99 mercury villager runabilty problem help

[stumppper]

we have a 1999 mercury villager 3.3 motor
this is what it does and how it acts, when you first start it it starts fine, but give it some gas and it starts to pop and miss and act up (acts like timing is retarded or advanced) pops spits etc the more gas i give it the worse it gets ,,now after it runs for 2-3 minutes, it runs fine accelerates great no miss no pop nothing , rpm all works fine. it has been at sveral shops and i think they are over loking something. new plugs .cap rotor, injectors , map and maf sensor. computer changed as well
has anyone ever ran into this , no codes nothing, all seems fine when you look at it on a lave data stream help help runaround [email protected]

[IH8SPM]

Have you had the cat. converter checked. You seem to have a clog in the exhaust that once warm allows air to flow. Is this problem only on certain days(rain,very hot, etc). You may need to check your ignition for a worn gasket which allows moiture to enter and sometimes cause this on some vehicles. Please post back this is a very intresting problem.

[stumppper]

Originally Posted by IH8SPM

Have you had the cat. converter checked. You seem to have a clog in the exhaust that once warm allows air to flow. Is this problem only on certain days(rain,very hot, etc). You may need to check your ignition for a worn gasket which allows moiture to enter and sometimes cause this on some vehicles. Please post back this is a very intresting problem.

we have checked the cat its seems fine with good flow, the ign and dist seem ok as well and it does it everytime its cold, as in not started for a few hours.. not cold as in temp outside,

[IH8SPM]

Have you checked the battery. Your battery may be losing power from age or a the common problem a bad starter soleniod. Either way it sounds as if you have moisture that is building in current carrying location. You may want to retest all those item such as the cables and distributer. In my experience they some times break internally. If you have checked or replaced all that already then I am going to have to look deeper into your problem. Send or post me a list of things changed and a step by step of how it happens. Start in the morinig but first check the battery voltage.

[drcoffee]

Have you checked the IAC valve? It controls the air flow at idle on cold starts. The fact that it only effets it while cold must be related to the "choke" function. You have changed the computer, so what's left? EGR, IAC, sticky throttle plate, bad battery ground wire, vacuum leak (intake gasket). Also check the coolant temp sensor to the computer.

[IH8SPM]

I did not mention the IAC valve because he has a 99 not a 93-98 where that problem is very common. I re read your post several time and the misfire sounds like a fuel problem. Check the fuel system, you may have a bad filter or pump then this would explain the pop which also happens when the engine and and injectors are robbed of fuel. I am not to familiar with your year because they do not suffer as much. Ford did a better job with your year.

[drcoffee]

Originally Posted by IH8SPM

I did not mention the IAC valve because he has a 99 not a 93-98 where that problem is very common. I re read your post several time and the misfire sounds like a fuel problem. Check the fuel system, you may have a bad filter or pump then this would explain the pop which also happens when the engine and and injectors are robbed of fuel. I am not to familiar with your year because they do not suffer as much. Ford did a better job with your year.

What's curious is that it runs fine when at operating temp when a weak fuel pump has the most stress.

The computer is not sensing something correctly while in choke mode. There's usually more than one temp sensor, one for the dash and another one or two for the computer. ie air intake temp, coolant temp, tranny, etc. Anything else would also affect it while hot and running.

Keep us posted once you find it.

Thanks.