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Car has terrible idle, boggy, and bad throttle response. (VIDEO INSIDE!)

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Old 02-24-2013, 11:19 PM   #1
lavertue
 
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Default Car has terrible idle, boggy, and bad throttle response. (VIDEO INSIDE!)

Titles says it all, car has bad idle, boggy acceleration, and stalls out when I slow down fast. Also has terrible throttle response. Checked iac and it was working. Checked alternator and battery, they were good. Vacuum lines are all good. Fpr is good. I'm not sure what else to check. It has been running bad like this for a little while now. I just installed my new Walbro 255lph fuel pump and thats when it started doing this "surging" type deal. If anyone has any ideas on what to check, please let me know. Thanks again, LaVertue.


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Old 02-25-2013, 08:22 AM   #2
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first thing I would check would be the check engine light, to see what codes you have
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Old 02-25-2013, 08:54 AM   #3
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check codes, check for vaccum leaks next and make sure there is no fuel pressure bleed down
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Old 02-25-2013, 01:41 PM   #4
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Did you disturb or otherwise mess with the orange cap on the end of the return line when you installed the pump?
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Old 02-26-2013, 07:14 PM   #5
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How do I check the computer? I don't believe you can get it checked at Advanced Auto correct? And Mattdel, I did not mess with it. Thanks for the help guys!
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Old 02-26-2013, 07:47 PM   #6
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Yes, you can check your codes at most auto parts shops. Do you have fuel pressure in your fuel rails? That can help check all the different problems that can bedevil your fuel supply. I don't know if they loan them, but I bought a cheap one 5 years ago and it has saved HOURS of chasing possible fuel supply problems.
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Old 02-26-2013, 09:59 PM   #7
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Yes, you can check your codes at most auto parts shops.
maybe obd 2 equipped cars, but there isn't a vatozone I've ever goNE TO THAT KNOWS WHAT A KOEO/KOER test is for a ford much less has a scanner to run one. Heck you're lucky if they can even find the plug under the hood.
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Old 02-26-2013, 10:03 PM   #8
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maybe obd 2 equipped cars, but there isn't a vatozone I've ever goNE TO THAT KNOWS WHAT A KOEO/KOER test is for a ford much less has a scanner to run one. Heck you're lucky if they can even find the plug under the hood.
Yeah, I've realized that the people who work at auto parts stores don't know a thing about cars, very annoying. However, I tried to run the test myself with the paper clip and the plug under the hood, I couldn't get my car to flash the codes. Any ideas?
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Old 02-27-2013, 12:01 AM   #9
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I'm not sure if this is it, but I may be a complete idiot. I ruled out the one thing it may be without even testing it, the TPS Sensor. So I headed to the garage and popped the hood, and gave it a go. Well, I'm not even getting any reading on my meter. So, I figured maybe I wasn't getting power to it at all, but I pulled the plug out and tested the power supply and I'm getting power, just the sensor isn't registering that I'm getting anything when i test it that way. So I guess that means it must be bad I'm assuming? I'm going to go tomorrow and get a new one and see if that resolves the issue. I'll keep you posted.
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Old 02-27-2013, 06:50 AM   #10
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^^^^make sure when backprobing it: 1. your tapped into the correct wires and 2. your probes are making contact
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Old 02-27-2013, 09:44 AM   #11
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Hmmm, stumped again. My meter wasn't getting juice last night, but my tps is good. Any other ideas on what to check? I still haven't figured out how to read my codes.
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Old 02-27-2013, 06:22 PM   #12
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Does the oil pressure switch have a fuel cut off ?
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Old 02-27-2013, 07:13 PM   #13
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Nope.
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Old 02-27-2013, 10:55 PM   #14
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I still can't figure out this check engine light thing. Anyone in the Tampa, Florida Area? Haha.
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Old 02-28-2013, 03:07 PM   #15
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Since the problem started right after installing your new fuel pump, that seems the logical place to start. New components don't always work right. Electric connections don't always hook up properly. Anything you touched in the process might have been mis-installed, or dirt, bits of gaskets, etc. may have been dislodged. Dirt in the tank may be blocking fuel pickup.

To avoid checking everything in the fuel system, I check the fuel pressure at the fuel pressure relief valve as that pressure will only be correct if everything upstream is working.

To conduct the test:
Disconnect power, Remove the fuel pressure relief valve cap and attach a fuel pressure test gauge. Attach power and crank the engine. Look for 30 to 45 pounds per square inch. Pressure that's too high can indicate that the pressure regulator is malfunctioning. Pressure that's too low indicates fuel filter, fuel pump or clogging problems


I hope this is helpful
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1999 V6.. Manual, CAI, High Performance Cats, High Flow single exhaust, Tune.

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Old 03-02-2013, 09:57 AM   #16
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Quote:
Originally Posted by rbowmar View Post
Since the problem started right after installing your new fuel pump, that seems the logical place to start. New components don't always work right. Electric connections don't always hook up properly. Anything you touched in the process might have been mis-installed, or dirt, bits of gaskets, etc. may have been dislodged. Dirt in the tank may be blocking fuel pickup.

To avoid checking everything in the fuel system, I check the fuel pressure at the fuel pressure relief valve as that pressure will only be correct if everything upstream is working.

To conduct the test:
Disconnect power, Remove the fuel pressure relief valve cap and attach a fuel pressure test gauge. Attach power and crank the engine. Look for 30 to 45 pounds per square inch. Pressure that's too high can indicate that the pressure regulator is malfunctioning. Pressure that's too low indicates fuel filter, fuel pump or clogging problems


I hope this is helpful
I will give this a try, I need to locate a gauge that I can borrow, but I will find one and test it out, and let you guys know the results.
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Old 03-02-2013, 02:36 PM   #17
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this sounds very similar to the problem the engine in my factory five roadster is currently exhibiting. i ran it out of gas a couple of weeks back and she's not real happy with me right now. new fuel filter, plugs, cleaned iac and throttle body, can of seafoam in the tank. seemed to solve the problem until i was driving it yesterday. terrible idle. sputters something awful under load. blowing black smoke. anyway, fwiw, my local oreilly auto parts store will "rent" the fuel pressure gauge set up. they put a charge on your credit card they then reverse when you bring it back.
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Old 03-02-2013, 02:36 PM
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