stator (hall effect sensor) or tfi?

[BlackVert]

Please help me diagnose this:

Car sometimes cranks up to 15 seconds before starting.

Runs fine until warmed up.

Once warmed up, hesitates and stumbles upon acceleration. Seems to get worse the longer the car runs.

The more i read, the more it sounds like the stator or TFI is going bad, but the car has not died on me out of the blue (at least not yet) like other people have described when their stator has gone bad.

Which problem (or both) happen only once the car is warmed up?

I have checked and replaced (or found to be good):

Fuel pressure regulator
Distributor cap/rotor
fuel pump
mass air meter

 

[BlackVert]

ttt

 

[helix007]

have you replaced the fuel filter?

 

[BlackVert]

have you replaced the fuel filter?

yep, just last week

 

[crazypete]

Clogged catalytic converters will do the same thing. Unbolt your header flanges and run the car again (I am assuming it does this at idle warmed up as well). I would not recommend driving like this since it will be loud. If this cures it, your cats are clogged (if you still have them). If not, it is the TFI.

 

[93 teal terror]

Take your TFI module and have it tested at your local autoparts store. If its bad get a new one, but I wouldnt get one from advance. I had 3 bad modules from there that made the car run worse than before. If you going to buy a new one get a ford unit or one from a quality aftermarket company. Good Luck.

 

[tmoss]

TFI failures are heat related. I'd start there first. If it runs the same, keep the TFI as a spare - I always have one in the trunk with the tool for removing/installing it.

 

[88-GT]

Hey it kinda sounds like what my car was doing...well...before like 5 mins ago. I just finished changing mine and a what a difference. But on the other hand mine ALWAYS died just sitting there idling. Take it to your autoparts store and get it tested, and make sure they go thru at least 10 tests to get it nice and warmed up. Mine failed on the 2nd test. Good luck.

 

[trbkrb]

Could be the TFI or the stator. Mine was acting very similar, missing once warmed up, and it progresively got worse. Changed the TFI under warranty but no difference. Then i cooled the distributor base with slow running water from a hose and the missing stopped until it warmed up again. Did this twice more with the same results. I then swapped in a loaner distributor from a friend, and it ran fine. Ended up the stator had a crack or something where it mounts to the distributor and it would not get the right signal when warm. Eventually it broke loose and would hit the distributor shaft while it was turned. If you can get a good distributor to borrow for a test, try that if the TFI test does not come back bad.

Good luck!

 

[BlackVert]

11/11 update: hall effect sensor replaced today ... it did not fix it.

I am going to log the ECT and also replace the FPR with an AFPR.

it should read 39psi with the vacuum off and plugged, right? i don't think i plugged the vacuum tube the last time i read it ...

 

[JB66]

did you have the codes read while you were at the parts store?

 

[BlackVert]

did you have the codes read while you were at the parts store?

i haven't gotten a check engine light in months. doesn't that mean there shouldn't be any codes to read?

 

[JB66]

Bad sensors and electronic components don't always throw the light on if they are within design parameters. ie. An ECT sensor failure will not turn the light on sometimes if it's still feeding the ECM information, even though that information may be incorrect.