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Topic: Update new entire fuel system still have issues (Read 1785 times) previous topic - next topic

Update new entire fuel system still have issues

So new fuel tank, low pressure pump, high pressure pump and filter. Car runs awesome. Come to a light and every stop the car coughs shutters dies. Fires right back up. Idles good. No vacuum to the throttle kicker. Not sure if it's for the AC only? Only thing else I've done was run E3 spark plugs? Maybe that's a issue? Does have a rough idle back fires while reving. Doesn't like coasting either blah...blah....blah studders at 200 rpm battery light stalls. Fires up idles at 1000. I dunno too much plug not enough Coil?

Thinking next step is to replace the plugs

Re: Update new entire fuel system still have issues

Reply #1 –
I always run Motorcraft plugs in fords and Delco plugs in GM.  Has always treated me good.
Mike

Re: Update new entire fuel system still have issues

Reply #2 –
Run Motorcraft plugs and dump those pieces of shiznit in the trash can.  Buddy ran them once on his old Fox Mustang and it ran like a turd.  Put new Motorcraft plugs back in it and it ran like it should.  Had several other guys say the same thing.  Not sayin that is the issue but they do not seem to perform to well on our cars.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Re: Update new entire fuel system still have issues

Reply #3 –
Quote from: Knocker – on
. No vacuum to the throttle kicker. Not sure if it's for the AC only?
Do you have vacuum with the A/C on? If not this may be part of your problem.
On the 3.8L CFI V6 they use a motor operated positioner instead of the vacuum operated kicker.
On the 3.8 they use the positioner as a damper to keep the throttle from instantly  snapping all the way back to the curb idle position. It eases it back the last  quarter of an inch.

Re: Update new entire fuel system still have issues

Reply #4 –
Personally, I would throw those E3's in the trash. I've seen a lot of people across various platforms complain about how the car picked up a miss and stumble after putting the E3's in. These cars don't care for any fancy spark plugs. I've had my best luck with Motorcraft coppers and NGK coppers.
It's Gumby's fault.

Re: Update new entire fuel system still have issues

Reply #5 –
Well found arcing in the distributor cap. Changed it and the rotor. The slight miss vanished. However was still stalling with a 56% chance the battery wasn’t drained. Totally gave up. Noticed I have pretty good blow bye. Figured compression is down and I had a dead or weak hole. Checked my EGR by revving. Moved 1/2 inch. Shoved a screwdriver in felt a pop. Now the car runs absolutely perfect! Gets right up to highway speeds barely touching the gas. Battery has been staying charged. Runs like new........... :dunno:      Anyone have the scientific conclusion. What does the egr have to do with charging? Unless 600 rpm isn’t making charge and 800 does. Did have a VERY low idle
 

Re: Update new entire fuel system still have issues

Reply #6 –
What you've done is called purging the EGR.  Over time, carbon builds up in and around the pintle of the valve, more-so if there's been any kind of long standing running problem.  Back when I was a Ford dealership tech, we had to do this a lot on early 4.6 cars like Crown Vics. 
The first thing you need to know about EGR from a drivability standpoint, is that the recirculated exhaust gas is inert.  It takes the place of air that would oxidize the fuel and allow it to burn.  This has the effect of cooling the exhaust and leaning it out a little, and gives the cats some breathing room to work better.  As you've learned, a continuous leak of EGR into the intake causes aggressive drivability issues, like lean idle, and with idle control issues, come ineffective dashpotting.  You end up with low idle (below minimum RPM for charging), and an inability for the engine to recover to idle from running at speed, and what you did when manually opening the valve while the engine was running, was to allow the valve to open far enough (more than it usually would) that chips of carbon holding it open were blown clear. 

It sounds like you may have found and sorted out the drivability issues that caused this excess buildup in the first place, so you probably won't have this problem again.