Engine problems
Was it running fine and normal before it went all sluggish on you? Was it right after the work you described was done, or on some other timeline?
And I suppose I could dig deeper, but what vehicle and engine is this? I see references to '91 and '92, but what exactly are we talking here? A 5.0? 5.8? 4.9? A 2-wheel drive or four? Standard cab, Super-Cab or Crew-Cab?
Sounds like a V8, since you said upper and lower, but what prompted the change and what is the difference between the two? And were the injectors a different size/style than the earlier ones?
Not that some of those things will be pertinent here of course, but it's nice to know anyway just in case something clicks in a memory that might help us diagnose the issue.
If the injectors are too big or too small and the computer is not expecting them, maybe it's trying to run lean/rich and doesn't know why.
If a V8 and the particular year uses a TFI module, and the something is telling the module that it's in cold-mode and limiting overall ignition timing it could cause the hot exhaust. Too much fuel being left in the exhaust could do it too. Not sure an overly lean condition could do that, but I suppose it's possible. More likely late burning and incomplete burning letting some of the burning go on in the exhaust.
Anyway, I'm just spitballing here. Someone with more experience might know. But giving some of that extra info might help.
Good luck.
Paul
Was it running fine and normal before it went all sluggish on you? Was it right after the work you described was done, or on some other timeline?
And I suppose I could dig deeper, but what vehicle and engine is this? I see references to '91 and '92, but what exactly are we talking here? A 5.0? 5.8? 4.9? A 2-wheel drive or four? Standard cab, Super-Cab or Crew-Cab?
Sounds like a V8, since you said upper and lower, but what prompted the change and what is the difference between the two? And were the injectors a different size/style than the earlier ones?
Not that some of those things will be pertinent here of course, but it's nice to know anyway just in case something clicks in a memory that might help us diagnose the issue.
If the injectors are too big or too small and the computer is not expecting them, maybe it's trying to run lean/rich and doesn't know why.
If a V8 and the particular year uses a TFI module, and the something is telling the module that it's in cold-mode and limiting overall ignition timing it could cause the hot exhaust. Too much fuel being left in the exhaust could do it too. Not sure an overly lean condition could do that, but I suppose it's possible. More likely late burning and incomplete burning letting some of the burning go on in the exhaust.
Anyway, I'm just spitballing here. Someone with more experience might know. But giving some of that extra info might help.
Good luck.
Paul













