Intermittent starting issue

MARIA STINSON

MEMBER
2003 SATURN VUE
2.2L
4 CYL
2WD
MANUAL
150,000 MILES

I have replaced fuel pump (pressure regulator attached) and fuel filter. The SUV will sometimes start right up and sometimes crank for minutes then start. Sometimes it starts then shuts off. Sometimes it starts and stay going. With the key to on (engine off) there is no pressure at the fuel rail valve. (I have only checked it during trouble starting) when I crank it pressure will remain at 0 pressure. Then out of nowhere during crank it starts and pressure shoots to 60 immediately. Usually it stays running occasionally it shuts off.

Tuesday, March 16th, 2021 AT 11:53 AM

6 Replies

MARIA STINSON

MEMBER
8 POSTS

Also while checking the pressure with key to on( engine off) after the pressure shoots up to 60 within a minute or less it drops to 5.(Sometimes it takes a few try's turning to on position to get pressure) if the engine is started the pressure sits around 40 for a good while after being shut off.

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Tuesday, March 16th, 2021 AT 1:46 PM

KASEKENNY

MECHANIC
18,907 POSTS

If this is not a fuel pump issue as you have replaced it (even though that is what is sounds like) we need to see if the fuel pump is getting the proper voltage in order to turn the pump on. So let's go to the relay and check voltage coming out on the two wires highlighted. The green/white wire is coming from the ECM and should have 12 volts on it when the key is turned to the on position. Then the gray wire should have 12 volts on it as well which shows the relay is closing and sending the 12 volts to the pump.

Here is a guide that will help with testing relays:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

If the pump is getting the proper 12 volts when it should then the pump is the issue. I assume this is the same issue before the pump was replaced?

Let me know what questions you have. Thanks

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Wednesday, March 17th, 2021 AT 12:28 PM

MARIA STINSON

MEMBER
8 POSTS

Yes it is the same issue. I replaced the pump and filter and still have the issue afterwards. Right now the car is starting just fine and holding pressure a few tries later it may leak/drop all the pressure. Relay clicks when I cut on. And 12v from both wires.

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Wednesday, March 17th, 2021 AT 1:42 PM

KASEKENNY

MECHANIC
18,907 POSTS

Okay. Just to be sure, you are getting 12 volts when the vehicle is acting up? Meaning when the pressure is dropping to 0 is when we need to know if the power is getting pulled. If the pump is not the issue then I suspect it is a relay that is opening improperly or the control module is faulty.

So I would hook the meter up to these wires one at a time (or if you have two meters do both) then cycle the key until it acts up to see if we are losing voltage on one of them. Does that make sense?

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Thursday, March 18th, 2021 AT 6:29 PM

MARIA STINSON

MEMBER
8 POSTS

I just found code p0172 in the freeze data after the last start attempt followed by stalling. It's not registered in codes but shows in freeze data for that start up. Fuel injectors? You are right it sounds like pump to me but with just replacing the pump regulator and filter and then that code makes me think it could be injectors.

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Thursday, March 18th, 2021 AT 7:09 PM

KASEKENNY

MECHANIC
18,907 POSTS

Yep. That makes sense. You have an injector leaking which is why the pressure is dropping.

If you could get the engine started and keep it running it would be worth trying to clean them but if I were you, I would just change them at this point.

Below is the info on this code if you need it.

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