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Help: C32 not getting fuel in cylinders. Pumps work - starting fluid starts car
Hello everyone,
I've been struggling with this issue for about 2 months which left the car sitting. Yesterday after researching, I pulled the whole fuel pump assembly out of the tank to check for cracked hoses or loose wiring. Everything checks out good - both fuel pumps work - there's fuel in the rail as fuel gushes out when I quickly press in the shrader valve. It seems as though the injectors are preventing fuel from entering the engine. The car did start today on its own for 5 minutes. It idled well, revved well and then died and wouldn't start back up. Before it died it would drop in idle. Even with the gas pedal pressed in to give it fuel nothing would happen. What could it be? CPS? Intake sensor?
Well, I went ahead and ordered a Bosch Crankshaft Position Sensor. Part should arrive today so we'll see how that goes.
Good luck. Since you seem to have fuel in the rail when you start the car, something is cutting off the fuel supply. CPS, Fuel Pump, Pump relay, TB all play a role. CPS is a good beginning.
Good luck. Since you seem to have fuel in the rail when you start the car, something is cutting off the fuel supply. CPS, Fuel Pump, Pump relay, TB all play a role. CPS is a good beginning.
Thank you for your reply. I sure do miss driving it.
I'm going to install the new CPS tomorrow. The green wire plugging into the rear SAM seems to have slight corrosion on it so I'll try cleaning that also. One weird thing though is when the key is turned to the "ON" position, there's a repetitive clicking noise near the throttle body. It's not normal and I haven't figured out what it is yet. That may be something to look into.
No it wasn't the CPS unfortunately. My car had trouble starting initially until I lightly sprayed starting fluid at the throttle body and then it stayed running for about 5 minutes again and then died. I'm stumped... 😔
- Tried a different rear SAM
- There is fuel in the gas tank
The repetitive clicking is a giveaway that there is something wrong with the Throttle Body (TB) or the control of it.
Try a reset of the TB...it's free!
Go to the throttle body and unhook the cable going to it.
Turn ignition key to the stage right before the car starts (position 2). You should get an error on the dash (ESP Visit Workshop). Wait 20 seconds and then turn the key to the first position not off, leaving key intact.
Plug the cable back in.
Now put the key to the stage 2 (right before the car starts) and wait 3 min, the car will re-adapt the throttle body, and you will hear it move on its own. While this is going on, put everything back together.
Start car from position 2, and everything should be okay, tap gas pedal, rpm should drop normally, if they get stuck, or if you have a CEL, you did NOT do the reset correctly.
1. No fuel pressure at the rail today after connecting a fuel gauge to it. There's no pressure with the key turned to the "ON" position and no pressure while engine is cranking.
2. Both fuel pumps work and fuel is flowing out of the primary pump. I even ran 12V from the battery to both pumps while cranking and still no fuel pressure at the rail resulting in no start condition.
Since both pumps work and there's no pressure at the rail, that would mean that something is preventing flow in-between correct? What else is in-between besides the fuel filter and FPR? There are no signs of leakage. I replaced the fuel filter with internal FPR about 1.5 years ago. Could that be it?
@kbob - I looked at the TB but couldn't find the cable. I may have to take the cover off or pull the TB. I'll look deeper into it this weekend. Thanks for your help!
Another thing that I noted was that the fuel flow coming out of the primary pump wasn't a heavy gush but like a calm stream. Thinking that I should replace the fuel pump next.
Didn't you say that when you removed the Schrader valve you had fuel in the rail? If the pump is pumping, even if it is slow, the fuel will be filling up the rail and will be building some kind of pressure. What pressure did you measure? I think 50-55 PSI is normal.
Yes, it seems to be intermittent and is there suppose to be constant pressure from the rail with the key in the "ON" position? The gauge was reading 0 psi with the key turned to the ON and while cranking.
I hope the Schrader valve was removed before attaching the gauge.
Yes it was.
Figured out the issue. The main fuel pump is going out and runs intermittently even with running direct power to it.
Replacement pump is going to be a PIERBURG 722013020. Hope this helps someone else going through fuel issues. I'll provide update once the new pump arrives and gets installed.
Hello all. Received fuel pump today and installed it. Pump consistently runs and pressurizes fuel rail. Car starts every time but lags during acceleration. I'm resetting the ecu by unplugging the battery to see what that will do. The car lags like the supercharger pump is out. I'll check fuel pressure when I get off work to see where it's sitting at.
Hey all. Great update. Checked fuel pressure and it's at around 55psi which is where it should be. Turns out the lagging was coming from my rear SAM which was missing a relay in the #3 slot that controls the cooling pump. Without it, the car runs in limp mode due to the pump not working. I just forgot to replace that relay after swapping the rear SAM. In conclusion, the car is back to normal and runs amazing with the issue being a faulty main fuel pump. The entire repair costed me $151 USD.
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Help: C32 not getting fuel in cylinders. Pumps work - starting fluid starts car
