Hey whats up? First time poster.

Recently ive been having an idle problem. Sometimes it will idle rough at startup while other times its fine. Sometimes it will idle rough at a stop light and sometimes it idles fine. The air filter, fuel filter, cap, rotor, plugs, and wires are all new. Ive cleaned the IAC. The battery and alternator tested good. Out of curiousity i disconnected/plugged the vac line at the EGR and everything seemed to be ok until a few miles of driving it acted up again so i can only guess the EGR is ok as having it plugged didnt effect anything.

I checked all vac lines only to find one crack but replaced it. Still having problems. Engine stalled twice sitting at idle but started right up no problem.

Right now im questioning the MAF, TPS, fuel pump relay or the fuel pump itself and the sock filter.

Along with a rough low idle, ive also experienced some 'bucking' as well some hesitation when i start to accelerate but this isnt always a problem.

I can take care of the MAF, TPS, and the fuel pump issues if i have to, just looking for opinions first before i go after the fuel pump.

Its a practically stock AOD 93 GT with about 130k on it.

Thanx.

 

Sounds like what is happening to mine (87 GT with 134K miles)

I was going to suggest to replace the wires and plugs (which I need to do on mine).

Swirl

 

I have some of the same symtoms but not at idil my car idils great but bucks some times while giving it the gas. i checked TPS and cleaned IAC, MAF, and TB. runs a little better. hopfully it was just dirty who knows

 

try cleaning your maf with some electronic parts cleaner... remove it from the car, spray it out, and let it dry... very well

then pop it back in and try it out.... they do get dirty after a while

 

Thanks for the responses.

I still have the vac hose from the EGR plugged. The idle is still a bit rough at times but not as often so maybe im on the right track as i havent experienced any bucking since plugging it. Coincidence? Ill try cleaning the MAF anyway and i still need to check the TPS. Will it hurt to keep driving with the EGR plugged like ive done? I also cleaned the PCV filter element which hasnt been touched since 21k. Half a can of carb cleaner took care of that , no joke. The valve itself is new.

Ok, checked for codes using the MIL, got a code 95 for sure (got it on both KOEO and KOER). I thought i saw a 14 as well but im not sure.

14 - PIP circuit failure
95 - secondary fuel pump circuit failure - ECA to ground

I know where the ECA is but where is the ground that 95 pertains to? Still no codes while im driving.

On the way home my headlights started to dim a little at a stop light and at the same time my idle got rough. Great, another problem. I get home and the idle is fine as are the headlights. All i had on were the headlights, no foglights.

Its always something.

 

My car has been doing the rough idle and dimming headlight thing the past few days. I know its not my alternator because most of the time its fine and I put on a 130 amp alternator.
Sometimes my check engine light comes on and I scanned it and got a TPS code. I think Im just going to replace the TPS and see if that helps.

 

The TPS will cause all of those problems. Messing with mine now, a new one, and it will cause all kinds of problems if not properly set. Do you have a fast idle when cold?

 

My idle is fine at startup. The past few days with the EGR plugged everything seemed to a little better but after a few miles it would idle rough when i stopped, but not everytime.

Just today i checked my TPS and it read a .587. I remember setting it at a .98 something a while back. So, i reset it to .998, tightened it up and it still read a .986. The idle sounded a little off but it wasnt rough. I also noticed very small splits in the plastic housing at one of the screws. I drove maybe a mile to the bank and the car bucked once slightly. I checked the TPS when i got back and got a 1.007. Im not to sure about the fast idle bit, how fast is considered fast? Before i reset the TPS it was closer to 900-1000. After resetting it it went down to 600-700 id say.

Regardless, ill be buying a new TPS. As for the MAF and TB, they still need cleaned but nobody seems to have a security 20 torx bit to remove the sensor.

Ill get back to you, everybodys been great, thanx.

 

It could be the sticky egr but when i worked at ford we had a lot of idle problems with our type of iac's so ford has a plate that you can put between the iac and throttle body, it bypasses the iac a little bit with allen screw adjustments. You can go to your local ford dealer and buy this kit.

 

try sea foam