alright, my truck has been acting up lately, and now its to the point that i cant drive it. The symptoms really have me stumped.the problem is intermittent, and does not really have ryhme or reason, however the condition seems to "like to" start at cruising/steady throttle.
Took of from a stop sign one day and she started missin, tunnin like , popping thru the tbi and backfiring. Limped home, looked it all over, went on test drives, tried my damndest to recreate it. No luck. It would do it off an on, and i noticed i could turn the key off, and back on (kick start it) goin down the road and things would go back to normal for a short period.
Eventually it completely went away (i assumed it was bad gas as it stopped after i filled up) for about 2 wks and even a 160 mile trip to pick up an engine
Now its back to doing it, except worse and now more often. It back fired yesterday and completely split my muffler case.
I managed to limp home and since then it has trouble just goin doen the block with out acting up. When it does, it acts like timing, and it also acts like pure electrical problems.
I pulled the plugs and found this
All plugs were carbon fouled, new plugs and wires later(i already had laying around), no change. I tested the coil and pick up coil with an ohm meter, both tested good. Swapped in another coil with no change. Verified timing at 0 with est unplugged. BUT i did notice the when running fine, the timing advance works just as it should, however when it start acting up the timeng advance doesn't advance properly. 1/2-3/4 throttle (with est plugged in like normal) and my timing mark is hanging out just a little passed 12 degrees. I would estimate 13-17 degrees whereas when its running normal, with the same throttle the timing mark shoots up to about 30ish (my last mark is 12 so its all an estimate)
I do suspect the issue is not only tied with timing, but also voltage... I noticed various voltage issues lately like reading 13.7 at the alt but around 11-12 at the battery.
This past winter i could drive into town at night and when i turned my blower to high (resister is bad so all i have is high) the radio would ahut off and come back on. If i turned the headlights on, same thing. Sometimes it would do it, other times the radio stayed on
2-3 months ago my speedo started acting funny. I could be at a standstill and it read im doing 80, it would jump around. This problem started real slow and has progressed. It started as just a momentary glitch while i drove.and even then it was just every now and then. Maybe once a wk. then it got to where it would do it for the whole trip into town. Now when it does it, the speedo needle just dances around. Sitting still, driving, and ive noticed that the running issues "seems" to corrilate with the speedo. Not EVERY time but the majority of the time, if the speedo is dancing is when it starts backfireing and cant handle any sort of load. The times that speedo is acting notmal, the truck runs like a top.
A couple times in the last few days the radio would just randomly off and turn back on, my voltage gauge on the dash (most of the time) reads around 12-10v (it has always read alt voltage of 13.5-14.7)
Its hard to tell if i have a voltage issues that making componets act wierd and throw things off, or if i have a fualty component thats shorting out tge rest of the system. I do suspect with the lack of toming advance when it does act up tho leads me to beleive a fualty ESC, but i cant find a single test one in chillton or on ALLDATA for the ESC. I do get an ESC code under heavy load conditions for my knock sensor that hasnt been there since i bought the truck 4 years ago. I assume it's irrelevant. But from text ive also read that the ESC can retard the timng by about 20 degrees which seems like the amount of degrees different in the timing mark between running good and running bad.
Anybody care to weigh in?
Took of from a stop sign one day and she started missin, tunnin like , popping thru the tbi and backfiring. Limped home, looked it all over, went on test drives, tried my damndest to recreate it. No luck. It would do it off an on, and i noticed i could turn the key off, and back on (kick start it) goin down the road and things would go back to normal for a short period.
Eventually it completely went away (i assumed it was bad gas as it stopped after i filled up) for about 2 wks and even a 160 mile trip to pick up an engine
Now its back to doing it, except worse and now more often. It back fired yesterday and completely split my muffler case.
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I managed to limp home and since then it has trouble just goin doen the block with out acting up. When it does, it acts like timing, and it also acts like pure electrical problems.
I pulled the plugs and found this
You must be registered for see images attach
All plugs were carbon fouled, new plugs and wires later(i already had laying around), no change. I tested the coil and pick up coil with an ohm meter, both tested good. Swapped in another coil with no change. Verified timing at 0 with est unplugged. BUT i did notice the when running fine, the timing advance works just as it should, however when it start acting up the timeng advance doesn't advance properly. 1/2-3/4 throttle (with est plugged in like normal) and my timing mark is hanging out just a little passed 12 degrees. I would estimate 13-17 degrees whereas when its running normal, with the same throttle the timing mark shoots up to about 30ish (my last mark is 12 so its all an estimate)
I do suspect the issue is not only tied with timing, but also voltage... I noticed various voltage issues lately like reading 13.7 at the alt but around 11-12 at the battery.
This past winter i could drive into town at night and when i turned my blower to high (resister is bad so all i have is high) the radio would ahut off and come back on. If i turned the headlights on, same thing. Sometimes it would do it, other times the radio stayed on
2-3 months ago my speedo started acting funny. I could be at a standstill and it read im doing 80, it would jump around. This problem started real slow and has progressed. It started as just a momentary glitch while i drove.and even then it was just every now and then. Maybe once a wk. then it got to where it would do it for the whole trip into town. Now when it does it, the speedo needle just dances around. Sitting still, driving, and ive noticed that the running issues "seems" to corrilate with the speedo. Not EVERY time but the majority of the time, if the speedo is dancing is when it starts backfireing and cant handle any sort of load. The times that speedo is acting notmal, the truck runs like a top.
A couple times in the last few days the radio would just randomly off and turn back on, my voltage gauge on the dash (most of the time) reads around 12-10v (it has always read alt voltage of 13.5-14.7)
Its hard to tell if i have a voltage issues that making componets act wierd and throw things off, or if i have a fualty component thats shorting out tge rest of the system. I do suspect with the lack of toming advance when it does act up tho leads me to beleive a fualty ESC, but i cant find a single test one in chillton or on ALLDATA for the ESC. I do get an ESC code under heavy load conditions for my knock sensor that hasnt been there since i bought the truck 4 years ago. I assume it's irrelevant. But from text ive also read that the ESC can retard the timng by about 20 degrees which seems like the amount of degrees different in the timing mark between running good and running bad.
Anybody care to weigh in?
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