runs rough back fires, smells rich, stalls

wayneo856

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Aug 18, 2020
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2000 mustnag 3.8 v6 pos hard to explain start up idles great no problem you can drive it around the block and then it will lose power back fire, smell rich, run rough miss fire and have no throttle response,u hit the gas and the tach wont read and it just boggs out ( it acts like a carburetor car thats out of gas ) turn it off set for a minute and then it will run fine for like 3 minutes. and start acting up again..and the longer you drive it the worse it gets till after you stop and sit start it up put in gear it stalls...cost me 75 bucks 2 weeks ago to get towed home one mile.......i've bout had it...brand new fuel tank, new pump new filter .spark plugs and wires... the old tank was full of rust could this have damaged the injectors?? a guy come to look at it said it acts like it the trans going into overdrive mode his ranger is doing the same thing... this dont have an OD
 
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08GT500

Active Member
Jul 12, 2018
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2000 mustnag 3.8 v6 pos hard to explain start up idles great no problem you can drive it around the block and then it will lose power back fire, smell rich, run rough miss fire and have no throttle response,u hit the gas and the tach wont read and it just boggs out ( it acts like a carburetor car thats out of gas ) turn it off set for a minute and then it will run fine for like 3 minutes. and start acting up again..and the longer you drive it the worse it gets till after you stop and sit start it up put in gear it stalls...cost me 75 bucks 2 weeks ago to get towed home one mile.......i've bout had it...brand new fuel tank, new pump new filter .spark plugs and wires... the old tank was full of rust could this have damaged the injectors?? a guy come to look at it said it acts like it the trans going into overdrive mode his ranger is doing the same thing... this dont have an OD
Hi,
Sorry to hear. Have a Scantool to pull the Computer trouble codes? Check engine light illuminated when the car is running? I’m being a bit vague here listing the common issues that you can check/test that cost little to nothing.
The most helpful tool is Computer codes, really narrows things down. Check off the other items on the list, see if you find anything, but pull the Codes and post them. They may still be present in the absence of a check engine light. Beyond that, it just becomes speculation....
A Little history...
Was this same problem occurring when you replaced the Tank, Pump, Filter, Wires, Plugs, and continued after it was all replaced, or was it not starting at all, or have a completely different problem before this? If different, what occurred..?
Media in the injectors is unlikely if you had a Filter on the fuel line, although possible, the Trouble codes will help diagnose the problem, more than likely it would likely have no power at any point now, even when it first starts & drives, seems normal until a few minutes after it runs-correct?.
Will the engine stay running if it’s just idling in the driveway in Park? Let it warm up..does it stall out, or continue running?

This May/May not be related....a bit ironic..
Your 2000 3.8l V-6 A/T Does have Overdrive, electronically enabled, there’s a smalller button on the shifter that enables/disables it. Press the button on the shifter to disable it, light on the dash turns on.
Trans fluid will generally smell burnt if you have a Band hanging up, Fwd clutch issue. After the car warms up, pull the Trans.dipstick..
1) Level low?
Wipe it with a white rag...
2) Any pieces from the oil on the rag?
3) Oil have a burnt odor?
Could take it for a short ride up the street next to home after disabling Overdrive, but it will show up in the Codes. Your call.
Post what you find...
Don’t spend any $$ on parts until you’ve proven via testing it isn’t functioning as intended. Also confuses locating the real issue.
~~~> Buy a 20-25$ Shop manual (Haynes or a Chilton) for your Car, most part stores carry them..

1) Check for trouble codes with a Scantool yet? Most stores will rent you one (or let you borrow it). Post the Codes.
2) Check your Alternator output with the Car running with a Voltmeter, should have 13.7-13.9 Volts output, car running. Check your Battery with the Car sitting, should have 12VDC minimum.
3) Fuel pressure at the fuel rail should be 36-38lbs, pull the fuel pressure regulator’s rubber line off, pull a little vacuum on it orally, taste any fuel? Fuel pressure should be 40lbs with the line removed. Check that your connections are solid to the pump, also check the inertia switch in the trunk for solid connections.
4) When the car stalls does the fuel pump cease to run before it stalls, and when you try starting the car just after it stalls,(when you have to wait a few minutes before it starts again) do you hear the fuel pump run for 4-6 seconds to prime the fuel injectors when you turn the key to the run position, and when you’re cranking the motor over, attempting to start it?
5) Pull and clean the Air Filter, or replace and clean out any dirt inside the Filterbox with a vacuum cleaner.
6) Get a can of CRC MAF cleaner and spray the MAF sensor a few times, don’t touch it, just spray it good. Take a look around the engine compartment for any melted or detached/loose rubber vacuum lines.
7) Ground wires on these cars cause issues with these Cars if they become loose, dirty or corroded. Check and Clean the terminals on the battery, check the ground wire strap on the back of the block, make certain they are tight and not corroded.
See what you find and ask the gentleman that came over if he can pull the engine codes for you with his Scantool.
Good luck!
-John
 
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08GT500

Active Member
Jul 12, 2018
898
139
53
50
Massachusetts
thanks John
Hi Wayne,
How’d you make out with your 2000 Mustang? Were you able to get your OD all right, any part of your issues?
At any rate the 0.68:1 OD ratio vs 1:1 will improve your fuel economy.
Didn’t mean to alarm with ScanTools & codes if new to you, if I did. It’s quite priceless for locating issues/diagnostics.
Missing a 50$ Scantool in your toolbox now is like not having a socket set in the 70’s.
You’ll learn it within an hour, you cannot hurt anything, shows all live engine data, it’s not expensive & can be used on all typical OBD-2 Cars. May need an adapter for your Lamborghini, but you’re ok otherwise, lol.
If you need more info, please post it, happy to help!
best!
John