getting too much fuel?

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Jan 24, 2012 | 09:58 PM

LigHtEmUp01

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getting too much fuel?

my car is getting way to much fuel and is fouling plugs causing rough start. what could cause this?

Jan 24, 2012 | 10:22 PM

RamAir95TA

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From: South Jersey

How do you know the car is getting too much fuel? What are your fueling mods? Injector sizing? Tuning? Lack of details won't make it any easier for us to figure it out.

Jan 25, 2012 | 12:28 AM

LigHtEmUp01

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the car randomly started to not wanna start and run like ****. i popped the first two injectors on it and cranked it over and it was dumping fuel like i was takin a ****. and it fouled out a set of plugs put new plugs in and started barely. the car was tuned a year ago everything in the fuel system is stock.

Jan 25, 2012 | 12:39 AM

LigHtEmUp01

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also no codes have come up and it ran good then got worse and worse and then it would not start. i swapped plugs in it and it started but only when i had the throttle to the floor. im pretty sure my maf and o2s are functioning correctly. once it runs i can see the fumes and smell gas from the pipes and it just has no get up but it doesnt miss. i am going to hook check the fuel pressure tomorrow.

Jan 25, 2012 | 02:42 PM

ahritchie

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From: Charlotte NC

Quote:

Originally Posted by LigHtEmUp01

my car is getting way to much fuel and is fouling plugs causing rough start. what could cause this?

Lots of stuff....I had similar issues that were caused by a combination of a bad coolant temp sensor (tells PCM it's ALWAYS -40 degrees outside and PCM dumps fuel) and leaky headers causing bad O2 readings.....which also makes the PCM dump gas like crazy. So, check coolant temp sensor, O2 sensors could be bad, MAF can also cause this, and potential exhaust leaks also need to be investigated. Possibly fuel pressure regulator? What mods have you done to it?

Jan 25, 2012 | 05:34 PM

LigHtEmUp01

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its in my sig and i know i dont have any exhaust leaks and both temp sending units are brand new.

Jan 26, 2012 | 01:01 AM

Big Al

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Quote:

Originally Posted by LigHtEmUp01

its in my sig and i know i dont have any exhaust leaks and both temp sending units are brand new.

Brand new sensors means nothing. Scan the PCM and see what temperatures its seeing. You could have a broken wire or bad connection. The sensor in the water pump is all you need to check, the one in the head is only for the dash gauge. And check the fuel pressure. If you don't have a scanner many parts stores will rent you one. Same for the fuel pressure tester. You actually buy it and they let you return it after using it. You can also check the injector pulse timing while your at it. The fuel pressure test port looks like a AC fitting on the fuel rail. Should have around 43 PSI with the engine off and it should go down a bit when you start it. If the pressure leaks down quick it's a sign of a leaky injector, bad regulator or bad fuel pump. I wouldn't worry about that unless it's fouling one or two cylinders. If they are all black it's not an injector problem.

Post what you find.

Worked on tuned port 350 yesterday that had 110 PSI on the rail. The regulator's pin was bent over. Don't ask me how, but that's what I found. It was running rich and somehow showed no codes??

Al 95 Z28

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