have to hold throttle all the way to the floor before starting. I have change fuel pump, throttle body, MAF, coolant sensor.
Apr 23, 2021 at 12:46 AM
Hard starting
WBG57
- MEMBER
- 4 POSTS
When you are holding the accelerator down you are doing what is called a clear flood start. This means holding the pedal down tells the PCM to cut injector pulse as the engine is most likely flooded.
I would start with monitoring the fuel pressure to start but just turn the key to on and let the pump prime the system and then do not crank the engine. We want to see what the pressure is and how long it holds it.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
I suspect the pressure will drop pretty quickly which means we either have a pump issue or a leaking injector.
We should also check for codes while we are at it.
https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing
Lastly we should remove the plugs and see if they are wet after doing this. If they are then that injector is most likely leaking. You could also use a borescope to look in the cylinder to see if you see any fuel.
Let's cover this and go from there depending on the results.
I would start with monitoring the fuel pressure to start but just turn the key to on and let the pump prime the system and then do not crank the engine. We want to see what the pressure is and how long it holds it.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
I suspect the pressure will drop pretty quickly which means we either have a pump issue or a leaking injector.
We should also check for codes while we are at it.
https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing
Lastly we should remove the plugs and see if they are wet after doing this. If they are then that injector is most likely leaking. You could also use a borescope to look in the cylinder to see if you see any fuel.
Let's cover this and go from there depending on the results.
Apr 24, 2021 at 8:25 AM
🔧 Tools & Auto Repair Parts
Find automotive tools, diagnostic equipment, and replacement
parts for your next repair.
Shop on Amazon →
Paid affiliate link. As an Amazon Associate, we earn from qualifying purchases.