80's 454 fuel supply challenges
Long time first time. I have an 86 The Executive with a newish crate 454 and 95 Chev TBI on top of it. On a recent trip, we had some intermittent stalling except when I'd step on the gas at which p...
Forum Discussion
For TBI troubleshooting...
https://harristuning.com/Tbi/troubleshooting/
94-95 TBI years were 26-32psi fuel pressure. You also need to be sure you're running the correct flow rated injectors for your year engine. Only use AC Delco parts. Do not cheap out.
Even a bad TPS can cause the issue you're having.
You mention 220 - 280 temps?
The dash gauge even have 280? Or is it 260? It is normal behavior to see these era RVs go as high as ~240 on long grade pulls. What is important is to be certain you hear the clutch fan kicking in. That is what prevents the temp from boiling over. A normal operating range on the flats is generally 205 - 217 or so. Your dash gauge will rarely reflect that accurately. Usually read higher by as much as 10-2X degrees depending on ambient temp.
Water also cools better than coolant so get the ratio at min 50/50 (distilled water). Pre-mix is already mixed with distilled water. With 454s I like 60 percent water vs 40 percent coolant.
Those year coaches run with a 195 T-stat. Do not use one less than that. It will throw off the PCM. I'd also pull the distributor and replace the pick-up coil and visually inspect the stator ring. The ring is known to crack messing with timing.
https://harristuning.com/Tbi/troubleshooting/
94-95 TBI years were 26-32psi fuel pressure. You also need to be sure you're running the correct flow rated injectors for your year engine. Only use AC Delco parts. Do not cheap out.
Even a bad TPS can cause the issue you're having.
You mention 220 - 280 temps?
The dash gauge even have 280? Or is it 260? It is normal behavior to see these era RVs go as high as ~240 on long grade pulls. What is important is to be certain you hear the clutch fan kicking in. That is what prevents the temp from boiling over. A normal operating range on the flats is generally 205 - 217 or so. Your dash gauge will rarely reflect that accurately. Usually read higher by as much as 10-2X degrees depending on ambient temp.
Water also cools better than coolant so get the ratio at min 50/50 (distilled water). Pre-mix is already mixed with distilled water. With 454s I like 60 percent water vs 40 percent coolant.
Those year coaches run with a 195 T-stat. Do not use one less than that. It will throw off the PCM. I'd also pull the distributor and replace the pick-up coil and visually inspect the stator ring. The ring is known to crack messing with timing.
