The center electrode on that #5 plug looks like it's significantly shorter, and the ground electrode looks like it's been running hotter.
My 454 Rebuild
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I think that's just the angle of the pic making it look that way.
Mangonesailor
I'm Awesome
Nah, #5 is covered in schmoo and only part of the electrode is sticking out of it.
Poke it with a pick, see if it's carbon
Poke it with a pick, see if it's carbon
As i mentioned earlier. These are a set of old high mile plugs that have been in the new engine to just check and make sure the new plugs were not the problem.
Next weekend i'll be putting the new plugs back in.
Also i have 2 new regulators coming the AcDelco FP10021 and the Deatschwerks. 1 of these better give me the proper fuel pressure!
Going with the part cannon i have also bought a set of stock rebuilt fuel injectors. I know rebuilt ones are a roll of the dice but spares are nice to have if no other reason then spares and future need sense i plan on buying another GMT400 with a big block this summer some time.
Next weekend i'll be putting the new plugs back in.
Also i have 2 new regulators coming the AcDelco FP10021 and the Deatschwerks. 1 of these better give me the proper fuel pressure!
Going with the part cannon i have also bought a set of stock rebuilt fuel injectors. I know rebuilt ones are a roll of the dice but spares are nice to have if no other reason then spares and future need sense i plan on buying another GMT400 with a big block this summer some time.
The FPR on the right i bought last fall is a Beck/Arnley brand and will only pressure up to 46/47 ish psi.
The new AcDelco FPR on the left looks exactly like the other one.
The old one also had the exact same O rings on it. They are exactly the same on the outside. Hope they are different on the inside!
The new AcDelco FPR on the left looks exactly like the other one.
The old one also had the exact same O rings on it. They are exactly the same on the outside. Hope they are different on the inside!
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Got the FPR and injectors changed and it is about the same but FP is at 58PSI.
Fuel trims are WAY wonky but that's to be expected with more fuel pressure and stock injectors. I guess the ECU will need to relearn over the next few days.
Right now the LTFT for both banks are in the high negative double digits but slowly coming down the more i drive it.
Fuel trims are WAY wonky but that's to be expected with more fuel pressure and stock injectors. I guess the ECU will need to relearn over the next few days.
Right now the LTFT for both banks are in the high negative double digits but slowly coming down the more i drive it.
Here is a pic of the fuel trims driving a steady 60mph.
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Mangonesailor
I'm Awesome
Keep us posted after a few days of driving to see what your trims are. If you had tuning software you could remap the VE table and not have to fiddle with tweaking the FPR, should you feel the need to.
That's neat though, maybe I'll swap mine to an adjustable one since I think mine is doing the typical hard-hot-start thing.
Fuel trims are still high in the - around 15% LT.
ST is + - 1%.
After researching all week i think i understand it like this.
LTFT is what actually controls rich/lean. STFT is just minor immediate adjustments to maintain what the LT is commanding.
After watching some video's on youtube university im wondering if what i thought was a mechanical problem of some sort is actually a electrical problem.
One video of a ferd with high - fuel trims turned out to be bad wiring at the PS pump pressure sensor. The 5V and negative were shorting together and causing symptoms very much like my truck.
I don't have nowhere near the sensors of a newer truck of any kind but im wondering if this could be a possibility on my truck with one of the sensors i do have?.
Something is telling my ECU that the engine is running rich i think.
All 4 O2 sensors appear to be working properly but they are 25 years old.
The MAS is reading 7.4ish g/s at hot idle and if i rev it with no load to 1200rpm it reads 14ish g/s. Seems normal to me but maybe not.
Every sensor i can see with Torque pro or Dash Command appears to be working as intended so i have no clue where to start looking.
ST is + - 1%.
After researching all week i think i understand it like this.
LTFT is what actually controls rich/lean. STFT is just minor immediate adjustments to maintain what the LT is commanding.
After watching some video's on youtube university im wondering if what i thought was a mechanical problem of some sort is actually a electrical problem.
One video of a ferd with high - fuel trims turned out to be bad wiring at the PS pump pressure sensor. The 5V and negative were shorting together and causing symptoms very much like my truck.
I don't have nowhere near the sensors of a newer truck of any kind but im wondering if this could be a possibility on my truck with one of the sensors i do have?.
Something is telling my ECU that the engine is running rich i think.
All 4 O2 sensors appear to be working properly but they are 25 years old.
The MAS is reading 7.4ish g/s at hot idle and if i rev it with no load to 1200rpm it reads 14ish g/s. Seems normal to me but maybe not.
Every sensor i can see with Torque pro or Dash Command appears to be working as intended so i have no clue where to start looking.
Maybe its time to replace the upstream sensors? I've heard they may function 'normally' but be slower in responding, or something along those lines.
Disclaimer: I've no evidence of this assertion beyond echoing what I've read elsewhere on here from presumably smarter, more experienced folks.
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