulator and injectors in kit) Cleaned egr and verified function with scantool Cleaned contacts on every plug i could find Cleaned maf Its new looking and works on the scantool I messed with the distributor and checked the gear and set cam retard as close to 0 possible. Was -7 now its -4 Ive checked for vacuum leaks at least a dozen times. Used up a couple cans of anything flammable It seems that it doesn't missfire as bad when cold but ive tried a coil Im thinking Plug wires have a set ready to put on or ICM? ECU? Sometimes the airbag light turns on but if i hit the horn goes off? Unrelated? I Just dont get it. I want to v8 swap this thing but id hate for it to come back and haunt me if its the wiring or ecu or something I just need to fix it Getting terrible gas mileage runs piss poor has no balls i feel someone has tampered with it before to try and fix it. ANY more help :icon_wink: |
Have you checked distributor shaft play? I've heard some came through with chinese bearings that like to fail and cause a hard to find P0300.
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It hardly moves side to side
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How many miles and what are the results of your compression test of all four cylinders?
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Originally Posted by Gale
(Post 483600)
How many miles and what are the results of your compression test of all four cylinders?
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after veiwing this thread and seeing what you have done to your vehicle and the data you have provided us, to me it seems your b1-s1 o2 is reading lazy. first i would check to make sure you dont have an exhaust leak at the manifold or donut @ downpipe as these would cause a lean condition. if that checks out ok i would be thinking about replacing both o2s as they recommend to change them around 100k. couple ways to check since you got a scanner with live data reading would be watch the o2 output while idle and rev it up abit 2500rpm taking note of the sensors. should be sharpe up/down. than introduce a vacuum leak by taking off a line and taking note again at idle and fast idle should be reading high. also i would be checking fuel pressure as well just to make sure. hope this helps
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