Mechanics

CAR RUNS ROUGH AT IDLE. NOW DIES AT IDLE.

2001 Saturn L300

Engine Performance problem
2001 Saturn L300 6 cyl Two Wheel Drive Automatic 150000 miles

If I keep my foot on the gas it runs. As soon as I stop it starts choking and dies. I released pressure from the check valve and some gas came out so I know I had pressure. To be sure I took the fuel filter off then tried to start it. Gas shot out really good so the fuel pump is ok. Blowing air through the fuel filter (with my mouth) is possible although difficult. There are no other symptoms that I can see of the problem. It had done the sputtering at idle a few times before but it never died. This time it died while I had the hood up looking at it. Now when I try to start it if I keep my foot on the gas it will stay running. As soon as I take my foot off it dies again. I checked the air filter. It was clean. The Mass Airflow sensor was replaced a year or so ago (as well as the fuel pump). The spark plugs were replaced a year ago. I'm not sure what the problem is. I read someone else having similar symptoms had a problem with their " canister purge valve". Do you think this is a possibility? How can I check the valve? Are there any other things that I should check?
This car is getting older and I have put a ton of money into it (even though I saved a lot by doing the work myself) so I'd rather not take it to a mechanic if it's something I can handle.

Thanks a ton,
Cory
Avatar
Ssjcory
June 29, 2010.



If it's difficult to blow threw your fuel filter then I would replace your fuel filter it's restricted. All so I would rent a fuel pressure gauge and see what the actual pressure is rather then it squirt's fuel. It could be low be good enough to squirt fuel. Also see if you can rent a scan tool to see if you have any code's. Auto zone has tool's for rent. That's where I would start.

Saturntech9
Jun 29, 2010.
I am going after work to get a fuel filter. Figured its 10 bucks what the hey. I ordered a scan tool online this morning it ran me like 45$ but I figure its good for any obd2 vehicle. I think my father in law has a pressure gauge. Thanks for your response I really appreciate it. I'll reply here with my findings.

Tiny
Ssjcory
Jun 29, 2010.
Since I didn't want to wait until I get my scanner in the mail, I borrowed my buddy's scanner. So here's what I did.

First I installed the new fuel filter I bought. Then I started the car (it took a few since there was no pressure in the system). Once I got it to start it sputtered for a second but didn't die. So I gave it a few minutes and it didn't die. Then I plugged the scanner in and started the car again (no sputter this time). I see 2 error codes p0175 and p0172 which correlate with System Too Rich. I erased the error codes using the scanner. Then I proceeded to rev the engine and I let it run for about 20 mins. No errors came back up. I tried turning it off starting it a few more times. Still no errors or sputtering. It still sounds a little sputtery to me but NO WHERE near what it was. And the RPMs are stable at idle speed. I think maybe since the filter was so nasty it was keeping the fuel back from being pumped to the engine unless I put my foot on the gas causing enough pressure. The residual tiny bit of wierd sputtering might be some nastyness that got pushed thru the filter and is affecting some other fuel system component. Do you think buying a fuel system cleaner and adding it to the fuel could help? I think the fuel filter was the main issue. But i'm not sure. Any ideas?

Thanks,
Cory

Tiny
Ssjcory
Jun 29, 2010.
Glad to hear it's running better I bet it was starving for fuel volume wise with that old clogged filter.I would get a bottle of that chervon techroline cleaner in the white bottle it's close to 15.I would give that a try get yourself a good tank of gas like chevron gas and run a bottle of that cleaner thru it.

Saturntech9
Jun 29, 2010.
Thank you very much for your help, I will try that.
I'll post a reply here in a week or two to let you know how its running.

Thanks,
Cory

Tiny
Ssjcory
Jun 30, 2010.
Well I tried driving my car to work yesterday(since it drove fine around where I live). And the problem didn't show til after I drove about 30 mins on the highway. As I pulled into a parking spot at my work the engine started sputtering. On my way home it was doing it at stop signs/lights. So it looks like the fuel filter change / additive didn't fix the problem. When I got home I checked the filter (too make sure it wasn't clogged again that it might have been something nasty in my gas tank or something). It was as clean as when I put it in last week. My father in law came over and we looked at the throttle and when it opened he saw some build up inside. He suggested we get some throttle body cleaner. We did and we sprayed it all inside and some brownish liquid was coming out. I still have the problem though. I'm not sure what to check next. Any ideas?

Tiny
Ssjcory
Jul 7, 2010.
Check and see if you have any code's in the computer Also rent a fuel pressure gauge and see what your fuel pressure is.

Saturntech9
Jul 7, 2010.
Yeah my code scanner came in the mail today. I'll be scanning it when I get home. If I am able to get a fuel pressure gauge where do I check it? At the check valve on the rail?

Thanks,
Cory

Tiny
Ssjcory
Jul 7, 2010.
Yes right on the rail where the cap is. You can rent fuel pressure gauge's at auto zone.

Saturntech9
Jul 7, 2010.
Ok ran the scan on the car and have a bunch of trouble codes.

I'm not sure if any of these were caused by cleaning the throttle with TB cleaner and are just stored for an indefinite amount of time.

Here they are: P0102
MAF Sensor Circuit Low Frequency

P1510
Throttle Control System - In Limitation

P1516
TAC Module Throttle Actuator Position Performance

P0123
TP Sensor Circuit High Input

P0221
Throttle Position Sensor 2 Signal Range/Performance

MAF sensor was replaced a year or so ago (also it might be showing because we had taken the air tube that connects to the throttle off to clean it.

Do any of these codes scream this is the problem?

Thanks,
Cory

Tiny
Ssjcory
Jul 7, 2010.
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