engine starts but stalls help pls

[danism]

it is obd2 acording to ford, i no the port is not a dummy, because all other tests i do use that port (koer) still gives trouble codes

 

[panamexplorer]

If your Explorer turns over and 'trys' to start but won't idle and you have to depress the accelerator down and high rev it or two foot brake and gas it to keep it going, then I can tell you that with my 98 4.0 XLT it was the IAC. In that condition you can't clean it you have to replace it. If it starts idles rough and stalls it is more likely to be MAF or vacuum/gasket related. MAF can also give you engine ping or CAT codes due to a 'too rich' mixture. Other than that the TPS can also affect idle, but more of a high/low surge problem.
Food for thought.

 

[danism]

changed iac and tps had it run for a couple min got codes po 1000, and 603(pcm keep alive memory error)

 

[2000StreetRod]

keep alive power

The power to the PCM for the keep alive memory comes from fuse 4 (20 amps) in the power distribution box. It should have power at all times.

 

[danism]

would this be whats causing my trouble?

 

[panamexplorer]

Check for loose connections or corrosion around the power distribution box. You may have a short, bad ground or bad fuse. I had a parts Explorer that had a couple of wires in the harness behind broken.

 

[danism]

fuse is good, no sign of broken or loose wirring, no power to the tps

 

[96eb96]

changed iac and tps had it run for a couple min got codes po 1000, and 603(pcm keep alive memory error)

PCMs go bad too...not unheard of.

 

[danism]

any way to be sure?

 

[danism]

well damage be visable if it is bad

 

[danism]

wouldnt that make it impossible to run at all?

 

[2000StreetRod]

Reference voltage

fuse is good, no sign of broken or loose wirring, no power to the tps

The PCM supplied reference voltage to the TPS also supplies the DPFE and the pressure transducer in the fuel tank. Does your fuel gauge show a reading on the instrument panel?

Are you sure that you're reading the voltage between the brown/white wire (+) and the gray/red (-) wire at the TPS connector? If so, move the negative probe to ground to see if you get a reading. If you get a reading to ground then you have a problem with your sensor common return wires to the PCM. Check the main engine harness connector that is held together with a bolt.

 

[danism]

installed new pcm today and it runs great exept it is still hard to start while cold(fires rite up when warm)i have to feather the gas for the first min or two(i only have a lean code now) any ideas?

 

[2000StreetRod]

What codes?

Did you clear the old codes after replacing the PCM? What are the current codes?

So far you've replaced the fuel filter and the MAF sensor. If you're getting lean codes for both banks then add a bottle of fuel injector cleaner to your fuel tank, perform the TPS Test Procedure, the Fuel pressure test procedure and start checking for vacuum leaks.

 

[danism]

broken down again.....after having it pluged in all night it started(still had to restart it about 6 times and feather the gas for about a minute). i also had battery disconected all nite. i kept it running for about 2 hours, shut it off to go into the store for about 20 minutes, tried to start it again and it wouldnt go, my syliniod crapped out while iwas tryin to start it, so i had to cross it with a screwdriver. i replaced the sylinoid and now i think i cooked my starter tryin to start it. i have found no vacum leaks, i have fuel pressure, compression, and spark, its like i dont have a choke!!!

 

[danism]

I miss the carberated days

 

[panamexplorer]

This may be a silly question but are you replacing parts from the wreckers or new?
Because it still sounds like the IAC module.
The one you replaced could be a dud. Used or new it not the first time a part you think you have is replaced okay is still your problem.

 

[danism]

any other ideas? i have tried another iac(from wrecking yard) and still the same thing. i am at the point were i am tempted to put a carberated small block in it(probably wouldnt have spent any more cash than i have already lol)

 

[2000StreetRod]

fuel pressure?

Any chance of water or condensation in the fuel tank? Have you added fuel injector cleaner to the fuel tank and tested your fuel pressure?

 

[danism]

i seem to have fuel pressure, my problems seemed to get worse after fueling up i guess it could be bad gas. i added injector cleaner, didnt seem to help. i was starting to think maybe a fuel pump, never realy thought about bad gas. do these tanks have drain plugs?