Finally bringing myself to ask for some help tracking down this issue with my 17 year old son's daily driver. 180k miles..... the motor stumbles/ hesitates on light acceleration and has a low/rough idle, but only in the summer?? It runs like a top when its cool / cold outside. Outdoor temps get in the 80s and the issues return.. but not always.... about half the time it runs fine. We have been chasing this problem for over a year now, and all of our efforts have failed to remedy the problem.
There is No CEL. When we first bought the truck it had a bank 1 lean code which went away after some of our efforts below. I think when we replaced the fuel pump.
Parts that my son and I have replaced over the last 12-18 months trying to fix the issue: fuel pump, injectors, fuel filter, ignition coil, distributor cap, adjusted timing, replaced pcv valve , replaced 02 sensors. fusible link + junction block,. checked spark plug wires, checked spark plug gaps. checked all vacuum lines. EGR delete was performed by a shop in March 2021 when i first acquired the vehicle. Otherwise we have done all the work ourselves.
I tried to lay it out to the best of my knowledge, but if there is any other info that would be helpful in diagnosing this issue please let me know and i will try to track it down. Any ideas or advice or just a point in the direction of a resource would be massively appreciated. I'm running out of ideas!
There is No CEL. When we first bought the truck it had a bank 1 lean code which went away after some of our efforts below. I think when we replaced the fuel pump.
Parts that my son and I have replaced over the last 12-18 months trying to fix the issue: fuel pump, injectors, fuel filter, ignition coil, distributor cap, adjusted timing, replaced pcv valve , replaced 02 sensors. fusible link + junction block,. checked spark plug wires, checked spark plug gaps. checked all vacuum lines. EGR delete was performed by a shop in March 2021 when i first acquired the vehicle. Otherwise we have done all the work ourselves.
I tried to lay it out to the best of my knowledge, but if there is any other info that would be helpful in diagnosing this issue please let me know and i will try to track it down. Any ideas or advice or just a point in the direction of a resource would be massively appreciated. I'm running out of ideas!